1105 lines
164 KiB
XML
1105 lines
164 KiB
XML
<document ID-DOI="10.1038/s41598-017-02161-w" ID-GBIF-Dataset="3071d3d1-dc4a-4ae5-813c-67b6774ee74b" ID-PMC="PMC5435714" ID-PubMed="28515439" ID-Zenodo-Dep="3748931" approvalRequired="1" approvalRequired_for_illustrations="1" checkinTime="1586683904713" checkinUser="jeremy" docAuthor="Paul M. Gignac & Gregory M. Erickson" docDate="2017" docId="03F687FB0559D612FE77FBC32F77FA2E" docLanguage="en" docName="GignacErickson2017Osteophagy.pdf.imf" docOrigin="Scientific Reports 7" docStyle="DocumentStyle{}" docTitle="Tyrannosaurus rex Osborn 1905" docType="treatment" docVersion="9" lastPageNumber="8" masterDocId="FFCFFF83055BD615FFE8FFB72B53FFD4" masterDocTitle="The Biomechanics Behind Extreme Osteophagy in Tyrannosaurus rex" masterLastPageNumber="2012" masterPageNumber="2012" pageNumber="3" updateTime="1668129582143" updateUser="ExternalLinkService">
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<mods:mods xmlns:mods="http://www.loc.gov/mods/v3">
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<mods:titleInfo>
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||
<mods:title>The Biomechanics Behind Extreme Osteophagy in Tyrannosaurus rex</mods:title>
|
||
</mods:titleInfo>
|
||
<mods:name type="personal">
|
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<mods:role>
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<mods:roleTerm>Author</mods:roleTerm>
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||
</mods:role>
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||
<mods:namePart>Paul M. Gignac</mods:namePart>
|
||
<mods:affiliation>Department of Anatomy and Cell Biology, Oklahoma State University Center for Health Sciences, Tulsa, Oklahoma, 74107 - 1898, USA.</mods:affiliation>
|
||
<mods:nameIdentifier type="email">paul.gignac@okstate.edu</mods:nameIdentifier>
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</mods:name>
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<mods:name type="personal">
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<mods:role>
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<mods:roleTerm>Author</mods:roleTerm>
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||
</mods:role>
|
||
<mods:namePart>Gregory M. Erickson</mods:namePart>
|
||
<mods:affiliation>Department of Biological Science, Florida State University, Tallahassee, Florida, 32306 - 4295, USA</mods:affiliation>
|
||
</mods:name>
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<mods:typeOfResource>text</mods:typeOfResource>
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<mods:relatedItem type="host">
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<mods:titleInfo>
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<mods:title>Scientific Reports</mods:title>
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||
</mods:titleInfo>
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||
<mods:part>
|
||
<mods:date>2017</mods:date>
|
||
<mods:detail type="pubDate">
|
||
<mods:number>2017-05-17</mods:number>
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||
</mods:detail>
|
||
<mods:detail type="volume">
|
||
<mods:number>7</mods:number>
|
||
</mods:detail>
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||
<mods:extent unit="page">
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||
<mods:start>2012</mods:start>
|
||
<mods:end>2012</mods:end>
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||
</mods:extent>
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||
</mods:part>
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</mods:relatedItem>
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<mods:classification>journal article</mods:classification>
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<mods:identifier type="DOI">10.1038/s41598-017-02161-w</mods:identifier>
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<mods:identifier type="GBIF-Dataset">3071d3d1-dc4a-4ae5-813c-67b6774ee74b</mods:identifier>
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<mods:identifier type="PMC">PMC5435714</mods:identifier>
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<mods:identifier type="PubMed">28515439</mods:identifier>
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<mods:identifier type="Zenodo-Dep">3748931</mods:identifier>
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</mods:mods>
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<treatment ID-DOI="http://doi.org/10.5281/zenodo.3808819" ID-GBIF-Taxon="163636824" ID-Zenodo-Dep="3808819" LSID="urn:lsid:plazi:treatment:03F687FB0559D612FE77FBC32F77FA2E" httpUri="http://treatment.plazi.org/id/03F687FB0559D612FE77FBC32F77FA2E" lastPageId="7" lastPageNumber="8" pageId="2" pageNumber="3">
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<subSubSection box="[415,507,1140,1166]" pageId="2" pageNumber="3" type="description">
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||
<paragraph blockId="2.[415,1480,1140,1913]" box="[415,507,1140,1166]" pageId="2" pageNumber="3">
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<heading bold="true" box="[415,507,1140,1166]" fontSize="11" level="1" pageId="2" pageNumber="3" reason="0">
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||
<emphasis bold="true" box="[415,507,1140,1166]" pageId="2" pageNumber="3">Results</emphasis>
|
||
</heading>
|
||
</paragraph>
|
||
</subSubSection>
|
||
<subSubSection box="[415,711,1171,1193]" pageId="2" pageNumber="3" type="nomenclature">
|
||
<paragraph blockId="2.[415,1480,1140,1913]" box="[415,711,1171,1193]" pageId="2" pageNumber="3">
|
||
We found that adult
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[608,661,1172,1193]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="2" pageNumber="3" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[608,622,1172,1193]" italics="true" pageId="2" pageNumber="3">T</emphasis>
|
||
.
|
||
<emphasis box="[632,661,1172,1193]" italics="true" pageId="2" pageNumber="3">rex</emphasis>
|
||
</taxonomicName>
|
||
skull
|
||
</paragraph>
|
||
</subSubSection>
|
||
<subSubSection pageId="2" pageNumber="3" type="description">
|
||
<paragraph blockId="2.[415,1480,1140,1913]" pageId="2" pageNumber="3">
|
||
lengths in our sample range from 111.5 to 136.5 cm (
|
||
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||
and
|
||
<materialsCitation ID-GBIF-Occurrence="2598005741" box="[1345,1475,1171,1192]" collectionCode="LACM" pageId="2" pageNumber="3" specimenCode="LACM 23844">LACM 23844</materialsCitation>
|
||
, respectively) (
|
||
<tableCitation box="[551,623,1198,1220]" captionStart="Table 1" captionStartId="5.[415,469,401,422]" captionTargetBox="[423,903,134,368]" captionTargetId="graphics@5.[415,970,124,373]" captionTargetPageId="5" captionText="Table 1. Adult52 Tyrannosaurus rex specimens, head lengths (HL), head widths (HW), and bite forces (BF, in newtons [N]) estimated in this study (see Methods and Supplementary Table S2 for measurement details and forces at specific tooth positions; see main text for museum abbreviations)." httpUri="http://table.plazi.org/id/DF206665055ED610FE77FE262F37FE08" pageId="2" pageNumber="3" tableUuid="DF206665055ED610FE77FE262F37FE08">Table 1</tableCitation>
|
||
). Skull widths range from 59.2 to 90.2 cm (
|
||
<materialsCitation ID-GBIF-Occurrence="2598005750" box="[1042,1138,1198,1219]" collectionCode="BHI" pageId="2" pageNumber="3" specimenCode="BHI 4100">BHI 4100</materialsCitation>
|
||
and
|
||
<materialsCitation ID-GBIF-Occurrence="2598005754" box="[1186,1346,1198,1219]" collectionCode="FMNH" pageId="2" pageNumber="3" specimenCode="FMNH PR2081">FMNH PR 2081</materialsCitation>
|
||
, respectively) (
|
||
<tableCitation box="[421,489,1224,1246]" captionStart="Table 1" captionStartId="5.[415,469,401,422]" captionTargetBox="[423,903,134,368]" captionTargetId="graphics@5.[415,970,124,373]" captionTargetPageId="5" captionText="Table 1. Adult52 Tyrannosaurus rex specimens, head lengths (HL), head widths (HW), and bite forces (BF, in newtons [N]) estimated in this study (see Methods and Supplementary Table S2 for measurement details and forces at specific tooth positions; see main text for museum abbreviations)." httpUri="http://table.plazi.org/id/DF206665055ED610FE77FE262F37FE08" pageId="2" pageNumber="3" tableUuid="DF206665055ED610FE77FE262F37FE08">Table 1</tableCitation>
|
||
). (Notably,
|
||
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|
||
has been reported as the largest specimen for the taxon
|
||
<bibRefCitation author="Larson, P. L." box="[1267,1282,1221,1235]" editor="Rosenberg, G. & Wolberg, D." journalOrPublisher="Paleontological Society Special Publ." pageId="2" pageNumber="3" pagination="139 - 155" part="7" refId="ref8841" refString="37. Larson, P. L. Tyrannosaurus Sex in Dino Fest Proceedings, Paleontological Society Special Publ. 7 (eds Rosenberg, G. & Wolberg, D.) 139 - 155 (1994)." title="Tyrannosaurus Sex" type="proceedings paper" volumeTitle="Dino Fest" year="1994">
|
||
<superScript attach="left" box="[1267,1282,1221,1235]" fontSize="6" pageId="2" pageNumber="3">37</superScript>
|
||
</bibRefCitation>
|
||
; however, we instead found that
|
||
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|
||
has the longest and, marginally, the second widest skull). Based on the minimum reliable measurement of tooth contact areas (at 1 mm from the crown apex)
|
||
<bibRefCitation author="Erickson, G. M." box="[1067,1074,1274,1288]" journalOrPublisher="PLoS ONE" pageId="2" pageNumber="3" pagination="e 31781" part="7" refId="ref7358" refString="8. Erickson, G. M. et al. Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation. PLoS ONE 7, e 31781, doi: 10.1371 / journal. pone. 0031781 (2012)." title="Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation" type="journal article" year="2012">
|
||
<superScript attach="left" box="[1067,1074,1274,1288]" fontSize="6" pageId="2" pageNumber="3">8</superScript>
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||
</bibRefCitation>
|
||
and the deepest known
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[1309,1364,1278,1300]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="2" pageNumber="3" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1309,1323,1279,1300]" italics="true" pageId="2" pageNumber="3">T</emphasis>
|
||
.
|
||
<emphasis box="[1335,1364,1279,1300]" italics="true" pageId="2" pageNumber="3">rex</emphasis>
|
||
</taxonomicName>
|
||
tooth mark indentations (~37.5 mm)
|
||
<superScript attach="none" box="[660,698,1301,1315]" fontSize="6" pageId="2" pageNumber="3">
|
||
<bibRefCitation author="DePalma, R. A. II. & Burnham, D. A. & Martin, L. D. & Rothschild, B. M. & Larson, P. L." box="[660,675,1301,1315]" journalOrPublisher="Proc. Nat. Acad. Sci. USA" pageId="2" pageNumber="3" pagination="12560 - 12564" part="110" refId="ref7711" refString="15. DePalma, R. A. II., Burnham, D. A., Martin, L. D., Rothschild, B. M. & Larson, P. L. Physical evidence of predatory behavior in Tyrannosaurus rex. Proc. Nat. Acad. Sci. USA 110, 12560 - 12564, doi: 10.1073 / pnas. 1216534110 (2013)." title="Physical evidence of predatory behavior in Tyrannosaurus rex" type="journal article" year="2013">15</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Erickson, G. M. & Olson, K. H." box="[683,698,1301,1315]" journalOrPublisher="J. Vert. Paleo" pageId="2" pageNumber="3" pagination="175 - 178" part="16" refId="ref7843" refString="17. Erickson, G. M. & Olson, K. H. Bite marks attributable to Tyrannosaurus rex: preliminary description and implications. J. Vert. Paleo 16, 175 - 178, doi: 10.1080 / 02724634.1996.10011297 (1996)." title="Bite marks attributable to Tyrannosaurus rex: preliminary description and implications" type="journal article" year="1996">17</bibRefCitation>
|
||
</superScript>
|
||
, we determined that maxillary tooth contact areas range from 6.3 to 565.1 mm
|
||
<bibRefCitation author="Fosse, P." box="[1472,1479,1301,1315]" journalOrPublisher="J. Taphon" pageId="2" pageNumber="3" pagination="197 - 217" part="10" refId="ref7119" refString="2. Fosse, P. et al. Bone modification by modern wolf (Canis lupus): A taphonomic study from their natural feeding places. J. Taphon 10, 197 - 217 (2012)." title="Bone modification by modern wolf (Canis lupus): A taphonomic study from their natural feeding places" type="journal article" year="2012">
|
||
<superScript attach="left" box="[1472,1479,1301,1315]" fontSize="6" pageId="2" pageNumber="3">2</superScript>
|
||
</bibRefCitation>
|
||
(right M3 of
|
||
<materialsCitation ID-GBIF-Occurrence="2598005781" box="[542,637,1331,1352]" collectionCode="MOR" pageId="2" pageNumber="3" specimenCode="MOR 980">MOR 980</materialsCitation>
|
||
and left M4 of
|
||
<materialsCitation ID-GBIF-Occurrence="2598005742" box="[787,917,1331,1353]" collectionCode="RTMP" pageId="2" pageNumber="3" specimenCode="RTMP 81.6.1">RTMP 81.6.1</materialsCitation>
|
||
, respectively) at minimum and maximum crown heights, respectively (
|
||
<httpUri box="[540,772,1358,1380]" httpUri="https://static-content.springer.com/esm/art%3A10.1038%2Fs41598-017-02161-w/MediaObjects/41598_2017_2161_MOESM1_ESM.xls" pageId="2" pageNumber="3">Supplementary Table S2</httpUri>
|
||
). Estimated bite forces range from up to 8,526 to 17,769 N (1,917 to 3,995 lb) mesially (right P1 of
|
||
<materialsCitation ID-GBIF-Occurrence="2598005747" box="[645,737,1385,1406]" collectionCode="BHI" pageId="2" pageNumber="3" specimenCode="BHI 4100">BHI 4100</materialsCitation>
|
||
and right and left P1 of
|
||
<materialsCitation ID-GBIF-Occurrence="2598005749" box="[966,1123,1385,1406]" collectionCode="FMNH" pageId="2" pageNumber="3" specimenCode="FMNH PR2081">FMNH PR 2081</materialsCitation>
|
||
, respectively) and 18,014 N to 34,522 N (4,050 to 7,761 lb) distally (right M12 of
|
||
<materialsCitation ID-GBIF-Occurrence="2598005745" box="[828,920,1411,1433]" collectionCode="BHI" pageId="2" pageNumber="3" specimenCode="BHI 4100">BHI 4100</materialsCitation>
|
||
and right M12 of
|
||
<materialsCitation ID-GBIF-Occurrence="2598005753" box="[1094,1252,1411,1433]" collectionCode="FMNH" pageId="2" pageNumber="3" specimenCode="FMNH PR2081">FMNH PR 2081</materialsCitation>
|
||
, respectively) (
|
||
<tableCitation box="[1395,1466,1411,1433]" captionStart="Table 1" captionStartId="5.[415,469,401,422]" captionTargetBox="[423,903,134,368]" captionTargetId="graphics@5.[415,970,124,373]" captionTargetPageId="5" captionText="Table 1. Adult52 Tyrannosaurus rex specimens, head lengths (HL), head widths (HW), and bite forces (BF, in newtons [N]) estimated in this study (see Methods and Supplementary Table S2 for measurement details and forces at specific tooth positions; see main text for museum abbreviations)." httpUri="http://table.plazi.org/id/DF206665055ED610FE77FE262F37FE08" pageId="2" pageNumber="3" tableUuid="DF206665055ED610FE77FE262F37FE08">Table 1</tableCitation>
|
||
). These are among the highest bite forces estimated for any animal (16,414 N [3,690 lb] was directly measured for a bob-tailed, 4.51 m Australian saltwater crocodile [
|
||
<taxonomicName authorityName="Schneider" authorityYear="1801" box="[902,1081,1465,1486]" class="Reptilia" family="Crocodylidae" genus="Crocodylus" kingdom="Animalia" order="Crocodylia" pageId="2" pageNumber="3" phylum="Chordata" rank="species" species="porosus">
|
||
<emphasis box="[902,1081,1465,1486]" italics="true" pageId="2" pageNumber="3">Crocodylus porosus</emphasis>
|
||
</taxonomicName>
|
||
]
|
||
<superScript attach="none" box="[1089,1118,1461,1475]" fontSize="6" pageId="2" pageNumber="3">
|
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<bibRefCitation author="Erickson, G. M." box="[1089,1096,1461,1475]" journalOrPublisher="PLoS ONE" pageId="2" pageNumber="3" pagination="e 31781" part="7" refId="ref7358" refString="8. Erickson, G. M. et al. Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation. PLoS ONE 7, e 31781, doi: 10.1371 / journal. pone. 0031781 (2012)." title="Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation" type="journal article" year="2012">8</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Erickson, G. M. & Gignac, P. M. & Lappin, A. K. & Vliet, K. A. & Webb, G. J. W." box="[1103,1118,1461,1475]" journalOrPublisher="J. Zool." pageId="2" pageNumber="3" pagination="48 - 55" part="292" refId="ref8882" refString="38. Erickson, G. M., Gignac, P. M., Lappin, A. K., Vliet, K. A. & Webb, G. J. W. A comparative analysis of ontogenetic bite-force scaling among Crocodylia. J. Zool. 292, 48 - 55, doi: 10.1111 / jzo. 12081 (2014)." title="A comparative analysis of ontogenetic bite-force scaling among Crocodylia" type="journal article" year="2014">38</bibRefCitation>
|
||
</superScript>
|
||
). Apical tooth pressures (1 mm crown height) range from 718 to 2,974 MPa (104,137 to 431,342 pounds per square inch [psi]) (left M3 of
|
||
<materialsCitation ID-GBIF-Occurrence="2598005744" box="[1347,1438,1491,1513]" collectionCode="BHI" pageId="2" pageNumber="3" specimenCode="BHI 4100">BHI 4100</materialsCitation>
|
||
and right M5 of
|
||
<materialsCitation ID-GBIF-Occurrence="2598005751" box="[530,626,1518,1539]" collectionCode="MOR" pageId="2" pageNumber="3" specimenCode="MOR 980">MOR 980</materialsCitation>
|
||
, respectively) (
|
||
<httpUri box="[768,1000,1518,1540]" httpUri="https://static-content.springer.com/esm/art%3A10.1038%2Fs41598-017-02161-w/MediaObjects/41598_2017_2161_MOESM1_ESM.xls" pageId="2" pageNumber="3">Supplementary Table S2</httpUri>
|
||
). The larger values are the highest tooth pressures ever estimated (2,473 MPa [358,678 psi] was deduced for a 2.99 m bob-tailed
|
||
<taxonomicName authorityName="Schneider" authorityYear="1801" box="[1171,1271,1545,1566]" class="Reptilia" family="Crocodylidae" genus="Crocodylus" kingdom="Animalia" order="Crocodylia" pageId="2" pageNumber="3" phylum="Chordata" rank="species" species="porosus">
|
||
<emphasis box="[1171,1186,1545,1566]" italics="true" pageId="2" pageNumber="3">C</emphasis>
|
||
.
|
||
<emphasis box="[1198,1271,1545,1566]" italics="true" pageId="2" pageNumber="3">porosus</emphasis>
|
||
</taxonomicName>
|
||
<bibRefCitation author="Erickson, G. M." box="[1271,1278,1541,1555]" journalOrPublisher="PLoS ONE" pageId="2" pageNumber="3" pagination="e 31781" part="7" refId="ref7358" refString="8. Erickson, G. M. et al. Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation. PLoS ONE 7, e 31781, doi: 10.1371 / journal. pone. 0031781 (2012)." title="Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation" type="journal article" year="2012">
|
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<superScript attach="left" box="[1271,1278,1541,1555]" fontSize="6" pageId="2" pageNumber="3">8</superScript>
|
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</bibRefCitation>
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).
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[1298,1479,1545,1566]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="2" pageNumber="3" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1298,1479,1545,1566]" italics="true" pageId="2" pageNumber="3">Tyrannosaurus rex</emphasis>
|
||
</taxonomicName>
|
||
tooth pressures exceeded the ultimate shear stress of cortical bone (65–71 MPa
|
||
<superScript attach="left" box="[1159,1189,1568,1582]" fontSize="6" pageId="2" pageNumber="3">
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<bibRefCitation author="Carter, D. R. & Beaupre, G. S." bookContentInfo="318" box="[1159,1166,1568,1582]" journalOrPublisher="Cambridge Univ. Press" pageId="2" pageNumber="3" refId="ref7216" refString="4. Carter, D. R. & Beaupre, G. S. Skeletal Function and Form: Mechanobiology of Skeletal Development, Aging, and Regeneration 318 (Cambridge Univ. Press 2001)." title="Skeletal Function and Form: Mechanobiology of Skeletal Development, Aging, and Regeneration" type="book" year="2001">4</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Turner, C. H. & Wang, T. & Burr, D. B." box="[1174,1189,1568,1582]" journalOrPublisher="Calcif. Tissue Int." pageId="2" pageNumber="3" pagination="373 - 378" part="69" refId="ref8951" refString="39. Turner, C. H., Wang, T. & Burr, D. B. Shear strength and fatigue properties of human cortical bone determined from pure shear tests. Calcif. Tissue Int. 69, 373 - 378, doi: 10.1007 / s 00223 - 001 - 1006 - 1 (2001)." title="Shear strength and fatigue properties of human cortical bone determined from pure shear tests" type="journal article" year="2001">39</bibRefCitation>
|
||
</superScript>
|
||
[9,427–10,298 psi]) for at least 25 mm of crown height in nearly all maxillary teeth. One of the largest
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[1077,1131,1598,1620]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="2" pageNumber="3" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1077,1091,1599,1620]" italics="true" pageId="2" pageNumber="3">T</emphasis>
|
||
.
|
||
<emphasis box="[1102,1131,1599,1620]" italics="true" pageId="2" pageNumber="3">rex</emphasis>
|
||
</taxonomicName>
|
||
individuals (
|
||
<materialsCitation ID-GBIF-Occurrence="2598005748" box="[1253,1410,1598,1620]" collectionCode="FMNH" pageId="2" pageNumber="3" specimenCode="FMNH PR2081">FMNH PR 2081</materialsCitation>
|
||
) maintained such pressures up to (and presumably beyond) the 37 mm indentation maximum utilized in this study
|
||
<bibRefCitation author="DePalma, R. A. II. & Burnham, D. A. & Martin, L. D. & Rothschild, B. M. & Larson, P. L." box="[1449,1464,1621,1635]" journalOrPublisher="Proc. Nat. Acad. Sci. USA" pageId="2" pageNumber="3" pagination="12560 - 12564" part="110" refId="ref7711" refString="15. DePalma, R. A. II., Burnham, D. A., Martin, L. D., Rothschild, B. M. & Larson, P. L. Physical evidence of predatory behavior in Tyrannosaurus rex. Proc. Nat. Acad. Sci. USA 110, 12560 - 12564, doi: 10.1073 / pnas. 1216534110 (2013)." title="Physical evidence of predatory behavior in Tyrannosaurus rex" type="journal article" year="2013">
|
||
<superScript attach="left" box="[1449,1464,1621,1635]" fontSize="6" pageId="2" pageNumber="3">15</superScript>
|
||
</bibRefCitation>
|
||
.
|
||
</paragraph>
|
||
</subSubSection>
|
||
<subSubSection pageId="2" pageNumber="3" type="description">
|
||
<paragraph blockId="2.[415,1480,1140,1913]" pageId="2" pageNumber="3">
|
||
Analysis of dental-arcade configurations from
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[896,950,1652,1673]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="2" pageNumber="3" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[896,910,1652,1673]" italics="true" pageId="2" pageNumber="3">T</emphasis>
|
||
.
|
||
<emphasis box="[921,950,1652,1673]" italics="true" pageId="2" pageNumber="3">rex</emphasis>
|
||
</taxonomicName>
|
||
skulls shows that its palatal and dental anatomy would have promoted: (1) fractures during biting that spanned between the mesial and distal carinae of adjacent teeth due to localized stress concentrations (
|
||
<figureCitation box="[782,836,1704,1726]" captionStart="Figure 3" captionStartId="3.[415,480,1101,1123]" captionTargetBox="[415,1215,124,1066]" captionTargetId="figure@3.[415,1215,124,1066]" captionTargetPageId="3" captionText="Figure 3. Tyrannosaurus rex dental functional morphology. (A) Exemplar tooth pressures along the distal 37mm of the left M5 of BHI 3033 (warmer colours indicate higher pressures), illustrating bone-penetrating shear stresses (>65MPa4, 39) for almost 25mm of indentation depth. (B) Mesial and distal facing carinae (white arrows) helped direct pathways of bone fracture towards adjacent maxillary teeth (C) (ventral view of BHI 3033) that were also engaged during indentation, illustrating how the most procumbent maxillary tooth crowns collectively form a fracture arcade (pink arrows) due to pressures generated when biting. (Figure element in (A) derived from digital scan by Virtual Surfaces, Inc)." figureDoi="http://doi.org/10.5281/zenodo.3748937" httpUri="https://zenodo.org/record/3748937/files/figure.png" pageId="2" pageNumber="3">Fig. 3</figureCitation>
|
||
); and (2) numerous three- and four-point loading configurationsclassic means by which the tensional and shear weaknesses of beams (including bones) are exploited in mechanical and orthopaedic engineering with non-opposing loading points
|
||
<superScript attach="left" box="[1095,1143,1754,1769]" fontSize="6" pageId="2" pageNumber="3">
|
||
<bibRefCitation author="Carter, D. R. & Beaupre, G. S." bookContentInfo="318" box="[1095,1102,1754,1768]" journalOrPublisher="Cambridge Univ. Press" pageId="2" pageNumber="3" refId="ref7216" refString="4. Carter, D. R. & Beaupre, G. S. Skeletal Function and Form: Mechanobiology of Skeletal Development, Aging, and Regeneration 318 (Cambridge Univ. Press 2001)." title="Skeletal Function and Form: Mechanobiology of Skeletal Development, Aging, and Regeneration" type="book" year="2001">4</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Cochran, G. V. B." bookContentInfo="413" box="[1111,1118,1754,1768]" journalOrPublisher="Churchill Livingstone" pageId="2" pageNumber="3" refId="ref7254" refString="5. Cochran, G. V. B. A Primer of Orthopaedic Biomechanics 413 (Churchill Livingstone 1982)." title="A Primer of Orthopaedic Biomechanics" type="book" year="1982">5</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Erickson, G. M. & Catanese, J. III & Keaveny, T." box="[1127,1143,1754,1768]" journalOrPublisher="Anat. Rec." pageId="2" pageNumber="3" pagination="115 - 124" part="268" refId="ref9013" refString="40. Erickson, G. M., Catanese, J. III & Keaveny, T. Evolution of the biomechanical material properties of the femur. Anat. Rec. 268, 115 - 124, doi: 10.1002 / ar. 10145 (2002)." title="Evolution of the biomechanical material properties of the femur" type="journal article" year="2002">40</bibRefCitation>
|
||
</superScript>
|
||
. Three-point arrangements likely occurred: (1) between consecutive, large teeth along the dental arcade and the opposing tooth crown (
|
||
<figureCitation box="[1394,1465,1784,1806]" captionStart="Figure 4" captionStartId="4.[415,480,1406,1428]" captionTargetBox="[418,1052,127,1368]" captionTargetId="figure@4.[415,1055,124,1371]" captionTargetPageId="4" captionText="Figure 4. Jaw models of Tyrannosaurus rex paired with idealized beam diagrams, illustrating three- (A) (lateral view), (B) (anterior view) and four-point ((C), anterior view) loading configurations that allowed T. rex to promote failure stresses and fracture rigid structures (e.g., bone) without the aid of occluding dentitions. Teeth (cones) and the osseus palate, composed of the right and left maxillae and an anterior expansion of the vomer (rectangle), are shown as contact points in pink; original beam shapes are dark blue; and idealized plastic deformations (exaggerated) are light blue." figureDoi="http://doi.org/10.5281/zenodo.3748939" httpUri="https://zenodo.org/record/3748939/files/figure.png" pageId="2" pageNumber="3">Fig. 4A</figureCitation>
|
||
); and (2) between the lateral teeth and the anterior region of the bony palate, consisting of the right and left maxillae and an expanded portion of the fused vomers at the midline (see
|
||
<figureCitation box="[1086,1153,1838,1860]" captionStart="Figure 4" captionStartId="4.[415,480,1406,1428]" captionTargetBox="[418,1052,127,1368]" captionTargetId="figure@4.[415,1055,124,1371]" captionTargetPageId="4" captionText="Figure 4. Jaw models of Tyrannosaurus rex paired with idealized beam diagrams, illustrating three- (A) (lateral view), (B) (anterior view) and four-point ((C), anterior view) loading configurations that allowed T. rex to promote failure stresses and fracture rigid structures (e.g., bone) without the aid of occluding dentitions. Teeth (cones) and the osseus palate, composed of the right and left maxillae and an anterior expansion of the vomer (rectangle), are shown as contact points in pink; original beam shapes are dark blue; and idealized plastic deformations (exaggerated) are light blue." figureDoi="http://doi.org/10.5281/zenodo.3748939" httpUri="https://zenodo.org/record/3748939/files/figure.png" pageId="2" pageNumber="3">Fig. 4B</figureCitation>
|
||
), as can occur in other carnivores with reinforced palates such as crocodylians (P.M.G. and G.M.E., personal observations). Four-point loading likely occurred to bones spanning across both left and right upper and lower tooth rows (
|
||
<figureCitation box="[1257,1328,1891,1913]" captionStart="Figure 4" captionStartId="4.[415,480,1406,1428]" captionTargetBox="[418,1052,127,1368]" captionTargetId="figure@4.[415,1055,124,1371]" captionTargetPageId="4" captionText="Figure 4. Jaw models of Tyrannosaurus rex paired with idealized beam diagrams, illustrating three- (A) (lateral view), (B) (anterior view) and four-point ((C), anterior view) loading configurations that allowed T. rex to promote failure stresses and fracture rigid structures (e.g., bone) without the aid of occluding dentitions. Teeth (cones) and the osseus palate, composed of the right and left maxillae and an anterior expansion of the vomer (rectangle), are shown as contact points in pink; original beam shapes are dark blue; and idealized plastic deformations (exaggerated) are light blue." figureDoi="http://doi.org/10.5281/zenodo.3748939" httpUri="https://zenodo.org/record/3748939/files/figure.png" pageId="2" pageNumber="3">Fig. 4C</figureCitation>
|
||
).
|
||
</paragraph>
|
||
</subSubSection>
|
||
<caption ID-DOI="http://doi.org/10.5281/zenodo.3748937" ID-Zenodo-Dep="3748937" httpUri="https://zenodo.org/record/3748937/files/figure.png" pageId="3" pageNumber="4" startId="3.[415,480,1101,1123]" subCaptionStartIDs="3.[1265,1329,1234,1256]" subCaptionStarts="Figure e" targetBox="[415,1215,124,1066]" targetPageId="3">
|
||
<paragraph blockId="3.[415,1473,1101,1283]" pageId="3" pageNumber="4">
|
||
<emphasis bold="true" box="[415,503,1101,1123]" pageId="3" pageNumber="4">Figure 3.</emphasis>
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[515,690,1102,1123]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="3" pageNumber="4" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[515,690,1102,1123]" italics="true" pageId="3" pageNumber="4">Tyrannosaurus rex</emphasis>
|
||
</taxonomicName>
|
||
dental functional morphology. (
|
||
<emphasis bold="true" box="[1000,1017,1101,1122]" pageId="3" pageNumber="4">A</emphasis>
|
||
) Exemplar tooth pressures along the distal 37 mm of the left M5 of
|
||
<materialsCitation ID-GBIF-Occurrence="2598005740" box="[641,733,1128,1149]" collectionCode="BHI" pageId="3" pageNumber="4" specimenCode="BHI 3033">BHI 3033</materialsCitation>
|
||
(warmer colours indicate higher pressures), illustrating bone-penetrating shear stresses (>65 MPa
|
||
<superScript attach="left" box="[645,675,1151,1165]" fontSize="6" pageId="3" pageNumber="4">
|
||
<bibRefCitation author="Carter, D. R. & Beaupre, G. S." bookContentInfo="318" box="[645,652,1151,1165]" journalOrPublisher="Cambridge Univ. Press" pageId="3" pageNumber="4" refId="ref7216" refString="4. Carter, D. R. & Beaupre, G. S. Skeletal Function and Form: Mechanobiology of Skeletal Development, Aging, and Regeneration 318 (Cambridge Univ. Press 2001)." title="Skeletal Function and Form: Mechanobiology of Skeletal Development, Aging, and Regeneration" type="book" year="2001">4</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Turner, C. H. & Wang, T. & Burr, D. B." box="[660,675,1151,1165]" journalOrPublisher="Calcif. Tissue Int." pageId="3" pageNumber="4" pagination="373 - 378" part="69" refId="ref8951" refString="39. Turner, C. H., Wang, T. & Burr, D. B. Shear strength and fatigue properties of human cortical bone determined from pure shear tests. Calcif. Tissue Int. 69, 373 - 378, doi: 10.1007 / s 00223 - 001 - 1006 - 1 (2001)." title="Shear strength and fatigue properties of human cortical bone determined from pure shear tests" type="journal article" year="2001">39</bibRefCitation>
|
||
</superScript>
|
||
) for almost 25 mm of indentation depth. (
|
||
<emphasis bold="true" box="[1075,1090,1155,1176]" pageId="3" pageNumber="4">B</emphasis>
|
||
) Mesial and distal facing carinae (white arrows) helped direct pathways of bone fracture towards adjacent maxillary teeth (
|
||
<emphasis bold="true" box="[1197,1213,1181,1203]" pageId="3" pageNumber="4">C</emphasis>
|
||
) (ventral view of
|
||
<materialsCitation ID-GBIF-Occurrence="2598005746" collectionCode="BHI" pageId="3" pageNumber="4" specimenCode="BHI 3033">BHI 3033</materialsCitation>
|
||
) that were also engaged during indentation, illustrating how the most procumbent maxillary tooth crowns collectively form a fracture arcade (pink arrows) due to pressures generated when biting. (Figure element in (
|
||
<emphasis bold="true" box="[1448,1465,1234,1255]" pageId="3" pageNumber="4">A</emphasis>
|
||
) derived from digital scan by Virtual Surfaces, Inc).
|
||
</paragraph>
|
||
</caption>
|
||
<subSubSection lastPageId="7" lastPageNumber="8" pageId="3" pageNumber="4" type="discussion">
|
||
<paragraph blockId="3.[415,1480,1364,1950]" box="[415,549,1364,1390]" pageId="3" pageNumber="4">
|
||
<heading bold="true" box="[415,549,1364,1390]" fontSize="11" level="1" pageId="3" pageNumber="4" reason="0">
|
||
<emphasis bold="true" box="[415,549,1364,1390]" pageId="3" pageNumber="4">Discussion</emphasis>
|
||
</heading>
|
||
</paragraph>
|
||
<paragraph blockId="3.[415,1480,1364,1950]" pageId="3" pageNumber="4">
|
||
Our findings, coupled with evidence of
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[797,851,1396,1417]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="3" pageNumber="4" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[797,811,1396,1417]" italics="true" pageId="3" pageNumber="4">T</emphasis>
|
||
.
|
||
<emphasis box="[822,851,1396,1417]" italics="true" pageId="3" pageNumber="4">rex</emphasis>
|
||
</taxonomicName>
|
||
carcass utilization from bite marks, explain how this taxon along with other large North American tyrannosaurids comminuted bone in the absence of dental occlusion. The maximum adult
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[532,586,1449,1470]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="3" pageNumber="4" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[532,546,1449,1470]" italics="true" pageId="3" pageNumber="4">T</emphasis>
|
||
.
|
||
<emphasis box="[557,586,1449,1470]" italics="true" pageId="3" pageNumber="4">rex</emphasis>
|
||
</taxonomicName>
|
||
bite forces (18,014–34,522 N; 4,050–7,761 lb) reported here for seven specimens spanning the adult size range for the taxon (see
|
||
<tableCitation box="[749,819,1475,1497]" captionStart="Table 1" captionStartId="5.[415,469,401,422]" captionTargetBox="[423,903,134,368]" captionTargetId="graphics@5.[415,970,124,373]" captionTargetPageId="5" captionText="Table 1. Adult52 Tyrannosaurus rex specimens, head lengths (HL), head widths (HW), and bite forces (BF, in newtons [N]) estimated in this study (see Methods and Supplementary Table S2 for measurement details and forces at specific tooth positions; see main text for museum abbreviations)." httpUri="http://table.plazi.org/id/DF206665055ED610FE77FE262F37FE08" pageId="3" pageNumber="4" tableUuid="DF206665055ED610FE77FE262F37FE08">Table 1</tableCitation>
|
||
) are each moderately to considerably lower than previous estimates (35,000–300,984 N
|
||
<superScript attach="left" box="[596,654,1498,1513]" fontSize="6" pageId="3" pageNumber="4">
|
||
<bibRefCitation author="Meers, M. B." box="[596,611,1498,1512]" journalOrPublisher="Hist. Biol" pageId="3" pageNumber="4" pagination="1 - 12" part="16" refId="ref8385" refString="28. Meers, M. B. Maximum bite force and prey size of Tyrannosaurus rex and their relationships to the inference of feeding behavior. Hist. Biol 16, 1 - 12, doi: 10.1080 / 0891296021000050755 (2002)." title="Maximum bite force and prey size of Tyrannosaurus rex and their relationships to the inference of feeding behavior" type="journal article" year="2002">28</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Therrien, F. & Henderson, D. M. & Huff, C. B." box="[618,633,1498,1512]" editor="Carpenter, K." journalOrPublisher="Indiana Univ. Press" pageId="3" pageNumber="4" pagination="179 - 237" refId="ref8430" refString="29. Therrien, F., Henderson, D. M. & Huff, C. B. Bite me: biomechanical models of theropod mandibles and implications for feeding behavior in The Carnivorous Dinosaurs (ed. Carpenter, K.) 179 - 237 (Indiana Univ. Press 2005)." title="Bite me: biomechanical models of theropod mandibles and implications for feeding behavior in The Carnivorous Dinosaurs" type="book" year="2005">29</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Bates, K. T. & Falkingham, P. L." box="[639,654,1498,1512]" journalOrPublisher="Biol. Lett." pageId="3" pageNumber="4" pagination="660 - 664" part="8" refId="ref8542" refString="31. Bates, K. T. & Falkingham, P. L. Estimating maximum bite performance in Tyrannosaurus rex using multi-body dynamics. Biol. Lett. 8, 660 - 664, doi: 10.1098 / rsbl. 2012.0056 (2012)." title="Estimating maximum bite performance in Tyrannosaurus rex using multi-body dynamics" type="journal article" year="2012">31</bibRefCitation>
|
||
</superScript>
|
||
; 7,869–67,667 lb). We suspect the differences stem primarily from previous models not implementing archosaurian-specific, jaw-closing musculature and force generation as well as not utilizing experimentally validated neontological models
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[815,830,1552,1566]" journalOrPublisher="J. Zool." pageId="3" pageNumber="4" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[815,830,1552,1566]" fontSize="6" pageId="3" pageNumber="4">35</superScript>
|
||
</bibRefCitation>
|
||
. Nonetheless, the values we estimate are still prodigious. Adductor forces introduced tooth pressures substantially higher than the ultimate shear stress of cortical bone, even at great depth, allowing deep penetration of impacted bones. Tooth penetration served to drive open cracks (engendered first by localized fractures at tooth contact points), using broadly expanding tooth crowns
|
||
<bibRefCitation author="Lucas, P. W." bookContentInfo="335" box="[1287,1302,1632,1646]" journalOrPublisher="Cambridge Univ. Press" pageId="3" pageNumber="4" refId="ref9063" refString="41. Lucas, P. W. Dental Functional Morphology: How Teeth Work 335 (Cambridge Univ. Press 2004)." title="Dental Functional Morphology: How Teeth Work" type="book" year="2004">
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||
<superScript attach="left" box="[1287,1302,1632,1646]" fontSize="6" pageId="3" pageNumber="4">41</superScript>
|
||
</bibRefCitation>
|
||
. Carinae accentuated these stresses and directed crack propagation towards adjacent teeth, resulting in high-pressure fracture arcades as cracks from the broadest and most procumbent teeth intersected during biting (
|
||
<figureCitation box="[1314,1371,1688,1710]" captionStart="Figure 3" captionStartId="3.[415,480,1101,1123]" captionTargetBox="[415,1215,124,1066]" captionTargetId="figure@3.[415,1215,124,1066]" captionTargetPageId="3" captionText="Figure 3. Tyrannosaurus rex dental functional morphology. (A) Exemplar tooth pressures along the distal 37mm of the left M5 of BHI 3033 (warmer colours indicate higher pressures), illustrating bone-penetrating shear stresses (>65MPa4, 39) for almost 25mm of indentation depth. (B) Mesial and distal facing carinae (white arrows) helped direct pathways of bone fracture towards adjacent maxillary teeth (C) (ventral view of BHI 3033) that were also engaged during indentation, illustrating how the most procumbent maxillary tooth crowns collectively form a fracture arcade (pink arrows) due to pressures generated when biting. (Figure element in (A) derived from digital scan by Virtual Surfaces, Inc)." figureDoi="http://doi.org/10.5281/zenodo.3748937" httpUri="https://zenodo.org/record/3748937/files/figure.png" pageId="3" pageNumber="4">Fig. 3</figureCitation>
|
||
). Together the dental and palatal anatomy also provided for three- and four-point loading configurations that facilitated localized and whole-element bone shear (
|
||
<figureCitation box="[818,873,1742,1764]" captionStart="Figure 4" captionStartId="4.[415,480,1406,1428]" captionTargetBox="[418,1052,127,1368]" captionTargetId="figure@4.[415,1055,124,1371]" captionTargetPageId="4" captionText="Figure 4. Jaw models of Tyrannosaurus rex paired with idealized beam diagrams, illustrating three- (A) (lateral view), (B) (anterior view) and four-point ((C), anterior view) loading configurations that allowed T. rex to promote failure stresses and fracture rigid structures (e.g., bone) without the aid of occluding dentitions. Teeth (cones) and the osseus palate, composed of the right and left maxillae and an anterior expansion of the vomer (rectangle), are shown as contact points in pink; original beam shapes are dark blue; and idealized plastic deformations (exaggerated) are light blue." figureDoi="http://doi.org/10.5281/zenodo.3748939" httpUri="https://zenodo.org/record/3748939/files/figure.png" pageId="3" pageNumber="4">Fig. 4</figureCitation>
|
||
). (Although not testable in our modelling, catastrophic explosion of some bones, particularly smaller elements or those with thin cortices, may have also occurred due to the introduction of strain energy densities exceeding the limits of bone
|
||
<bibRefCitation author="Carter, D. R. & Beaupre, G. S." bookContentInfo="318" box="[1047,1054,1792,1806]" journalOrPublisher="Cambridge Univ. Press" pageId="3" pageNumber="4" refId="ref7216" refString="4. Carter, D. R. & Beaupre, G. S. Skeletal Function and Form: Mechanobiology of Skeletal Development, Aging, and Regeneration 318 (Cambridge Univ. Press 2001)." title="Skeletal Function and Form: Mechanobiology of Skeletal Development, Aging, and Regeneration" type="book" year="2001">
|
||
<superScript attach="left" box="[1047,1054,1792,1806]" fontSize="6" pageId="3" pageNumber="4">4</superScript>
|
||
</bibRefCitation>
|
||
). Following fracture, repetitive and localized carnivoran-like biting (evidenced from bite marks;
|
||
<figureCitation box="[904,957,1822,1844]" captionStart="Figure 1" captionStartId="1.[415,479,639,661]" captionTargetBox="[415,1055,124,604]" captionTargetId="figure@1.[415,1055,124,604]" captionTargetPageId="1" captionText="Figure 1. Left ilium of Triceratops sp. (MOR 799) in ventrolateral view with ~80 bite marks attributed to Tyrannosaurus rex. A large portion (~17%) of the iliac crest was removed (bracketed) by repetitive, localized biting." figureDoi="http://doi.org/10.5281/zenodo.3748933" httpUri="https://zenodo.org/record/3748933/files/figure.png" pageId="3" pageNumber="4">Fig. 1</figureCitation>
|
||
) served to accentuate fine-scale fragmentation, expose bone surfaces, and liberate marrow for rapid digestion by low pH stomach acids
|
||
<bibRefCitation author="Chin, K. & Tokaryk, T. T. & Erickson, G. M. & Calk, L. C." box="[1171,1186,1845,1859]" journalOrPublisher="Nature" pageId="3" pageNumber="4" pagination="680 - 682" part="393" refId="ref8109" refString="22. Chin, K., Tokaryk, T. T., Erickson, G. M. & Calk, L. C. A king-sized theropod coprolite. Nature 393, 680 - 682, doi: 10.1038 / 31461 (1998)." title="A king-sized theropod coprolite" type="journal article" year="1998">
|
||
<superScript attach="left" box="[1171,1186,1845,1859]" fontSize="6" pageId="3" pageNumber="4">22</superScript>
|
||
</bibRefCitation>
|
||
.
|
||
</paragraph>
|
||
<paragraph blockId="3.[415,1480,1364,1950]" lastBlockId="4.[415,1479,1645,1964]" lastPageId="4" lastPageNumber="5" pageId="3" pageNumber="4">
|
||
The few osteophagous reptiles capable of driving cracks through bones, such as adult crocodylians
|
||
<superScript attach="left" box="[1406,1437,1872,1886]" fontSize="6" pageId="3" pageNumber="4">
|
||
<bibRefCitation author="Erickson, G. M." box="[1406,1413,1872,1886]" journalOrPublisher="PLoS ONE" pageId="3" pageNumber="4" pagination="e 31781" part="7" refId="ref7358" refString="8. Erickson, G. M. et al. Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation. PLoS ONE 7, e 31781, doi: 10.1371 / journal. pone. 0031781 (2012)." title="Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation" type="journal article" year="2012">8</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1422,1437,1872,1886]" journalOrPublisher="J. Zool." pageId="3" pageNumber="4" pagination="123 - 142" part="295" refId="ref8634" refString="33. Gignac, P. M. & Erickson, G. M. Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators. J. Zool. 295, 123 - 142, doi: 10.1111 / jzo. 12187 (2015)." title="Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators" type="journal article" year="2015">33</bibRefCitation>
|
||
</superScript>
|
||
and tyrannosaurids, have force-resistant, thecodont dentitions. However, because of their characteristically offset dental rows, reptiles tend to generate a mechanical couple while biting (e.g., opposing but equal forces acting in parallel around a single axis; for an illustration see pages 19–20 in Cochran
|
||
<bibRefCitation author="Cochran, G. V. B." bookContentInfo="413" box="[1153,1160,1645,1659]" journalOrPublisher="Churchill Livingstone" pageId="4" pageNumber="5" refId="ref7254" refString="5. Cochran, G. V. B. A Primer of Orthopaedic Biomechanics 413 (Churchill Livingstone 1982)." title="A Primer of Orthopaedic Biomechanics" type="book" year="1982">
|
||
<superScript attach="left" box="[1153,1160,1645,1659]" fontSize="6" pageId="4" pageNumber="5">5</superScript>
|
||
</bibRefCitation>
|
||
), which can rotate isolated bones or those within carcasses and, potentially, load tooth crowns in unexpected ways. Such loads may induce reaction forces that can cause permanent structural failure
|
||
<superScript attach="left" box="[947,985,1698,1713]" fontSize="6" pageId="4" pageNumber="5">
|
||
<bibRefCitation author="Lucas, P. W." bookContentInfo="335" box="[947,962,1698,1712]" journalOrPublisher="Cambridge Univ. Press" pageId="4" pageNumber="5" refId="ref9063" refString="41. Lucas, P. W. Dental Functional Morphology: How Teeth Work 335 (Cambridge Univ. Press 2004)." title="Dental Functional Morphology: How Teeth Work" type="book" year="2004">41</bibRefCitation>
|
||
–
|
||
<bibRefCitation author="Erickson, G. M." box="[970,985,1698,1712]" journalOrPublisher="Copeia." pageId="4" pageNumber="5" pagination="739 - 743" part="1996" refId="ref9135" refString="43. Erickson, G. M. Toothlessness in American alligators. Copeia. 1996, 739 - 743, doi: 10.2307 / 1447542 (1996)." title="Toothlessness in American alligators" type="journal article" year="1996">43</bibRefCitation>
|
||
</superScript>
|
||
. Unexpected loads are counteracted by possessing semi-conical crowns with high, transverse-plane area moments of inertia. Such teeth are capable of sustaining comparable loads from any direction
|
||
<superScript attach="left" box="[774,834,1752,1766]" fontSize="6" pageId="4" pageNumber="5">
|
||
<bibRefCitation author="Erickson, G. M. & Lappin, A. K. & Vliet, K. A." box="[774,789,1752,1766]" journalOrPublisher="J. Zool. Lond" pageId="4" pageNumber="5" pagination="317 - 327" part="260" refId="ref8486" refString="30. Erickson, G. M., Lappin, A. K. & Vliet, K. A. The ontogeny of bite-force performance in American alligator (Alligator mississippiensis). J. Zool. Lond 260, 317 - 327, doi: 10.1017 / S 0952836903003819 (2003)." title="The ontogeny of bite-force performance in American alligator (Alligator mississippiensis)" type="journal article" year="2003">30</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[797,812,1752,1766]" journalOrPublisher="J. Zool." pageId="4" pageNumber="5" pagination="123 - 142" part="295" refId="ref8634" refString="33. Gignac, P. M. & Erickson, G. M. Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators. J. Zool. 295, 123 - 142, doi: 10.1111 / jzo. 12187 (2015)." title="Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators" type="journal article" year="2015">33</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Wainwright, S. A. & Biggs, W. D. & Currey, J. D. & Gosline, J. M." bookContentInfo="423" box="[819,834,1752,1766]" journalOrPublisher="Princeton Univ. Press, Princeton, NJ" pageId="4" pageNumber="5" refId="ref9165" refString="44. Wainwright, S. A., Biggs, W. D., Currey, J. D. & Gosline, J. M. Mechanical Design in Organisms. pp 423, (Princeton Univ. Press, Princeton, NJ 1976)." title="Mechanical Design in Organisms" type="book" year="1976">44</bibRefCitation>
|
||
</superScript>
|
||
, prolonging their functionality until replacement (e.g., over a year for large adult crocodylians
|
||
<superScript attach="left" box="[676,713,1778,1793]" fontSize="6" pageId="4" pageNumber="5">
|
||
<bibRefCitation author="Erickson, G. M." box="[676,691,1778,1792]" journalOrPublisher="Proc. Nat. Acad. Sci. USA" pageId="4" pageNumber="5" pagination="14623 - 14627" part="93" refId="ref8215" refString="24. Erickson, G. M. Incremental lines of von Ebner in dinosaurs and the assessment of tooth replacement rates using growth line counts. Proc. Nat. Acad. Sci. USA 93, 14623 - 14627, doi: 10.1073 / pnas. 93.25.14623 (1996)." title="Incremental lines of von Ebner in dinosaurs and the assessment of tooth replacement rates using growth line counts" type="journal article" year="1996">24</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Brueggen, J." box="[698,713,1778,1792]" journalOrPublisher="Croc. Spec. Grp. Newsl." pageId="4" pageNumber="5" pagination="17 - 18" part="25" refId="ref9214" refString="45. Brueggen, J. Crocodilian tooth replacement. Croc. Spec. Grp. Newsl. 25, 17 - 18 (2006)." title="Crocodilian tooth replacement" type="journal article" year="2006">45</bibRefCitation>
|
||
</superScript>
|
||
and ~777 days for
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[894,948,1782,1804]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="4" pageNumber="5" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[894,908,1783,1804]" italics="true" pageId="4" pageNumber="5">T</emphasis>
|
||
.
|
||
<emphasis box="[919,948,1783,1804]" italics="true" pageId="4" pageNumber="5">rex</emphasis>
|
||
</taxonomicName>
|
||
<bibRefCitation author="Erickson, G. M." box="[949,964,1778,1792]" journalOrPublisher="Proc. Nat. Acad. Sci. USA" pageId="4" pageNumber="5" pagination="14623 - 14627" part="93" refId="ref8215" refString="24. Erickson, G. M. Incremental lines of von Ebner in dinosaurs and the assessment of tooth replacement rates using growth line counts. Proc. Nat. Acad. Sci. USA 93, 14623 - 14627, doi: 10.1073 / pnas. 93.25.14623 (1996)." title="Incremental lines of von Ebner in dinosaurs and the assessment of tooth replacement rates using growth line counts" type="journal article" year="1996">
|
||
<superScript attach="right" box="[949,964,1778,1792]" fontSize="6" pageId="4" pageNumber="5">24</superScript>
|
||
</bibRefCitation>
|
||
) in these polyphodont taxa
|
||
<bibRefCitation author="Erickson, G. M." box="[1226,1241,1778,1792]" journalOrPublisher="Proc. Nat. Acad. Sci. USA" pageId="4" pageNumber="5" pagination="14623 - 14627" part="93" refId="ref8215" refString="24. Erickson, G. M. Incremental lines of von Ebner in dinosaurs and the assessment of tooth replacement rates using growth line counts. Proc. Nat. Acad. Sci. USA 93, 14623 - 14627, doi: 10.1073 / pnas. 93.25.14623 (1996)." title="Incremental lines of von Ebner in dinosaurs and the assessment of tooth replacement rates using growth line counts" type="journal article" year="1996">
|
||
<superScript attach="left" box="[1226,1241,1778,1792]" fontSize="6" pageId="4" pageNumber="5">24</superScript>
|
||
</bibRefCitation>
|
||
. Taken together with the aforementioned prodigious bite forces, tooth pressures, localized biting, and absence of mammal-like, precise dental occlusion, our findings indicate that the extensive fragmentation of bone practiced by large tyrannosaurids was directly facilitated by their elongate, semi-conical, carinated, rooted, and polyphyodont dental arcades.
|
||
</paragraph>
|
||
<caption ID-DOI="http://doi.org/10.5281/zenodo.3748939" ID-Zenodo-Dep="3748939" httpUri="https://zenodo.org/record/3748939/files/figure.png" pageId="4" pageNumber="5" startId="4.[415,480,1406,1428]" subCaptionStartIDs="4.[1076,1215,1433,1455]" subCaptionStarts="figu" targetBox="[418,1052,127,1368]" targetPageId="4">
|
||
<paragraph blockId="4.[415,1471,1406,1562]" pageId="4" pageNumber="5">
|
||
<emphasis bold="true" box="[415,503,1406,1428]" pageId="4" pageNumber="5">Figure 4.</emphasis>
|
||
Jaw models of
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[652,828,1407,1428]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="4" pageNumber="5" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[652,828,1407,1428]" italics="true" pageId="4" pageNumber="5">Tyrannosaurus rex</emphasis>
|
||
</taxonomicName>
|
||
paired with idealized beam diagrams, illustrating three- (
|
||
<emphasis bold="true" box="[1374,1391,1406,1427]" pageId="4" pageNumber="5">A</emphasis>
|
||
) (lateral view), (
|
||
<emphasis bold="true" box="[486,501,1433,1454]" pageId="4" pageNumber="5">B</emphasis>
|
||
) (anterior view) and four-point ((
|
||
<emphasis bold="true" box="[825,841,1433,1455]" pageId="4" pageNumber="5">C</emphasis>
|
||
), anterior view) loading configurations that allowed
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[1341,1395,1433,1455]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="4" pageNumber="5" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1341,1355,1434,1455]" italics="true" pageId="4" pageNumber="5">T</emphasis>
|
||
.
|
||
<emphasis box="[1366,1395,1434,1455]" italics="true" pageId="4" pageNumber="5">rex</emphasis>
|
||
</taxonomicName>
|
||
to promote failure stresses and fracture rigid structures (e.g., bone) without the aid of occluding dentitions. Teeth (cones) and the osseus palate, composed of the right and left maxillae and an anterior expansion of the vomer (rectangle), are shown as contact points in pink; original beam shapes are dark blue; and idealized plastic deformations (exaggerated) are light blue.
|
||
</paragraph>
|
||
</caption>
|
||
<paragraph blockId="4.[415,1479,1645,1964]" lastBlockId="5.[415,1481,540,1176]" lastPageId="5" lastPageNumber="6" pageId="4" pageNumber="5">
|
||
It is intriguing that the maximum tooth pressures shown here for
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[1082,1137,1889,1910]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="4" pageNumber="5" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1082,1096,1889,1910]" italics="true" pageId="4" pageNumber="5">T</emphasis>
|
||
.
|
||
<emphasis box="[1108,1137,1889,1910]" italics="true" pageId="4" pageNumber="5">rex</emphasis>
|
||
</taxonomicName>
|
||
overlap tightly with those reported for large adult crocodylians (e.g.,
|
||
<taxonomicName baseAuthorityName="Daudin" baseAuthorityYear="1802" box="[737,909,1916,1937]" class="Reptilia" family="Alligatoridae" genus="Alligator" kingdom="Animalia" order="Crocodylia" pageId="4" pageNumber="5" phylum="Chordata" rank="species" species="mississippiensis">
|
||
<emphasis box="[737,753,1916,1937]" italics="true" pageId="4" pageNumber="5">A</emphasis>
|
||
.
|
||
<emphasis box="[764,909,1916,1937]" italics="true" pageId="4" pageNumber="5">mississippiensis</emphasis>
|
||
</taxonomicName>
|
||
,
|
||
<taxonomicName authorityName="Schneider" authorityYear="1801" box="[921,1019,1916,1937]" class="Reptilia" family="Crocodylidae" genus="Crocodylus" kingdom="Animalia" order="Crocodylia" pageId="4" pageNumber="5" phylum="Chordata" rank="species" species="porosus">
|
||
<emphasis box="[921,936,1916,1937]" italics="true" pageId="4" pageNumber="5">C</emphasis>
|
||
.
|
||
<emphasis box="[947,1019,1916,1937]" italics="true" pageId="4" pageNumber="5">porosus</emphasis>
|
||
</taxonomicName>
|
||
) that are also capable of fracturing bone during feeding
|
||
<superScript attach="left" box="[486,515,1938,1953]" fontSize="6" pageId="4" pageNumber="5">
|
||
<bibRefCitation author="Erickson, G. M." box="[486,493,1938,1952]" journalOrPublisher="PLoS ONE" pageId="4" pageNumber="5" pagination="e 31781" part="7" refId="ref7358" refString="8. Erickson, G. M. et al. Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation. PLoS ONE 7, e 31781, doi: 10.1371 / journal. pone. 0031781 (2012)." title="Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation" type="journal article" year="2012">8</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[500,515,1938,1952]" journalOrPublisher="J. Zool." pageId="4" pageNumber="5" pagination="123 - 142" part="295" refId="ref8634" refString="33. Gignac, P. M. & Erickson, G. M. Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators. J. Zool. 295, 123 - 142, doi: 10.1111 / jzo. 12187 (2015)." title="Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators" type="journal article" year="2015">33</bibRefCitation>
|
||
</superScript>
|
||
(although not sequentially). Even though extant crocodylians are considerably smaller than adults of
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[415,468,541,562]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="5" pageNumber="6" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[415,429,541,562]" italics="true" pageId="5" pageNumber="6">T</emphasis>
|
||
.
|
||
<emphasis box="[439,468,541,562]" italics="true" pageId="5" pageNumber="6">rex</emphasis>
|
||
</taxonomicName>
|
||
, both groups generate bone-failing pressures (e.g., crocodylian and
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[1101,1154,541,562]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="5" pageNumber="6" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1101,1115,541,562]" italics="true" pageId="5" pageNumber="6">T</emphasis>
|
||
.
|
||
<emphasis box="[1125,1154,541,562]" italics="true" pageId="5" pageNumber="6">rex</emphasis>
|
||
</taxonomicName>
|
||
tooth pressures at the distal crown of the most procumbent crushing teeth range from 309–2,473 MPa
|
||
<superScript attach="left" box="[1053,1083,564,578]" fontSize="6" pageId="5" pageNumber="6">
|
||
<bibRefCitation author="Erickson, G. M." box="[1053,1060,564,578]" journalOrPublisher="PLoS ONE" pageId="5" pageNumber="6" pagination="e 31781" part="7" refId="ref7358" refString="8. Erickson, G. M. et al. Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation. PLoS ONE 7, e 31781, doi: 10.1371 / journal. pone. 0031781 (2012)." title="Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation" type="journal article" year="2012">8</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1068,1083,564,578]" journalOrPublisher="J. Zool." pageId="5" pageNumber="6" pagination="123 - 142" part="295" refId="ref8634" refString="33. Gignac, P. M. & Erickson, G. M. Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators. J. Zool. 295, 123 - 142, doi: 10.1111 / jzo. 12187 (2015)." title="Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators" type="journal article" year="2015">33</bibRefCitation>
|
||
</superScript>
|
||
[44,817–358,678 psi] and 718–2,974 MPa [104,137–431,342 psi] [
|
||
<httpUri box="[635,868,594,616]" httpUri="https://static-content.springer.com/esm/art%3A10.1038%2Fs41598-017-02161-w/MediaObjects/41598_2017_2161_MOESM1_ESM.xls" pageId="5" pageNumber="6">Supplementary Table S2</httpUri>
|
||
], respectively), using teeth with relatively thin enamel shells
|
||
<superScript attach="left" box="[1442,1479,590,605]" fontSize="6" pageId="5" pageNumber="6">
|
||
<bibRefCitation author="Farlow, J. O. & Brinkman, D. L." box="[1442,1457,590,604]" editor="Rosenberg, D. L. & Wolberg, D. L." journalOrPublisher="Univ. of Tennessee Dept. Geological Sciences" pageId="5" pageNumber="6" pagination="165 - 175" refId="ref7784" refString="16. Farlow, J. O. & Brinkman, D. L. Wear surfaces on the teeth of tyrannosaurs in The Paleontological Society Special Publication (eds Rosenberg, D. L. & Wolberg, D. L.) 165 - 175 (Univ. of Tennessee Dept. Geological Sciences 1994)." title="Wear surfaces on the teeth of tyrannosaurs in The Paleontological Society Special Publication" type="book" year="1994">16</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Enax, J." box="[1464,1479,590,604]" journalOrPublisher="J. Struct. Biol." pageId="5" pageNumber="6" pagination="155 - 163" part="184" refId="ref9241" refString="46. Enax, J. et al. Characterization of crocodile teeth: correlation of composition, microstructure, and hardness. J. Struct. Biol. 184, 155 - 163, doi: 10.1016 / j. jsb. 2013.09.018 (2013)." title="Characterization of crocodile teeth: correlation of composition, microstructure, and hardness" type="journal article" year="2013">46</bibRefCitation>
|
||
</superScript>
|
||
(e.g.,
|
||
<taxonomicName baseAuthorityName="Daudin" baseAuthorityYear="1802" box="[468,643,621,642]" class="Reptilia" family="Alligatoridae" genus="Alligator" kingdom="Animalia" order="Crocodylia" pageId="5" pageNumber="6" phylum="Chordata" rank="species" species="mississippiensis">
|
||
<emphasis box="[468,484,621,642]" italics="true" pageId="5" pageNumber="6">A</emphasis>
|
||
.
|
||
<emphasis box="[496,643,621,642]" italics="true" pageId="5" pageNumber="6">mississippiensis</emphasis>
|
||
</taxonomicName>
|
||
and
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[691,748,621,642]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="5" pageNumber="6" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[691,705,621,642]" italics="true" pageId="5" pageNumber="6">T</emphasis>
|
||
.
|
||
<emphasis box="[718,748,621,642]" italics="true" pageId="5" pageNumber="6">rex</emphasis>
|
||
</taxonomicName>
|
||
mean ± standard error of enamel thicknesses sampled along the crown are 237 ± 6 and 223 ± 30 microns, respectively; GME unpublished data). In the case of crocodylians, the enamel shell is only slightly stronger than the tooth pressures that are typically endured during feeding (e.g., tooth safety factors—how mechanically overbuilt a structure is versus its function
|
||
<bibRefCitation author="Carter, D. R. & Beaupre, G. S." bookContentInfo="318" box="[1086,1093,697,711]" journalOrPublisher="Cambridge Univ. Press" pageId="5" pageNumber="6" refId="ref7216" refString="4. Carter, D. R. & Beaupre, G. S. Skeletal Function and Form: Mechanobiology of Skeletal Development, Aging, and Regeneration 318 (Cambridge Univ. Press 2001)." title="Skeletal Function and Form: Mechanobiology of Skeletal Development, Aging, and Regeneration" type="book" year="2001">
|
||
<superScript attach="right" box="[1086,1093,697,711]" fontSize="6" pageId="5" pageNumber="6">4</superScript>
|
||
</bibRefCitation>
|
||
—range from 1.0–
|
||
<superScript attach="none" box="[1299,1329,697,711]" fontSize="6" pageId="5" pageNumber="6">
|
||
1.48,
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1314,1329,697,711]" journalOrPublisher="J. Zool." pageId="5" pageNumber="6" pagination="123 - 142" part="295" refId="ref8634" refString="33. Gignac, P. M. & Erickson, G. M. Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators. J. Zool. 295, 123 - 142, doi: 10.1111 / jzo. 12187 (2015)." title="Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators" type="journal article" year="2015">33</bibRefCitation>
|
||
</superScript>
|
||
), and apical tip spalls
|
||
<bibRefCitation author="Erickson, G. M." box="[470,485,724,738]" journalOrPublisher="Copeia." pageId="5" pageNumber="6" pagination="739 - 743" part="1996" refId="ref9135" refString="43. Erickson, G. M. Toothlessness in American alligators. Copeia. 1996, 739 - 743, doi: 10.2307 / 1447542 (1996)." title="Toothlessness in American alligators" type="journal article" year="1996">
|
||
<superScript attach="left" box="[470,485,724,738]" fontSize="6" pageId="5" pageNumber="6">43</superScript>
|
||
</bibRefCitation>
|
||
are structurally similarly to those documented previously in
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[1084,1140,728,749]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="5" pageNumber="6" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1084,1098,728,749]" italics="true" pageId="5" pageNumber="6">T</emphasis>
|
||
.
|
||
<emphasis box="[1110,1140,728,749]" italics="true" pageId="5" pageNumber="6">rex</emphasis>
|
||
</taxonomicName>
|
||
<bibRefCitation author="Farlow, J. O. & Brinkman, D. L." box="[1140,1155,724,738]" editor="Rosenberg, D. L. & Wolberg, D. L." journalOrPublisher="Univ. of Tennessee Dept. Geological Sciences" pageId="5" pageNumber="6" pagination="165 - 175" refId="ref7784" refString="16. Farlow, J. O. & Brinkman, D. L. Wear surfaces on the teeth of tyrannosaurs in The Paleontological Society Special Publication (eds Rosenberg, D. L. & Wolberg, D. L.) 165 - 175 (Univ. of Tennessee Dept. Geological Sciences 1994)." title="Wear surfaces on the teeth of tyrannosaurs in The Paleontological Society Special Publication" type="book" year="1994">
|
||
<superScript attach="left" box="[1140,1155,724,738]" fontSize="6" pageId="5" pageNumber="6">16</superScript>
|
||
</bibRefCitation>
|
||
. In the context of our integrative analysis, this functional convergence suggests that: (1) the performance capacities elucidated by this study are realistic; and (2)
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[580,637,781,802]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="5" pageNumber="6" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[580,594,781,802]" italics="true" pageId="5" pageNumber="6">T</emphasis>
|
||
.
|
||
<emphasis box="[607,637,781,802]" italics="true" pageId="5" pageNumber="6">rex</emphasis>
|
||
</taxonomicName>
|
||
tooth crowns would be unlikely to sustain bite forces that are substantially greater
|
||
<superScript attach="left" box="[1441,1479,777,791]" fontSize="6" pageId="5" pageNumber="6">
|
||
<bibRefCitation author="Meers, M. B." box="[1441,1456,777,791]" journalOrPublisher="Hist. Biol" pageId="5" pageNumber="6" pagination="1 - 12" part="16" refId="ref8385" refString="28. Meers, M. B. Maximum bite force and prey size of Tyrannosaurus rex and their relationships to the inference of feeding behavior. Hist. Biol 16, 1 - 12, doi: 10.1080 / 0891296021000050755 (2002)." title="Maximum bite force and prey size of Tyrannosaurus rex and their relationships to the inference of feeding behavior" type="journal article" year="2002">28</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Therrien, F. & Henderson, D. M. & Huff, C. B." box="[1464,1479,777,791]" editor="Carpenter, K." journalOrPublisher="Indiana Univ. Press" pageId="5" pageNumber="6" pagination="179 - 237" refId="ref8430" refString="29. Therrien, F., Henderson, D. M. & Huff, C. B. Bite me: biomechanical models of theropod mandibles and implications for feeding behavior in The Carnivorous Dinosaurs (ed. Carpenter, K.) 179 - 237 (Indiana Univ. Press 2005)." title="Bite me: biomechanical models of theropod mandibles and implications for feeding behavior in The Carnivorous Dinosaurs" type="book" year="2005">29</bibRefCitation>
|
||
</superScript>
|
||
than those reported here. Notably, juvenile crocodylians with smaller and less robust dentitions are incapable of rupturing large bones
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[625,640,830,844]" journalOrPublisher="J. Zool." pageId="5" pageNumber="6" pagination="123 - 142" part="295" refId="ref8634" refString="33. Gignac, P. M. & Erickson, G. M. Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators. J. Zool. 295, 123 - 142, doi: 10.1111 / jzo. 12187 (2015)." title="Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators" type="journal article" year="2015">
|
||
<superScript attach="left" box="[625,640,830,844]" fontSize="6" pageId="5" pageNumber="6">33</superScript>
|
||
</bibRefCitation>
|
||
, which is also consistent with crown morphologies and bite marks from juvenile
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[1424,1478,834,856]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="5" pageNumber="6" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1424,1438,835,856]" italics="true" pageId="5" pageNumber="6">T</emphasis>
|
||
.
|
||
<emphasis box="[1449,1478,835,856]" italics="true" pageId="5" pageNumber="6">rex</emphasis>
|
||
</taxonomicName>
|
||
that similarly do not show evidence of bone removal. Instead these consist of only shallow punctures and scores
|
||
<bibRefCitation author="Longrich, N. R. & Horner, J. R. & Erickson, G. M. & Currie, P. J." box="[1459,1474,857,871]" journalOrPublisher="PLoS ONE" pageId="5" pageNumber="6" pagination="e 13419" part="5" refId="ref8014" refString="20. Longrich, N. R., Horner, J. R., Erickson, G. M. & Currie, P. J. Cannibalism in Tyrannosaurus rex. PLoS ONE 5, e 13419, doi: 10.1371 / journal. pone. 0013419 (2010)." title="Cannibalism in Tyrannosaurus rex" type="journal article" year="2010">
|
||
<superScript attach="right" box="[1459,1474,857,871]" fontSize="6" pageId="5" pageNumber="6">20</superScript>
|
||
</bibRefCitation>
|
||
. Expansion of our protocol throughout ontogeny will help to elucidate at what size and age
|
||
<superScript attach="left" box="[1253,1289,884,898]" fontSize="6" pageId="5" pageNumber="6">
|
||
<bibRefCitation author="Erickson, G. M." box="[1253,1268,884,898]" journalOrPublisher="Nature" pageId="5" pageNumber="6" pagination="706 - 708" part="382" refId="ref8268" refString="25. Erickson, G. M. et al. Bite-force estimation for Tyrannosaurus rex from tooth-marked bones. Nature 382, 706 - 708, doi: 10.1038 / 382706 a 0 (1996)." title="Bite-force estimation for Tyrannosaurus rex from tooth-marked bones" type="journal article" year="1996">25</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Erickson, G. M." box="[1274,1289,884,898]" journalOrPublisher="Nature" pageId="5" pageNumber="6" pagination="772 - 775" part="430" refId="ref9289" refString="47. Erickson, G. M. et al. Gigantism and comparative life-history parameters of tyrannosaurid dinosaurs. Nature 430, 772 - 775, doi: 10.1038 / nature 02699 (2004)." title="Gigantism and comparative life-history parameters of tyrannosaurid dinosaurs" type="journal article" year="2004">47</bibRefCitation>
|
||
</superScript>
|
||
this taxon’s capacity for bone fragmentation first occurred.
|
||
</paragraph>
|
||
<paragraph pageId="5" pageNumber="6">
|
||
<table box="[423,903,134,368]" gridcols="4" gridrows="8" pageId="5" pageNumber="6">
|
||
<tr box="[423,903,134,151]" gridrow="0" pageId="5" pageNumber="6" rowspan-0="1">
|
||
<th box="[590,656,134,151]" gridcol="1" gridrow="0" pageId="5" pageNumber="6">
|
||
<emphasis bold="true" box="[590,656,134,151]" pageId="5" pageNumber="6">HL (cm)</emphasis>
|
||
</th>
|
||
<th box="[689,762,134,151]" gridcol="2" gridrow="0" pageId="5" pageNumber="6">
|
||
<emphasis bold="true" box="[689,762,134,151]" pageId="5" pageNumber="6">HW (cm)</emphasis>
|
||
</th>
|
||
<th box="[795,903,134,151]" gridcol="3" gridrow="0" pageId="5" pageNumber="6">
|
||
<emphasis bold="true" box="[795,896,134,151]" pageId="5" pageNumber="6">BF range (N)</emphasis>
|
||
</th>
|
||
</tr>
|
||
<tr box="[423,903,165,182]" gridrow="1" pageId="5" pageNumber="6">
|
||
<th box="[423,544,165,182]" gridcol="0" gridrow="1" pageId="5" pageNumber="6">
|
||
<materialsCitation ID-GBIF-Occurrence="2598005768" box="[423,544,165,182]" collectionCode="FMNH" pageId="5" pageNumber="6" specimenCode="FMNH PR2081">FMNH PR 2081</materialsCitation>
|
||
</th>
|
||
<td box="[590,656,165,182]" gridcol="1" gridrow="1" pageId="5" pageNumber="6">127.5</td>
|
||
<td box="[689,762,165,182]" gridcol="2" gridrow="1" pageId="5" pageNumber="6">90.2</td>
|
||
<td box="[795,903,165,182]" gridcol="3" gridrow="1" pageId="5" pageNumber="6">17,769–34,522</td>
|
||
</tr>
|
||
<tr box="[423,903,196,213]" gridrow="2" pageId="5" pageNumber="6">
|
||
<th box="[423,544,196,213]" gridcol="0" gridrow="2" pageId="5" pageNumber="6">
|
||
<materialsCitation ID-GBIF-Occurrence="2598005766" box="[423,524,196,213]" collectionCode="LACM" pageId="5" pageNumber="6" specimenCode="LACM 23844">LACM 23844</materialsCitation>
|
||
</th>
|
||
<td box="[590,656,196,213]" gridcol="1" gridrow="2" pageId="5" pageNumber="6">136.5</td>
|
||
<td box="[689,762,196,213]" gridcol="2" gridrow="2" pageId="5" pageNumber="6">89.0</td>
|
||
<td box="[795,903,196,213]" gridcol="3" gridrow="2" pageId="5" pageNumber="6">16,352–31,284</td>
|
||
</tr>
|
||
<tr box="[423,903,227,244]" gridrow="3" pageId="5" pageNumber="6">
|
||
<th box="[423,544,227,244]" gridcol="0" gridrow="3" pageId="5" pageNumber="6">
|
||
<materialsCitation ID-GBIF-Occurrence="2598005773" box="[423,496,227,244]" collectionCode="MOR" pageId="5" pageNumber="6" specimenCode="MOR 980">MOR 980</materialsCitation>
|
||
</th>
|
||
<td box="[590,656,227,244]" gridcol="1" gridrow="3" pageId="5" pageNumber="6">128.2</td>
|
||
<td box="[689,762,227,244]" gridcol="2" gridrow="3" pageId="5" pageNumber="6">81.5</td>
|
||
<td box="[795,903,227,244]" gridcol="3" gridrow="3" pageId="5" pageNumber="6">14,201–30,487</td>
|
||
</tr>
|
||
<tr box="[423,903,258,275]" gridrow="4" pageId="5" pageNumber="6">
|
||
<th box="[423,544,258,275]" gridcol="0" gridrow="4" pageId="5" pageNumber="6">
|
||
<materialsCitation ID-GBIF-Occurrence="2598005760" box="[423,496,258,275]" collectionCode="MOR" pageId="5" pageNumber="6" specimenCode="MOR 008">MOR 008</materialsCitation>
|
||
</th>
|
||
<td box="[590,656,258,275]" gridcol="1" gridrow="4" pageId="5" pageNumber="6">116.2</td>
|
||
<td box="[689,762,258,275]" gridcol="2" gridrow="4" pageId="5" pageNumber="6">79.6</td>
|
||
<td box="[795,903,258,275]" gridcol="3" gridrow="4" pageId="5" pageNumber="6">13,736–28,101</td>
|
||
</tr>
|
||
<tr box="[423,903,289,306]" gridrow="5" pageId="5" pageNumber="6">
|
||
<th box="[423,544,289,306]" gridcol="0" gridrow="5" pageId="5" pageNumber="6">
|
||
<materialsCitation ID-GBIF-Occurrence="2598005769" box="[423,495,289,306]" collectionCode="BHI" pageId="5" pageNumber="6" specimenCode="BHI 3033">BHI 3033</materialsCitation>
|
||
</th>
|
||
<td box="[590,656,289,306]" gridcol="1" gridrow="5" pageId="5" pageNumber="6">126.5</td>
|
||
<td box="[689,762,289,306]" gridcol="2" gridrow="5" pageId="5" pageNumber="6">77.2</td>
|
||
<td box="[795,903,289,306]" gridcol="3" gridrow="5" pageId="5" pageNumber="6">12,509–24,272</td>
|
||
</tr>
|
||
<tr box="[423,903,320,337]" gridrow="6" pageId="5" pageNumber="6">
|
||
<th box="[423,544,320,337]" gridcol="0" gridrow="6" pageId="5" pageNumber="6">
|
||
<materialsCitation ID-GBIF-Occurrence="2598005791" box="[423,521,320,337]" collectionCode="RTMP" pageId="5" pageNumber="6" specimenCode="RTMP 81.6.1">RTMP 81.6.1</materialsCitation>
|
||
</th>
|
||
<td box="[590,656,320,337]" gridcol="1" gridrow="6" pageId="5" pageNumber="6">117.2</td>
|
||
<td box="[689,762,320,337]" gridcol="2" gridrow="6" pageId="5" pageNumber="6">70.5</td>
|
||
<td box="[795,903,320,337]" gridcol="3" gridrow="6" pageId="5" pageNumber="6">12,197–21,799</td>
|
||
</tr>
|
||
<tr box="[423,903,351,368]" gridrow="7" pageId="5" pageNumber="6">
|
||
<th box="[423,544,351,368]" gridcol="0" gridrow="7" pageId="5" pageNumber="6">
|
||
<materialsCitation ID-GBIF-Occurrence="2598005771" box="[423,495,351,368]" collectionCode="BHI" pageId="5" pageNumber="6" specimenCode="BHI 4100">BHI 4100</materialsCitation>
|
||
</th>
|
||
<td box="[590,656,351,368]" gridcol="1" gridrow="7" pageId="5" pageNumber="6">111.5</td>
|
||
<td box="[689,762,351,368]" gridcol="2" gridrow="7" pageId="5" pageNumber="6">59.2</td>
|
||
<td box="[795,903,351,368]" gridcol="3" gridrow="7" pageId="5" pageNumber="6">8,526–18,014</td>
|
||
</tr>
|
||
</table>
|
||
</paragraph>
|
||
<caption ID-Table-UUID="DF206665055ED610FE77FE262F37FE08" httpUri="http://table.plazi.org/id/DF206665055ED610FE77FE262F37FE08" pageId="5" pageNumber="6" startId="5.[415,469,401,422]" subCaptionStartIDs="5.[980,1113,454,476]" subCaptionStarts="abbr" targetBox="[423,903,134,368]" targetIsTable="true" targetPageId="5">
|
||
<paragraph blockId="5.[415,1447,398,476]" pageId="5" pageNumber="6">
|
||
<emphasis bold="true" box="[415,493,401,422]" pageId="5" pageNumber="6">Table 1.</emphasis>
|
||
Adult
|
||
<bibRefCitation author="Carr, T. & Williamson, T. E." box="[558,573,398,412]" journalOrPublisher="Zool. J. Linn. Soc." pageId="5" pageNumber="6" pagination="479 - 523" part="142" refId="ref9512" refString="52. Carr, T. & Williamson, T. E. Diversity of late Maastrichtian Tyrannosauridae (Dinosauria: Theropoda) from western North America. Zool. J. Linn. Soc. 142, 479 - 523, doi: 10.1111 / j. 1096 - 3642.2004.00130. x (2004)." title="Diversity of late Maastrichtian Tyrannosauridae (Dinosauria: Theropoda) from western North America" type="journal article" year="2004">
|
||
<superScript attach="left" box="[558,573,398,412]" fontSize="6" pageId="5" pageNumber="6">52</superScript>
|
||
</bibRefCitation>
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[578,754,402,423]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="5" pageNumber="6" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[578,754,402,423]" italics="true" pageId="5" pageNumber="6">Tyrannosaurus rex</emphasis>
|
||
</taxonomicName>
|
||
specimens, head lengths (HL), head widths (HW), and bite forces (BF, in newtons [N]) estimated in this study (see Methods and Supplementary Table S2 for measurement details and forces at specific tooth positions; see main text for museum abbreviations).
|
||
</paragraph>
|
||
</caption>
|
||
<paragraph blockId="5.[415,1481,540,1176]" pageId="5" pageNumber="6">
|
||
The collective results of this taxon’s biomechanical and physiological feeding capacities allowed these large-bodied theropods to uniquely exploit large bones from dinosaur carcasses—known to include giant horned-dinosaurs (e.g.,
|
||
<taxonomicName authorityName="Marsh" authorityYear="1889" box="[647,751,995,1016]" class="Reptilia" family="Ceratopsidae" genus="Triceratops" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="5" pageNumber="6" phylum="Chordata" rank="genus">
|
||
<emphasis box="[647,751,995,1016]" italics="true" pageId="5" pageNumber="6">Triceratops</emphasis>
|
||
</taxonomicName>
|
||
<superScript attach="right" box="[752,789,990,1005]" fontSize="6" pageId="5" pageNumber="6">
|
||
<bibRefCitation author="Erickson, G. M. & Olson, K. H." box="[752,767,990,1004]" journalOrPublisher="J. Vert. Paleo" pageId="5" pageNumber="6" pagination="175 - 178" part="16" refId="ref7843" refString="17. Erickson, G. M. & Olson, K. H. Bite marks attributable to Tyrannosaurus rex: preliminary description and implications. J. Vert. Paleo 16, 175 - 178, doi: 10.1080 / 02724634.1996.10011297 (1996)." title="Bite marks attributable to Tyrannosaurus rex: preliminary description and implications" type="journal article" year="1996">17</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Happ, J. W." box="[774,789,990,1004]" journalOrPublisher="J. Vert. Paleo. Suppl." pageId="5" pageNumber="6" pagination="59 A" part="23" publicationUrl="http://www.jstor.org/stable/4524374" refId="ref7890" refString="18. Happ, J. W. Periosteal reaction to injuries of the supraorbital horn and squamosal of an adult Triceratops (Dinosauria: Ceratopsidae). J. Vert. Paleo. Suppl. 3 23, 59 A stable URL: http: // www. jstor. org / stable / 4524374 (2003)." title="Periosteal reaction to injuries of the supraorbital horn and squamosal of an adult Triceratops (Dinosauria: Ceratopsidae)" type="journal article" year="2003">18</bibRefCitation>
|
||
</superScript>
|
||
), duck-billed hadrosaurids (e.g.,
|
||
<taxonomicName authorityName="Lambe" authorityYear="1917" box="[1109,1258,994,1015]" class="Reptilia" family="Hadrosauridae" genus="Edmontosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="5" pageNumber="6" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1109,1258,994,1015]" italics="true" pageId="5" pageNumber="6">Edmontosaurus</emphasis>
|
||
</taxonomicName>
|
||
<superScript attach="left" box="[1258,1296,990,1005]" fontSize="6" pageId="5" pageNumber="6">
|
||
<bibRefCitation author="DePalma, R. A. II. & Burnham, D. A. & Martin, L. D. & Rothschild, B. M. & Larson, P. L." box="[1258,1273,990,1004]" journalOrPublisher="Proc. Nat. Acad. Sci. USA" pageId="5" pageNumber="6" pagination="12560 - 12564" part="110" refId="ref7711" refString="15. DePalma, R. A. II., Burnham, D. A., Martin, L. D., Rothschild, B. M. & Larson, P. L. Physical evidence of predatory behavior in Tyrannosaurus rex. Proc. Nat. Acad. Sci. USA 110, 12560 - 12564, doi: 10.1073 / pnas. 1216534110 (2013)." title="Physical evidence of predatory behavior in Tyrannosaurus rex" type="journal article" year="2013">15</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Carpenter, K." box="[1281,1296,990,1004]" editor="Perez-Moreno, B. P. & Holtz, T. J & Sanz, J. L. & Mortalla, J." journalOrPublisher="Gaia: Revista de Geosciencias, Museu Nacional de Historia Natural" pageId="5" pageNumber="6" pagination="135 - 144" refId="ref7950" refString="19. Carpenter, K. Evidence of predatory behavior by carnivorous dinosaurs in Aspects of Theropod Paleobiology (eds Perez-Moreno, B. P., Holtz, T. J., Sanz, J. L. & Mortalla, J.) 135 - 144 (Gaia: Revista de Geosciencias, Museu Nacional de Historia Natural 1998)." title="Evidence of predatory behavior by carnivorous dinosaurs in Aspects of Theropod Paleobiology" type="book chapter" year="1998">19</bibRefCitation>
|
||
</superScript>
|
||
) and even other
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="5" pageNumber="6" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1459,1473,995,1016]" italics="true" pageId="5" pageNumber="6">T</emphasis>
|
||
.
|
||
<emphasis box="[415,444,1021,1042]" italics="true" pageId="5" pageNumber="6">rex</emphasis>
|
||
</taxonomicName>
|
||
<bibRefCitation author="Longrich, N. R. & Horner, J. R. & Erickson, G. M. & Currie, P. J." box="[444,459,1017,1031]" journalOrPublisher="PLoS ONE" pageId="5" pageNumber="6" pagination="e 13419" part="5" refId="ref8014" refString="20. Longrich, N. R., Horner, J. R., Erickson, G. M. & Currie, P. J. Cannibalism in Tyrannosaurus rex. PLoS ONE 5, e 13419, doi: 10.1371 / journal. pone. 0013419 (2010)." title="Cannibalism in Tyrannosaurus rex" type="journal article" year="2010">
|
||
<superScript attach="left" box="[444,459,1017,1031]" fontSize="6" pageId="5" pageNumber="6">20</superScript>
|
||
</bibRefCitation>
|
||
—that could not be consumed otherwise by contemporary carnivores.
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[1121,1295,1021,1042]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="5" pageNumber="6" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1121,1295,1021,1042]" italics="true" pageId="5" pageNumber="6">Tyrannosaurus rex</emphasis>
|
||
</taxonomicName>
|
||
, therefore, was able to derive sustenance from bones of prey
|
||
<bibRefCitation author="DePalma, R. A. II. & Burnham, D. A. & Martin, L. D. & Rothschild, B. M. & Larson, P. L." box="[792,807,1044,1058]" journalOrPublisher="Proc. Nat. Acad. Sci. USA" pageId="5" pageNumber="6" pagination="12560 - 12564" part="110" refId="ref7711" refString="15. DePalma, R. A. II., Burnham, D. A., Martin, L. D., Rothschild, B. M. & Larson, P. L. Physical evidence of predatory behavior in Tyrannosaurus rex. Proc. Nat. Acad. Sci. USA 110, 12560 - 12564, doi: 10.1073 / pnas. 1216534110 (2013)." title="Physical evidence of predatory behavior in Tyrannosaurus rex" type="journal article" year="2013">
|
||
<superScript attach="left" box="[792,807,1044,1058]" fontSize="6" pageId="5" pageNumber="6">15</superScript>
|
||
</bibRefCitation>
|
||
and scavenged carcasses
|
||
<bibRefCitation author="Erickson, G. M." box="[1041,1056,1044,1058]" journalOrPublisher="Sci. Am." pageId="5" pageNumber="6" pagination="38 - 45" part="23" refId="ref8348" refString="27. Erickson, G. M. Breathing life into T. rex. Sci. Am. 23, 38 - 45, doi: 10.1038 / scientificamericandinosaurs 0514 - 38 (2014)." title="Breathing life into T. rex" type="journal article" year="2014">
|
||
<superScript attach="left" box="[1041,1056,1044,1058]" fontSize="6" pageId="5" pageNumber="6">27</superScript>
|
||
</bibRefCitation>
|
||
, much like extant grey wolves
|
||
<superScript attach="left" box="[1340,1362,1044,1058]" fontSize="6" pageId="5" pageNumber="6">
|
||
<bibRefCitation author="Biknevicius, A. R. & Ruff, C. B." box="[1340,1347,1044,1058]" journalOrPublisher="J. Zool" pageId="5" pageNumber="6" pagination="479 - 507" part="228" refId="ref7061" refString="1. Biknevicius, A. R. & Ruff, C. B. The structure of the mandibular corpus and its relationship to feeding behaviours in extant carnivorans. J. Zool 228, 479 - 507, doi: 10.1111 / j. 1469 - 7998.1992. tb 04450. x (1992)." title="The structure of the mandibular corpus and its relationship to feeding behaviours in extant carnivorans" type="journal article" year="1992">1</bibRefCitation>
|
||
–
|
||
<bibRefCitation author="Hill, A. P." box="[1355,1362,1044,1058]" editor="Behrensmeyer, A. K. & Hill, A. P." journalOrPublisher="Univ. Chicago Press" pageId="5" pageNumber="6" pagination="131 - 152" refId="ref7159" refString="3. Hill, A. P. Early postmortem damage to the remains of some contemporary East African mammals in Fossils in the Making: Vertebrate Taphonomy and Paleoecology (eds Behrensmeyer, A. K. & Hill, A. P.) 131 - 152 (Univ. Chicago Press 1980)." title="Early postmortem damage to the remains of some contemporary East African mammals in Fossils in the Making: Vertebrate Taphonomy and Paleoecology" type="book chapter" year="1980">3</bibRefCitation>
|
||
</superScript>
|
||
and spotted hyenas
|
||
<superScript attach="left" box="[481,524,1070,1085]" fontSize="6" pageId="5" pageNumber="6">
|
||
<bibRefCitation author="Biknevicius, A. R. & Ruff, C. B." box="[481,488,1070,1084]" journalOrPublisher="J. Zool" pageId="5" pageNumber="6" pagination="479 - 507" part="228" refId="ref7061" refString="1. Biknevicius, A. R. & Ruff, C. B. The structure of the mandibular corpus and its relationship to feeding behaviours in extant carnivorans. J. Zool 228, 479 - 507, doi: 10.1111 / j. 1469 - 7998.1992. tb 04450. x (1992)." title="The structure of the mandibular corpus and its relationship to feeding behaviours in extant carnivorans" type="journal article" year="1992">1</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Hill, A. P." box="[495,502,1070,1084]" editor="Behrensmeyer, A. K. & Hill, A. P." journalOrPublisher="Univ. Chicago Press" pageId="5" pageNumber="6" pagination="131 - 152" refId="ref7159" refString="3. Hill, A. P. Early postmortem damage to the remains of some contemporary East African mammals in Fossils in the Making: Vertebrate Taphonomy and Paleoecology (eds Behrensmeyer, A. K. & Hill, A. P.) 131 - 152 (Univ. Chicago Press 1980)." title="Early postmortem damage to the remains of some contemporary East African mammals in Fossils in the Making: Vertebrate Taphonomy and Paleoecology" type="book chapter" year="1980">3</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Binder, W. J. & Van Valkenburgh, B." box="[509,524,1070,1084]" journalOrPublisher="J. Zool. Lond." pageId="5" pageNumber="6" pagination="273 - 283" part="252" refId="ref9326" refString="48. Binder, W. J. & Van Valkenburgh, B. Development of bite strength and feeding behavior in juvenile spotted hyenas (Crocuta crocuta). J. Zool. Lond. 252, 273 - 283, doi: 10.1111 / j. 1469 - 7998.2000. tb 00622. x (2000)." title="Development of bite strength and feeding behavior in juvenile spotted hyenas (Crocuta crocuta)" type="journal article" year="2000">48</bibRefCitation>
|
||
</superScript>
|
||
. Overall, our study shows how meaningful understanding of unusual behaviours and physical capacities not seen together in living animals can be determined through multifaceted, cross-disciplinary approaches. This research adds to a growing body of literature
|
||
<superScript attach="left" box="[882,920,1124,1138]" fontSize="6" pageId="5" pageNumber="6">
|
||
<bibRefCitation author="O'Connor, P. M." box="[882,897,1124,1138]" journalOrPublisher="Nature" pageId="5" pageNumber="6" pagination="748 - 751" part="446" refId="ref9386" refString="49. O'Connor, P. M. et al. The evolution of mammal-like crocodyliforms in the Cretaceous period of Gondwana. Nature 446, 748 - 751, doi: 10.1038 / nature 09061 (2010)." title="The evolution of mammal-like crocodyliforms in the Cretaceous period of Gondwana" type="journal article" year="2010">49</bibRefCitation>
|
||
–
|
||
<bibRefCitation author="Erickson, G. M." box="[905,920,1124,1138]" journalOrPublisher="Sci. Adv." pageId="5" pageNumber="6" pagination="e 1500055 - e 1500055" part="1" refId="ref9465" refString="51. Erickson, G. M. et al. Wear biomechanics in the slicing dentition of the giant horned dinosaurs Triceratops. Sci. Adv. 1, e 1500055 - e 1500055, doi: 10.1126 / sciadv. 1500055 (2015)." title="Wear biomechanics in the slicing dentition of the giant horned dinosaurs Triceratops" type="journal article" year="2015">51</bibRefCitation>
|
||
</superScript>
|
||
that illustrates how sophisticated feeding capacities—analogous to those of modern mammals and their immediate ancestors—were first achieved in Mesozoic archosaurs.
|
||
</paragraph>
|
||
<paragraph blockId="5.[415,1480,1208,1581]" box="[415,527,1208,1234]" pageId="5" pageNumber="6">
|
||
<heading bold="true" box="[415,527,1208,1234]" fontSize="11" level="1" pageId="5" pageNumber="6" reason="0">
|
||
<emphasis bold="true" box="[415,527,1208,1234]" pageId="5" pageNumber="6">Methods</emphasis>
|
||
</heading>
|
||
</paragraph>
|
||
<paragraph blockId="5.[415,1480,1208,1581]" pageId="5" pageNumber="6">
|
||
<emphasis bold="true" box="[415,690,1236,1260]" pageId="5" pageNumber="6">Specimen Examination.</emphasis>
|
||
We examined fossil specimens, high-resolution museum-grade casts, computed tomography (CT) data, and professional photographs of the skulls, jaws, and dentitions of seven adult
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[1425,1479,1267,1288]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="5" pageNumber="6" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1425,1479,1267,1288]" italics="true" pageId="5" pageNumber="6">T. rex</emphasis>
|
||
</taxonomicName>
|
||
specimens (
|
||
<materialsCitation ID-GBIF-Occurrence="2598005763" box="[525,618,1293,1314]" collectionCode="BHI" pageId="5" pageNumber="6" specimenCode="BHI 3033">BHI 3033</materialsCitation>
|
||
[skull, cast, and CT],
|
||
<materialsCitation ID-GBIF-Occurrence="2598005782" box="[821,912,1293,1314]" collectionCode="BHI" pageId="5" pageNumber="6" specimenCode="BHI 4100">BHI 4100</materialsCitation>
|
||
[skull and cast],
|
||
<materialsCitation ID-GBIF-Occurrence="2598005772" box="[1068,1222,1293,1314]" collectionCode="FMNH" pageId="5" pageNumber="6" specimenCode="FMNH PR2081">FMNH PR 2081</materialsCitation>
|
||
[cast],
|
||
<materialsCitation ID-GBIF-Occurrence="2598005784" box="[1289,1416,1293,1314]" collectionCode="LACM" pageId="5" pageNumber="6" specimenCode="LACM 23844">LACM 23844</materialsCitation>
|
||
[cast],
|
||
<materialsCitation ID-GBIF-Occurrence="2598005770" box="[415,511,1319,1340]" collectionCode="MOR" pageId="5" pageNumber="6" specimenCode="MOR 008">MOR 008</materialsCitation>
|
||
[cast],
|
||
<materialsCitation ID-GBIF-Occurrence="2598005789" box="[583,679,1319,1340]" collectionCode="MOR" pageId="5" pageNumber="6" specimenCode="MOR 980">MOR 980</materialsCitation>
|
||
[cast],
|
||
<materialsCitation ID-GBIF-Occurrence="2598005787" box="[752,881,1319,1341]" collectionCode="RTMP" pageId="5" pageNumber="6" specimenCode="RTMP 81.6.1">RTMP 81.6.1</materialsCitation>
|
||
[skull and cast] at the AMNH and BHI). Adulthood in these individuals is based on corroborating information from craniofacial osteology
|
||
<bibRefCitation author="Carr, T. & Williamson, T. E." box="[1183,1198,1342,1356]" journalOrPublisher="Zool. J. Linn. Soc." pageId="5" pageNumber="6" pagination="479 - 523" part="142" refId="ref9512" refString="52. Carr, T. & Williamson, T. E. Diversity of late Maastrichtian Tyrannosauridae (Dinosauria: Theropoda) from western North America. Zool. J. Linn. Soc. 142, 479 - 523, doi: 10.1111 / j. 1096 - 3642.2004.00130. x (2004)." title="Diversity of late Maastrichtian Tyrannosauridae (Dinosauria: Theropoda) from western North America" type="journal article" year="2004">
|
||
<superScript attach="right" box="[1183,1198,1342,1356]" fontSize="6" pageId="5" pageNumber="6">52</superScript>
|
||
</bibRefCitation>
|
||
, overall size, and a mass-age growth curve
|
||
<bibRefCitation author="Erickson, G. M." box="[543,558,1369,1383]" journalOrPublisher="Nature" pageId="5" pageNumber="6" pagination="772 - 775" part="430" refId="ref9289" refString="47. Erickson, G. M. et al. Gigantism and comparative life-history parameters of tyrannosaurid dinosaurs. Nature 430, 772 - 775, doi: 10.1038 / nature 02699 (2004)." title="Gigantism and comparative life-history parameters of tyrannosaurid dinosaurs" type="journal article" year="2004">
|
||
<superScript attach="left" box="[543,558,1369,1383]" fontSize="6" pageId="5" pageNumber="6">47</superScript>
|
||
</bibRefCitation>
|
||
. We documented variation in head size using measures (linear distance to the nearest millimetre [mm; here and throughout our protocol]) of head width across the quadrates and head length from the anterior surface of the premaxillae to the posterior superior margin of the parietal bones. Individual variation in the lever mechanics of each skull was accounted for by measuring the linear distances between the quadrate-articular joint, and (1) the anteroposterior midpoint for osteological correlates of each jaw adductor muscle insertion along the lower jaw (i.e., “anatomical in-levers,”
|
||
<emphasis box="[777,828,1507,1528]" italics="true" pageId="5" pageNumber="6">sensu</emphasis>
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[828,843,1502,1516]" journalOrPublisher="J. Zool." pageId="5" pageNumber="6" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[828,843,1502,1516]" fontSize="6" pageId="5" pageNumber="6">35</superScript>
|
||
</bibRefCitation>
|
||
); and (2) the midpoints for the first premaxillary alveolus (P1), the third, fourth, and fifth maxillary alveoli (M3, M4, M5, respectively), and the most distal maxillary alveolus (variably M11 or M12) on the left and right sides of the skulls (out-levers).
|
||
</paragraph>
|
||
<paragraph blockId="5.[415,1479,1615,1933]" pageId="5" pageNumber="6">
|
||
<emphasis bold="true" box="[415,880,1615,1639]" pageId="5" pageNumber="6">Characterization of Tooth Contact Areas.</emphasis>
|
||
Moulds were made of M3, M4, and M5 using fast-set silicon moulding putty (Knead-a-Mold°, Townsend Atelier, Chattanooga, TN, USA) on the right and left sides of all specimens for which teeth were fully erupted (the right M5 of
|
||
<materialsCitation ID-GBIF-Occurrence="2598005780" box="[1010,1102,1671,1693]" collectionCode="BHI" pageId="5" pageNumber="6" specimenCode="BHI 4100">BHI 4100</materialsCitation>
|
||
and left M4 of
|
||
<materialsCitation ID-GBIF-Occurrence="2598005774" box="[1248,1342,1671,1692]" collectionCode="MOR" pageId="5" pageNumber="6" specimenCode="MOR 980">MOR 980</materialsCitation>
|
||
were not fully erupted and not used). These tooth crowns are the longest in the
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[1041,1095,1698,1720]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="5" pageNumber="6" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1041,1055,1699,1720]" italics="true" pageId="5" pageNumber="6">T</emphasis>
|
||
.
|
||
<emphasis box="[1066,1095,1699,1720]" italics="true" pageId="5" pageNumber="6">rex</emphasis>
|
||
</taxonomicName>
|
||
jaw and would, therefore, be the first to engage tissues in isolation during biting (and were determined to be responsible for the bite marks modelled previously
|
||
<superScript attach="left" box="[516,554,1748,1762]" fontSize="6" pageId="5" pageNumber="6">
|
||
<bibRefCitation author="Erickson, G. M. & Olson, K. H." box="[516,531,1748,1762]" journalOrPublisher="J. Vert. Paleo" pageId="5" pageNumber="6" pagination="175 - 178" part="16" refId="ref7843" refString="17. Erickson, G. M. & Olson, K. H. Bite marks attributable to Tyrannosaurus rex: preliminary description and implications. J. Vert. Paleo 16, 175 - 178, doi: 10.1080 / 02724634.1996.10011297 (1996)." title="Bite marks attributable to Tyrannosaurus rex: preliminary description and implications" type="journal article" year="1996">17</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Erickson, G. M." box="[539,554,1748,1762]" journalOrPublisher="Nature" pageId="5" pageNumber="6" pagination="706 - 708" part="382" refId="ref8268" refString="25. Erickson, G. M. et al. Bite-force estimation for Tyrannosaurus rex from tooth-marked bones. Nature 382, 706 - 708, doi: 10.1038 / 382706 a 0 (1996)." title="Bite-force estimation for Tyrannosaurus rex from tooth-marked bones" type="journal article" year="1996">25</bibRefCitation>
|
||
</superScript>
|
||
). When present, M5 is typically the longest although either M3 or M4 may act to initiate tooth indentation when M5 is missing, broken, or beginning to erupt.
|
||
</paragraph>
|
||
<paragraph blockId="5.[415,1479,1615,1933]" lastBlockId="6.[415,1480,136,185]" lastPageId="6" lastPageNumber="7" pageId="5" pageNumber="6">
|
||
High-resolution epoxy replicas of the teeth were then made (Epoxyset #145–20005, Allied High Tech Products, Inc., Rancho Dominguez, California, USA). Crown heights and cross-sectional areas along each cast from the tooth apex towards the root of the crown were measured following
|
||
<superScript attach="left" box="[1143,1173,1854,1869]" fontSize="6" pageId="5" pageNumber="6">
|
||
<bibRefCitation author="Erickson, G. M." box="[1143,1150,1854,1868]" journalOrPublisher="PLoS ONE" pageId="5" pageNumber="6" pagination="e 31781" part="7" refId="ref7358" refString="8. Erickson, G. M. et al. Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation. PLoS ONE 7, e 31781, doi: 10.1371 / journal. pone. 0031781 (2012)." title="Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation" type="journal article" year="2012">8</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1158,1173,1854,1868]" journalOrPublisher="J. Zool." pageId="5" pageNumber="6" pagination="123 - 142" part="295" refId="ref8634" refString="33. Gignac, P. M. & Erickson, G. M. Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators. J. Zool. 295, 123 - 142, doi: 10.1111 / jzo. 12187 (2015)." title="Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators" type="journal article" year="2015">33</bibRefCitation>
|
||
</superScript>
|
||
. Cross-sectional measurements of conical and lenticular tooth crowns can serve as surrogates for realized tooth contact area (as demonstrated by Gignac and Erickson
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[649,664,1908,1922]" journalOrPublisher="J. Zool." pageId="5" pageNumber="6" pagination="123 - 142" part="295" refId="ref8634" refString="33. Gignac, P. M. & Erickson, G. M. Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators. J. Zool. 295, 123 - 142, doi: 10.1111 / jzo. 12187 (2015)." title="Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators" type="journal article" year="2015">
|
||
<superScript attach="left" box="[649,664,1908,1922]" fontSize="6" pageId="5" pageNumber="6">33</superScript>
|
||
</bibRefCitation>
|
||
), which sums the total indenter surface area that is in contact with indented tissues and perpendicular to the application of bite force through the long axis of the tooth. These measurements were ultimately used for estimating pressures generated along each tooth crown (see below)
|
||
<superScript attach="none" box="[1232,1262,160,174]" fontSize="6" pageId="6" pageNumber="7">
|
||
<bibRefCitation author="Erickson, G. M." box="[1232,1239,160,174]" journalOrPublisher="PLoS ONE" pageId="6" pageNumber="7" pagination="e 31781" part="7" refId="ref7358" refString="8. Erickson, G. M. et al. Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation. PLoS ONE 7, e 31781, doi: 10.1371 / journal. pone. 0031781 (2012)." title="Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and toothpressure experimentation" type="journal article" year="2012">8</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1247,1262,160,174]" journalOrPublisher="J. Zool." pageId="6" pageNumber="7" pagination="123 - 142" part="295" refId="ref8634" refString="33. Gignac, P. M. & Erickson, G. M. Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators. J. Zool. 295, 123 - 142, doi: 10.1111 / jzo. 12187 (2015)." title="Ontogenetic changes in dental form and tooth pressures facilitate developmental niche shifts in American alligators" type="journal article" year="2015">33</bibRefCitation>
|
||
</superScript>
|
||
.
|
||
</paragraph>
|
||
<paragraph blockId="6.[415,1480,213,1439]" pageId="6" pageNumber="7">
|
||
<emphasis bold="true" box="[415,736,213,237]" pageId="6" pageNumber="7">3-D Muscle Reconstruction.</emphasis>
|
||
The actual, fully-articulated cranium, stereolithography files of individual skull bones (provided by BHI), and an articulated, high-resolution 14.45% scale replica rendered from the CT scans of
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[500,557,271,292]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="6" pageNumber="7" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[500,514,271,292]" italics="true" pageId="6" pageNumber="7">T</emphasis>
|
||
.
|
||
<emphasis box="[527,557,271,292]" italics="true" pageId="6" pageNumber="7">rex</emphasis>
|
||
</taxonomicName>
|
||
specimen
|
||
<materialsCitation ID-GBIF-Occurrence="2598005790" box="[664,760,270,292]" collectionCode="BHI" pageId="6" pageNumber="7" specimenCode="BHI 3033">BHI 3033</materialsCitation>
|
||
were examined for making adductor muscle reconstructions. To further examine the adductor chambers and relationships of muscle attachment points, a micro-CT (µCT) scan of the articulated replica was undertaken at the Microscopy and Imaging Facility of the AMNH (2010 GE phoenix v|tome|x s240 high-resolution microfocus CT system; General Electric, Fairfield, Connecticut, USA). A standard X-ray scout image was obtained prior to scanning to confirm specimen orientation and define the scan volume. The scan was performed at 170 kilovolts [kV] and 145 micro-amps [µA], using a 0.1mm copper filter, air as the background medium, and a tungsten target. The specimen was scanned at an isometric voxel size of 111.97 micrometres [µm] (= 774.88 µm at life-sized dimensions), and slices were assembled on an HP z800 workstation (Hewlett-Packard, Palo Alto, California, USA) running VG Studio Max (Volume Graphics GmbH, Heidelberg, Germany).
|
||
</paragraph>
|
||
<paragraph blockId="6.[415,1480,213,1439]" pageId="6" pageNumber="7">The specimen image stack was imported into Avizo Lite 9.0 (FEI Co., Hillsboro, Oregon, USA), where the skull and lower jaw were reconstructed separately. The lower jaw was abducted from the skull around the quadrate-articular joint to a standardized gape of 20° (measured from the anteroinferior margin of the premaxilla to the center of the quadrate-articular joint to the anterosuperior margin of the dentary). The skull and lower jaw were then resampled into one volume as a single material at an effective voxel size of 2.3513 mm (2,351.3 µm) to reduce file size and memory consumption for adductor muscle model generation as well as to scale the digital model to life-size dimensions. Although coarser, this abducted model retained bone-surface details necessary for use as an osteological scaffolding to reconstruct the jaw adductor musculature in three dimensions.</paragraph>
|
||
<paragraph blockId="6.[415,1480,213,1439]" pageId="6" pageNumber="7">
|
||
The eight adductor muscles (
|
||
<emphasis box="[719,1180,750,772]" italics="true" pageId="6" pageNumber="7">Musculus adductor mandibulae externus medialis</emphasis>
|
||
,
|
||
<emphasis italics="true" pageId="6" pageNumber="7">M. adductor mandibulae externus profundus</emphasis>
|
||
,
|
||
<emphasis box="[560,995,777,798]" italics="true" pageId="6" pageNumber="7">M. adductor mandibulae externus superficialis</emphasis>
|
||
,
|
||
<emphasis box="[1006,1327,777,798]" italics="true" pageId="6" pageNumber="7">M. adductor mandibulae posterior</emphasis>
|
||
,
|
||
<emphasis italics="true" pageId="6" pageNumber="7">M. pseudotemporalis</emphasis>
|
||
complex,
|
||
<emphasis box="[575,778,803,825]" italics="true" pageId="6" pageNumber="7">M. intramandibularis</emphasis>
|
||
,
|
||
<emphasis box="[789,1017,803,825]" italics="true" pageId="6" pageNumber="7">M. pterygoideus dorsalis</emphasis>
|
||
, and
|
||
<emphasis box="[1069,1305,803,825]" italics="true" pageId="6" pageNumber="7">M. pterygoideus ventralis</emphasis>
|
||
) that make up the archosaur jaw-closing system, based on extant
|
||
<taxonomicName box="[872,981,830,852]" class="Reptilia" kingdom="Animalia" order="Crocodylia" pageId="6" pageNumber="7" phylum="Chordata" rank="order">Crocodylia</taxonomicName>
|
||
and
|
||
<taxonomicName authorityName="Linnaeus" authorityYear="1758" box="[1029,1075,830,851]" class="Aves" kingdom="Animalia" pageId="6" pageNumber="7" phylum="Chordata" rank="class">Aves</taxonomicName>
|
||
<superScript attach="left" box="[1075,1113,826,841]" fontSize="6" pageId="6" pageNumber="7">
|
||
<bibRefCitation author="Holliday, C. M. & Witmer, L. M." box="[1075,1090,827,841]" journalOrPublisher="J. Morph" pageId="6" pageNumber="7" pagination="457 - 484" part="268" refId="ref8686" refString="34. Holliday, C. M. & Witmer, L. M. Archosaur adductor chamber evolution: integration of musculoskeletal and topological criteria in jaw muscle homology. J. Morph 268, 457 - 484, doi: 10.1002 / jmor. 10524 (2007)." title="Archosaur adductor chamber evolution: integration of musculoskeletal and topological criteria in jaw muscle homology" type="journal article" year="2007">34</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1098,1113,826,840]" journalOrPublisher="J. Zool." pageId="6" pageNumber="7" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">35</bibRefCitation>
|
||
</superScript>
|
||
, were rendered on both right and left sides (see
|
||
<figureCitation box="[509,562,857,879]" captionStart="Figure 2" captionStartId="2.[415,480,797,819]" captionTargetBox="[415,1215,124,761]" captionTargetId="figure@2.[415,1215,124,761]" captionTargetPageId="2" captionText="Figure 2. Jaw adductor muscle model for Tyrannosaurus rex (BHI 3033) in (A) dorsal, (C) left lateral, and (D) posterior views. Muscles in anatomical position are figured in (B) (lateral view is on left; anterior view is on right), textures and shades based on Alligator mississippiensis32. Abbreviations: mamem, Musculus adductor mandibulae externus medialis; mames, M. adductor mandibulae externus superficialis; mamep, M. adductor mandibulae externus profundus; mptd, M. pterygoideus dorsalis; mps, M. pseudotemporalis complex; mamp, M. adductor mandibulae posterior; mptv, M. pterygoideus ventralis; mint, M. intramandibularis." figureDoi="http://doi.org/10.5281/zenodo.3748935" httpUri="https://zenodo.org/record/3748935/files/figure.png" pageId="6" pageNumber="7">Fig. 2</figureCitation>
|
||
). Based on comparisons to gross dissections
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[982,997,853,867]" journalOrPublisher="J. Zool." pageId="6" pageNumber="7" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[982,997,853,867]" fontSize="6" pageId="6" pageNumber="7">35</superScript>
|
||
</bibRefCitation>
|
||
and diffusible iodine-based contrast-enhanced CT (diceCT) specimens
|
||
<superScript attach="right" box="[608,645,880,894]" fontSize="6" pageId="6" pageNumber="7">
|
||
<bibRefCitation author="Gignac, P. M. & Kley, N. J." box="[608,623,880,894]" journalOrPublisher="J. Exp. Zool. B (Mol. Dev. Evol)" pageId="6" pageNumber="7" pagination="166 - 176" part="322" refId="ref9569" refString="53. Gignac, P. M. & Kley, N. J. Iodine-enhanced micro-CT imaging: methodological refinements for the study of soft-tissue anatomy of post-embryonic vertebrates. J. Exp. Zool. B (Mol. Dev. Evol) 322, 166 - 176, doi: 10.1002 / jez. b. 22561 (2014)." title="Iodine-enhanced micro-CT imaging: methodological refinements for the study of soft-tissue anatomy of post-embryonic vertebrates" type="journal article" year="2014">53</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Gignac, P. M." box="[630,645,880,894]" journalOrPublisher="J. Anat." pageId="6" pageNumber="7" pagination="889 - 909" part="228" refId="ref9633" refString="54. Gignac, P. M. et al. Diffusible iodine-based contrast-enhanced computed tomography (diceCT): an emerging tool for rapid, highresolution, 3 - D imaging of metazoan soft tissues. J. Anat. 228, 889 - 909, doi: 10.1111 / joa. 12449 (2016)." title="Diffusible iodine-based contrast-enhanced computed tomography (diceCT): an emerging tool for rapid, highresolution, 3 - D imaging of metazoan soft tissues" type="journal article" year="2016">54</bibRefCitation>
|
||
</superScript>
|
||
, the adductor muscle origins and insertions listed in Holliday
|
||
<bibRefCitation author="Holliday, C. M." box="[1236,1251,880,894]" journalOrPublisher="Anat. Rec." pageId="6" pageNumber="7" pagination="1246 - 1264" part="292" refId="ref9691" refString="55. Holliday, C. M. New insights into dinosaur jaw muscle anatomy. Anat. Rec. 292, 1246 - 1264, doi: 10.1002 / ar. 20982 (2009)." title="New insights into dinosaur jaw muscle anatomy" type="journal article" year="2009">
|
||
<superScript attach="left" box="[1236,1251,880,894]" fontSize="6" pageId="6" pageNumber="7">55</superScript>
|
||
</bibRefCitation>
|
||
(see Table 4 and in-text discussion) for the above jaw-closing muscles were regionalized in
|
||
<materialsCitation ID-GBIF-Occurrence="2598005788" box="[1057,1151,910,932]" collectionCode="BHI" pageId="6" pageNumber="7" specimenCode="BHI 3033">BHI 3033</materialsCitation>
|
||
, and polygon volumes connecting those regions were rendered in Avizo Lite. Deviations in our model from the muscle attachments discussed by Holliday
|
||
<bibRefCitation author="Holliday, C. M." box="[499,514,960,974]" journalOrPublisher="Anat. Rec." pageId="6" pageNumber="7" pagination="1246 - 1264" part="292" refId="ref9691" refString="55. Holliday, C. M. New insights into dinosaur jaw muscle anatomy. Anat. Rec. 292, 1246 - 1264, doi: 10.1002 / ar. 20982 (2009)." title="New insights into dinosaur jaw muscle anatomy" type="journal article" year="2009">
|
||
<superScript attach="left" box="[499,514,960,974]" fontSize="6" pageId="6" pageNumber="7">55</superScript>
|
||
</bibRefCitation>
|
||
include the following: the two portions of
|
||
<emphasis box="[930,1129,963,985]" italics="true" pageId="6" pageNumber="7">M. pseudotemporalis</emphasis>
|
||
were represented as a single muscle belly for model simplification that originated along the anteromedial, medial, and posterior portions of the upper temporal fenestra
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[586,601,1013,1027]" journalOrPublisher="J. Zool." pageId="6" pageNumber="7" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[586,601,1013,1027]" fontSize="6" pageId="6" pageNumber="7">35</superScript>
|
||
</bibRefCitation>
|
||
, laterosphenoid
|
||
<superScript attach="left" box="[758,795,1013,1028]" fontSize="6" pageId="6" pageNumber="7">
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[758,773,1013,1027]" journalOrPublisher="J. Zool." pageId="6" pageNumber="7" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">35</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Holliday, C. M." box="[780,795,1013,1027]" journalOrPublisher="Anat. Rec." pageId="6" pageNumber="7" pagination="1246 - 1264" part="292" refId="ref9691" refString="55. Holliday, C. M. New insights into dinosaur jaw muscle anatomy. Anat. Rec. 292, 1246 - 1264, doi: 10.1002 / ar. 20982 (2009)." title="New insights into dinosaur jaw muscle anatomy" type="journal article" year="2009">55</bibRefCitation>
|
||
</superScript>
|
||
and epipterygoid
|
||
<bibRefCitation author="Holliday, C. M." box="[966,981,1013,1027]" journalOrPublisher="Anat. Rec." pageId="6" pageNumber="7" pagination="1246 - 1264" part="292" refId="ref9691" refString="55. Holliday, C. M. New insights into dinosaur jaw muscle anatomy. Anat. Rec. 292, 1246 - 1264, doi: 10.1002 / ar. 20982 (2009)." title="New insights into dinosaur jaw muscle anatomy" type="journal article" year="2009">
|
||
<superScript attach="left" box="[966,981,1013,1027]" fontSize="6" pageId="6" pageNumber="7">55</superScript>
|
||
</bibRefCitation>
|
||
;
|
||
<emphasis box="[993,1278,1017,1038]" italics="true" pageId="6" pageNumber="7">M. add. mand. ext. profundus</emphasis>
|
||
originated along the anterolateral, lateral, and posterolateral surfaces of the upper temporal fenestra; and
|
||
<emphasis box="[1215,1442,1043,1065]" italics="true" pageId="6" pageNumber="7">M. pterygoideus dorsalis</emphasis>
|
||
did not extend anteriorly past the orbits, as is the case for most birds
|
||
<bibRefCitation author="Holliday, C. M. & Witmer, L. M." box="[1045,1060,1067,1081]" journalOrPublisher="J. Morph" pageId="6" pageNumber="7" pagination="457 - 484" part="268" refId="ref8686" refString="34. Holliday, C. M. & Witmer, L. M. Archosaur adductor chamber evolution: integration of musculoskeletal and topological criteria in jaw muscle homology. J. Morph 268, 457 - 484, doi: 10.1002 / jmor. 10524 (2007)." title="Archosaur adductor chamber evolution: integration of musculoskeletal and topological criteria in jaw muscle homology" type="journal article" year="2007">
|
||
<superScript attach="left" box="[1045,1060,1067,1081]" fontSize="6" pageId="6" pageNumber="7">34</superScript>
|
||
</bibRefCitation>
|
||
but not for modern crocodylians
|
||
<superScript attach="left" box="[1386,1446,1066,1081]" fontSize="6" pageId="6" pageNumber="7">
|
||
<bibRefCitation author="Holliday, C. M. & Witmer, L. M." box="[1386,1401,1067,1081]" journalOrPublisher="J. Morph" pageId="6" pageNumber="7" pagination="457 - 484" part="268" refId="ref8686" refString="34. Holliday, C. M. & Witmer, L. M. Archosaur adductor chamber evolution: integration of musculoskeletal and topological criteria in jaw muscle homology. J. Morph 268, 457 - 484, doi: 10.1002 / jmor. 10524 (2007)." title="Archosaur adductor chamber evolution: integration of musculoskeletal and topological criteria in jaw muscle homology" type="journal article" year="2007">34</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1409,1424,1066,1080]" journalOrPublisher="J. Zool." pageId="6" pageNumber="7" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">35</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Holliday, C. M." box="[1431,1446,1066,1080]" journalOrPublisher="Anat. Rec." pageId="6" pageNumber="7" pagination="1246 - 1264" part="292" refId="ref9691" refString="55. Holliday, C. M. New insights into dinosaur jaw muscle anatomy. Anat. Rec. 292, 1246 - 1264, doi: 10.1002 / ar. 20982 (2009)." title="New insights into dinosaur jaw muscle anatomy" type="journal article" year="2009">55</bibRefCitation>
|
||
</superScript>
|
||
. In addition, the presence of a crocodylian-like, distinct
|
||
<emphasis box="[907,1107,1097,1118]" italics="true" pageId="6" pageNumber="7">M. intramandibularis</emphasis>
|
||
in
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[1136,1187,1097,1118]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="6" pageNumber="7" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1136,1187,1097,1118]" italics="true" pageId="6" pageNumber="7">T. rex</emphasis>
|
||
</taxonomicName>
|
||
is unclear because it is hypothesized to have been fused to the
|
||
<emphasis box="[725,922,1123,1145]" italics="true" pageId="6" pageNumber="7">M. pseudotemporalis</emphasis>
|
||
musculature during the evolution of Avemetatarsalia (see Holliday
|
||
<bibRefCitation author="Holliday, C. M." box="[498,513,1146,1160]" journalOrPublisher="Anat. Rec." pageId="6" pageNumber="7" pagination="1246 - 1264" part="292" refId="ref9691" refString="55. Holliday, C. M. New insights into dinosaur jaw muscle anatomy. Anat. Rec. 292, 1246 - 1264, doi: 10.1002 / ar. 20982 (2009)." title="New insights into dinosaur jaw muscle anatomy" type="journal article" year="2009">
|
||
<superScript attach="left" box="[498,513,1146,1160]" fontSize="6" pageId="6" pageNumber="7">55</superScript>
|
||
</bibRefCitation>
|
||
for a detailed assessment). In this scenario the cartilaginous sesamoid (i.e., cartilago transiliens) that joined
|
||
<emphasis box="[481,676,1177,1198]" italics="true" pageId="6" pageNumber="7">M. pseudotemporalis</emphasis>
|
||
to
|
||
<emphasis box="[706,909,1177,1198]" italics="true" pageId="6" pageNumber="7">M. intramandibularis</emphasis>
|
||
was lost, resulting in a continuous muscle belly where there had once been two. In crocodylians the cartilago transiliens leaves a shallow fossa along the superiomedial surface of the mandible, adjacent to the pterygoid flange. Particularly well-preserved
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[1166,1220,1231,1252]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="6" pageNumber="7" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1166,1220,1231,1252]" italics="true" pageId="6" pageNumber="7">T. rex</emphasis>
|
||
</taxonomicName>
|
||
specimens such as
|
||
<materialsCitation ID-GBIF-Occurrence="2598005762" collectionCode="FMNH" pageId="6" pageNumber="7" specimenCode="FMNH PR2081">FMNH PR 2081</materialsCitation>
|
||
(e.g., right mandible) may show faint evidence of such a depression (P.M.G., personal observation). Regardless, musculature attaching to the lower jaw and mandibular fossa in the position of the crocodylian
|
||
<emphasis italics="true" pageId="6" pageNumber="7">M. intramandibularis</emphasis>
|
||
and inferior avian
|
||
<emphasis box="[766,960,1310,1332]" italics="true" pageId="6" pageNumber="7">M. pseudotemporalis</emphasis>
|
||
<superScript attach="left" box="[960,997,1306,1321]" fontSize="6" pageId="6" pageNumber="7">
|
||
<bibRefCitation author="Holliday, C. M. & Witmer, L. M." box="[960,975,1307,1321]" journalOrPublisher="J. Morph" pageId="6" pageNumber="7" pagination="457 - 484" part="268" refId="ref8686" refString="34. Holliday, C. M. & Witmer, L. M. Archosaur adductor chamber evolution: integration of musculoskeletal and topological criteria in jaw muscle homology. J. Morph 268, 457 - 484, doi: 10.1002 / jmor. 10524 (2007)." title="Archosaur adductor chamber evolution: integration of musculoskeletal and topological criteria in jaw muscle homology" type="journal article" year="2007">34</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Holliday, C. M." box="[982,997,1306,1320]" journalOrPublisher="Anat. Rec." pageId="6" pageNumber="7" pagination="1246 - 1264" part="292" refId="ref9691" refString="55. Holliday, C. M. New insights into dinosaur jaw muscle anatomy. Anat. Rec. 292, 1246 - 1264, doi: 10.1002 / ar. 20982 (2009)." title="New insights into dinosaur jaw muscle anatomy" type="journal article" year="2009">55</bibRefCitation>
|
||
</superScript>
|
||
was necessary for jaw adduction. Here we retained the crocodylian muscle topology based on trace evidence of this sesamoid cartilage. Lastly,
|
||
<emphasis italics="true" pageId="6" pageNumber="7">M. pterygoideus ventralis</emphasis>
|
||
was interpreted to wrap around the posteroinferior margin of the mandible and insert along the lateral surface of the lower jaw, inferior to the dorsolateral crest of the surangular (as depicted in Fig. 7C, left of Holliday
|
||
<bibRefCitation author="Holliday, C. M." box="[1459,1474,1386,1400]" journalOrPublisher="Anat. Rec." pageId="6" pageNumber="7" pagination="1246 - 1264" part="292" refId="ref9691" refString="55. Holliday, C. M. New insights into dinosaur jaw muscle anatomy. Anat. Rec. 292, 1246 - 1264, doi: 10.1002 / ar. 20982 (2009)." title="New insights into dinosaur jaw muscle anatomy" type="journal article" year="2009">
|
||
<superScript attach="right" box="[1459,1474,1386,1400]" fontSize="6" pageId="6" pageNumber="7">55</superScript>
|
||
</bibRefCitation>
|
||
; also see
|
||
<figureCitation box="[492,564,1417,1439]" captionStart="Figure 2" captionStartId="2.[415,480,797,819]" captionTargetBox="[415,1215,124,761]" captionTargetId="figure@2.[415,1215,124,761]" captionTargetPageId="2" captionText="Figure 2. Jaw adductor muscle model for Tyrannosaurus rex (BHI 3033) in (A) dorsal, (C) left lateral, and (D) posterior views. Muscles in anatomical position are figured in (B) (lateral view is on left; anterior view is on right), textures and shades based on Alligator mississippiensis32. Abbreviations: mamem, Musculus adductor mandibulae externus medialis; mames, M. adductor mandibulae externus superficialis; mamep, M. adductor mandibulae externus profundus; mptd, M. pterygoideus dorsalis; mps, M. pseudotemporalis complex; mamp, M. adductor mandibulae posterior; mptv, M. pterygoideus ventralis; mint, M. intramandibularis." figureDoi="http://doi.org/10.5281/zenodo.3748935" httpUri="https://zenodo.org/record/3748935/files/figure.png" pageId="6" pageNumber="7">Fig. 2C</figureCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph blockId="6.[415,1480,1467,1972]" pageId="6" pageNumber="7">
|
||
<emphasis bold="true" box="[415,707,1467,1491]" pageId="6" pageNumber="7">Estimated Muscle Forces.</emphasis>
|
||
Contractile forces for each adductor muscle were derived for
|
||
<materialsCitation ID-GBIF-Occurrence="2598005786" box="[1314,1406,1470,1492]" collectionCode="BHI" pageId="6" pageNumber="7" specimenCode="BHI 3033">BHI 3033</materialsCitation>
|
||
following a validated, free-body model analogue developed by Gignac and Erickson
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1140,1155,1493,1507]" journalOrPublisher="J. Zool." pageId="6" pageNumber="7" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[1140,1155,1493,1507]" fontSize="6" pageId="6" pageNumber="7">35</superScript>
|
||
</bibRefCitation>
|
||
for
|
||
<taxonomicName baseAuthorityName="Daudin" baseAuthorityYear="1802" box="[1192,1360,1497,1519]" class="Reptilia" family="Alligatoridae" genus="Alligator" kingdom="Animalia" order="Crocodylia" pageId="6" pageNumber="7" phylum="Chordata" rank="species" species="mississippiensis">
|
||
<emphasis box="[1192,1360,1497,1519]" italics="true" pageId="6" pageNumber="7">A. mississippiensis</emphasis>
|
||
</taxonomicName>
|
||
. All muscles were assumed to have negligible pennation
|
||
<bibRefCitation author="Holliday, C. M." box="[819,834,1520,1534]" journalOrPublisher="Anat. Rec." pageId="6" pageNumber="7" pagination="1246 - 1264" part="292" refId="ref9691" refString="55. Holliday, C. M. New insights into dinosaur jaw muscle anatomy. Anat. Rec. 292, 1246 - 1264, doi: 10.1002 / ar. 20982 (2009)." title="New insights into dinosaur jaw muscle anatomy" type="journal article" year="2009">
|
||
<superScript attach="left" box="[819,834,1520,1534]" fontSize="6" pageId="6" pageNumber="7">55</superScript>
|
||
</bibRefCitation>
|
||
, following the common fascicle configurations of both crocodylian
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1464,1479,1520,1534]" journalOrPublisher="J. Zool." pageId="6" pageNumber="7" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[1464,1479,1520,1534]" fontSize="6" pageId="6" pageNumber="7">35</superScript>
|
||
</bibRefCitation>
|
||
and bird
|
||
<bibRefCitation author="Holliday, C. M. & Witmer, L. M." box="[496,511,1547,1561]" journalOrPublisher="J. Morph" pageId="6" pageNumber="7" pagination="457 - 484" part="268" refId="ref8686" refString="34. Holliday, C. M. & Witmer, L. M. Archosaur adductor chamber evolution: integration of musculoskeletal and topological criteria in jaw muscle homology. J. Morph 268, 457 - 484, doi: 10.1002 / jmor. 10524 (2007)." title="Archosaur adductor chamber evolution: integration of musculoskeletal and topological criteria in jaw muscle homology" type="journal article" year="2007">
|
||
<superScript attach="left" box="[496,511,1547,1561]" fontSize="6" pageId="6" pageNumber="7">34</superScript>
|
||
</bibRefCitation>
|
||
jaw adductor muscles. The exception to this is the uniquely pennate
|
||
<emphasis box="[1164,1185,1551,1572]" italics="true" pageId="6" pageNumber="7">M</emphasis>
|
||
.
|
||
<emphasis box="[1196,1400,1550,1571]" italics="true" pageId="6" pageNumber="7">pterygoideus ventralis</emphasis>
|
||
of crocodylians. The evolution of this muscle in eusuchians
|
||
<bibRefCitation author="Gignac, P. M. & O'Brien, H. D." box="[916,931,1573,1587]" journalOrPublisher="Integr. Comp. Biol." pageId="6" pageNumber="7" pagination="448 - 458" part="56" refId="ref9728" refString="56. Gignac, P. M. & O'Brien, H. D. Suchian feeding success at the interface of ontogeny and macroevolution. Integr. Comp. Biol. 56, 448 - 458, doi: 10.1093 / icb / icw 041 (2016)." title="Suchian feeding success at the interface of ontogeny and macroevolution" type="journal article" year="2016">
|
||
<superScript attach="left" box="[916,931,1573,1587]" fontSize="6" pageId="6" pageNumber="7">56</superScript>
|
||
</bibRefCitation>
|
||
for high bite-force generation at the expense of adductor mandibulae and temporalis musculature (e.g., primary force generators in birds and other terrestrial amniotes)
|
||
<superScript attach="none" box="[1461,1479,1600,1614]" fontSize="6" pageId="6" pageNumber="7">
|
||
<bibRefCitation author="Holliday, C. M. & Witmer, L. M." box="[1461,1476,1600,1614]" journalOrPublisher="J. Morph" pageId="6" pageNumber="7" pagination="457 - 484" part="268" refId="ref8686" refString="34. Holliday, C. M. & Witmer, L. M. Archosaur adductor chamber evolution: integration of musculoskeletal and topological criteria in jaw muscle homology. J. Morph 268, 457 - 484, doi: 10.1002 / jmor. 10524 (2007)." title="Archosaur adductor chamber evolution: integration of musculoskeletal and topological criteria in jaw muscle homology" type="journal article" year="2007">34</bibRefCitation>
|
||
,
|
||
</superScript>
|
||
<bibRefCitation author="Holliday, C. M." box="[415,430,1627,1641]" journalOrPublisher="Anat. Rec." pageId="6" pageNumber="7" pagination="1246 - 1264" part="292" refId="ref9691" refString="55. Holliday, C. M. New insights into dinosaur jaw muscle anatomy. Anat. Rec. 292, 1246 - 1264, doi: 10.1002 / ar. 20982 (2009)." title="New insights into dinosaur jaw muscle anatomy" type="journal article" year="2009">
|
||
<superScript attach="left" box="[415,430,1627,1641]" fontSize="6" pageId="6" pageNumber="7">55</superScript>
|
||
</bibRefCitation>
|
||
promoted stealthy prey-capture behaviors at the water’s edge
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1012,1027,1627,1641]" journalOrPublisher="J. Zool." pageId="6" pageNumber="7" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[1012,1027,1627,1641]" fontSize="6" pageId="6" pageNumber="7">35</superScript>
|
||
</bibRefCitation>
|
||
. Modern crocodylians utilize this jaw adductor configuration for a substantially different feeding strategy than that inferred for
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[1162,1215,1657,1679]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="6" pageNumber="7" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1162,1176,1658,1679]" italics="true" pageId="6" pageNumber="7">T</emphasis>
|
||
.
|
||
<emphasis box="[1186,1215,1658,1679]" italics="true" pageId="6" pageNumber="7">rex</emphasis>
|
||
</taxonomicName>
|
||
. Without an
|
||
<emphasis box="[1337,1407,1658,1679]" italics="true" pageId="6" pageNumber="7">a priori</emphasis>
|
||
biological reason for assuming crocodylian-like pennation in
|
||
<emphasis box="[938,959,1684,1705]" italics="true" pageId="6" pageNumber="7">M</emphasis>
|
||
.
|
||
<emphasis box="[969,1173,1684,1705]" italics="true" pageId="6" pageNumber="7">pterygoideus ventralis</emphasis>
|
||
, we modelled this muscle with a parallel fiber arrangement in
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[692,746,1711,1732]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="6" pageNumber="7" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[692,706,1711,1732]" italics="true" pageId="6" pageNumber="7">T</emphasis>
|
||
.
|
||
<emphasis box="[717,746,1711,1732]" italics="true" pageId="6" pageNumber="7">rex</emphasis>
|
||
</taxonomicName>
|
||
.
|
||
</paragraph>
|
||
<paragraph blockId="6.[415,1480,1467,1972]" lastBlockId="7.[415,1479,136,425]" lastPageId="7" lastPageNumber="8" pageId="6" pageNumber="7">
|
||
To estimate physiological cross-sectional areas (PCSA) left- and right-side volumes for each muscle were (1) averaged, (2) divided by the density of archosaur skeletal muscle (1.056 gram [g]/cm
|
||
<superScript attach="left" box="[1224,1231,1760,1774]" fontSize="6" pageId="6" pageNumber="7">3</superScript>
|
||
)
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1239,1254,1760,1774]" journalOrPublisher="J. Zool." pageId="6" pageNumber="7" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[1239,1254,1760,1774]" fontSize="6" pageId="6" pageNumber="7">35</superScript>
|
||
</bibRefCitation>
|
||
to estimate mass of the contractile tissues, and (3) further divided by left-right average muscle lengths (see Gignac and Erickson
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1430,1445,1787,1801]" journalOrPublisher="J. Zool." pageId="6" pageNumber="7" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[1430,1445,1787,1801]" fontSize="6" pageId="6" pageNumber="7">35</superScript>
|
||
</bibRefCitation>
|
||
for protocol quantifying 3-D muscle position) (
|
||
<httpUri box="[825,1055,1817,1839]" httpUri="https://static-content.springer.com/esm/art%3A10.1038%2Fs41598-017-02161-w/MediaObjects/41598_2017_2161_MOESM1_ESM.xls" pageId="6" pageNumber="7">Supplementary Table S1</httpUri>
|
||
). As demonstrated by Gignac and Erickson
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1464,1479,1813,1827]" journalOrPublisher="J. Zool." pageId="6" pageNumber="7" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[1464,1479,1813,1827]" fontSize="6" pageId="6" pageNumber="7">35</superScript>
|
||
</bibRefCitation>
|
||
muscle length can serve as a proxy for fascicle length in parallel-fibered muscles when statically modelled. Length measurements (
|
||
<httpUri box="[569,807,1870,1892]" httpUri="https://static-content.springer.com/esm/art%3A10.1038%2Fs41598-017-02161-w/MediaObjects/41598_2017_2161_MOESM1_ESM.xls" pageId="6" pageNumber="7">Supplementary Table S1</httpUri>
|
||
) were made as the 3-D linear distance between the centroids of each muscle’s origin and insertion. Each muscle was assigned an archosaur-specific muscle stress of 32.4 N/cm
|
||
<superScript attach="left" box="[1428,1435,1894,1908]" fontSize="6" pageId="6" pageNumber="7">2</superScript>
|
||
that was empirically determined from
|
||
<taxonomicName baseAuthorityName="Daudin" baseAuthorityYear="1802" box="[734,903,1924,1945]" class="Reptilia" family="Alligatoridae" genus="Alligator" kingdom="Animalia" order="Crocodylia" pageId="6" pageNumber="7" phylum="Chordata" rank="species" species="mississippiensis">
|
||
<emphasis box="[734,750,1924,1945]" italics="true" pageId="6" pageNumber="7">A</emphasis>
|
||
.
|
||
<emphasis box="[760,903,1924,1945]" italics="true" pageId="6" pageNumber="7">mississippiensis</emphasis>
|
||
</taxonomicName>
|
||
jaw adductor musculature
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1154,1169,1920,1934]" journalOrPublisher="J. Zool." pageId="6" pageNumber="7" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[1154,1169,1920,1934]" fontSize="6" pageId="6" pageNumber="7">35</superScript>
|
||
</bibRefCitation>
|
||
. (These values are not known for jaw muscles in
|
||
<taxonomicName authorityName="Linnaeus" authorityYear="1758" box="[557,604,1950,1971]" class="Aves" kingdom="Animalia" pageId="6" pageNumber="7" phylum="Chordata" rank="class">Aves</taxonomicName>
|
||
, which also lack teeth). Muscle forces were modelled assuming a tetanic contraction of 100% (
|
||
<httpUri box="[421,653,136,158]" httpUri="https://static-content.springer.com/esm/art%3A10.1038%2Fs41598-017-02161-w/MediaObjects/41598_2017_2161_MOESM1_ESM.xls" pageId="7" pageNumber="8">Supplementary Table S1</httpUri>
|
||
), which is broadly consistent with the maximum muscle recruitment values quantified by Cleuren
|
||
<emphasis box="[524,562,163,185]" italics="true" pageId="7" pageNumber="8">et al</emphasis>
|
||
.
|
||
<bibRefCitation author="Cleuren, J. & Aerts, P. & de Vree, F." box="[568,583,160,174]" journalOrPublisher="Belg. J. Zool." pageId="7" pageNumber="8" pagination="79 - 94" part="125" refId="ref9778" refString="57. Cleuren, J., Aerts, P. & de Vree, F. Bite and joint force analysis in Caiman crocodilus. Belg. J. Zool. 125, 79 - 94 (1995)." title="Bite and joint force analysis in Caiman crocodilus" type="journal article" year="1995">
|
||
<superScript attach="left" box="[568,583,160,174]" fontSize="6" pageId="7" pageNumber="8">57</superScript>
|
||
</bibRefCitation>
|
||
for
|
||
<emphasis box="[620,793,163,185]" italics="true" pageId="7" pageNumber="8">Caiman crocodilus</emphasis>
|
||
and comparable to Gignac and Erickson
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1176,1191,160,174]" journalOrPublisher="J. Zool." pageId="7" pageNumber="8" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[1176,1191,160,174]" fontSize="6" pageId="7" pageNumber="8">35</superScript>
|
||
</bibRefCitation>
|
||
for
|
||
<taxonomicName baseAuthorityName="Daudin" baseAuthorityYear="1802" box="[1228,1397,164,185]" class="Reptilia" family="Alligatoridae" genus="Alligator" kingdom="Animalia" order="Crocodylia" pageId="7" pageNumber="8" phylum="Chordata" rank="species" species="mississippiensis">
|
||
<emphasis box="[1228,1244,164,185]" italics="true" pageId="7" pageNumber="8">A</emphasis>
|
||
.
|
||
<emphasis box="[1254,1397,164,185]" italics="true" pageId="7" pageNumber="8">mississippiensis</emphasis>
|
||
</taxonomicName>
|
||
through modelling of empirically derived bite-force values.
|
||
</paragraph>
|
||
<paragraph blockId="7.[415,1479,136,425]" pageId="7" pageNumber="8">
|
||
Jaw closure in
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[584,639,217,238]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="7" pageNumber="8" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[584,598,217,238]" italics="true" pageId="7" pageNumber="8">T</emphasis>
|
||
.
|
||
<emphasis box="[610,639,217,238]" italics="true" pageId="7" pageNumber="8">rex</emphasis>
|
||
</taxonomicName>
|
||
is orthal with bite forces acting exclusively along the vertical (i.e., Y-oriented) axis of the teeth. Therefore, the dorsad-only component of each tetanic muscle force (
|
||
<httpUri box="[1121,1353,243,265]" httpUri="https://static-content.springer.com/esm/art%3A10.1038%2Fs41598-017-02161-w/MediaObjects/41598_2017_2161_MOESM1_ESM.xls" pageId="7" pageNumber="8">Supplementary Table S1</httpUri>
|
||
) was derived to estimate muscle moments at insertion points following the iterative Pythagorean Theorem approach of Gignac and Erickson
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[541,556,293,307]" journalOrPublisher="J. Zool." pageId="7" pageNumber="8" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[541,556,293,307]" fontSize="6" pageId="7" pageNumber="8">35</superScript>
|
||
</bibRefCitation>
|
||
. This technique facilitates the ready transformation of tetanic muscle forces into muscle moments based on the anatomical in-lever lengths
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[807,822,320,334]" journalOrPublisher="J. Zool." pageId="7" pageNumber="8" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[807,822,320,334]" fontSize="6" pageId="7" pageNumber="8">35</superScript>
|
||
</bibRefCitation>
|
||
unique to each skull (
|
||
<httpUri box="[1034,1270,323,345]" httpUri="https://static-content.springer.com/esm/art%3A10.1038%2Fs41598-017-02161-w/MediaObjects/41598_2017_2161_MOESM1_ESM.xls" pageId="7" pageNumber="8">Supplementary Table S2</httpUri>
|
||
). The muscle-specific vertical components of contractile force for left and right-side jaw adductor muscle reconstructions in
|
||
<materialsCitation ID-GBIF-Occurrence="2598005758" box="[1387,1479,350,371]" collectionCode="BHI" pageId="7" pageNumber="8" specimenCode="BHI 3033">BHI 3033</materialsCitation>
|
||
were averaged (
|
||
<httpUri box="[560,789,376,398]" httpUri="https://static-content.springer.com/esm/art%3A10.1038%2Fs41598-017-02161-w/MediaObjects/41598_2017_2161_MOESM1_ESM.xls" pageId="7" pageNumber="8">Supplementary Table S1</httpUri>
|
||
) for use in estimating size-specific, Y-axis contractile muscle forces in the other adult
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[525,579,404,425]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="7" pageNumber="8" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[525,539,404,425]" italics="true" pageId="7" pageNumber="8">T</emphasis>
|
||
.
|
||
<emphasis box="[550,579,404,425]" italics="true" pageId="7" pageNumber="8">rex</emphasis>
|
||
</taxonomicName>
|
||
specimens.
|
||
</paragraph>
|
||
<paragraph blockId="7.[415,1480,456,935]" pageId="7" pageNumber="8">
|
||
<emphasis bold="true" box="[415,875,456,480]" pageId="7" pageNumber="8">Specimen Specific Bite-force Estimates.</emphasis>
|
||
We used the tetanic muscle forces derived for
|
||
<materialsCitation ID-GBIF-Occurrence="2598005752" box="[1344,1438,460,481]" collectionCode="BHI" pageId="7" pageNumber="8" specimenCode="BHI 3033">BHI 3033</materialsCitation>
|
||
and bite-force relevant anatomical differences
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[810,825,483,497]" journalOrPublisher="J. Zool." pageId="7" pageNumber="8" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[810,825,483,497]" fontSize="6" pageId="7" pageNumber="8">35</superScript>
|
||
</bibRefCitation>
|
||
across our sample of skulls as the basis for estimating bite-force performance in the six-other adult
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[711,765,513,535]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="7" pageNumber="8" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[711,725,514,535]" italics="true" pageId="7" pageNumber="8">T</emphasis>
|
||
.
|
||
<emphasis box="[736,765,514,535]" italics="true" pageId="7" pageNumber="8">rex</emphasis>
|
||
</taxonomicName>
|
||
specimens (Supplementary Table S2). Among living carnivorous archosaurs such as crocodylians, head width across the quadrates is a strong indicator of body size differences because it correlates strongly with body mass (Pearson’s product moment correlation = 0.99, n = 35)
|
||
<bibRefCitation author="Gignac, P. M. & O'Brien, H. D." box="[1226,1241,563,577]" journalOrPublisher="Integr. Comp. Biol." pageId="7" pageNumber="8" pagination="448 - 458" part="56" refId="ref9728" refString="56. Gignac, P. M. & O'Brien, H. D. Suchian feeding success at the interface of ontogeny and macroevolution. Integr. Comp. Biol. 56, 448 - 458, doi: 10.1093 / icb / icw 041 (2016)." title="Suchian feeding success at the interface of ontogeny and macroevolution" type="journal article" year="2016">
|
||
<superScript attach="none" box="[1226,1241,563,577]" fontSize="6" pageId="7" pageNumber="8">56</superScript>
|
||
</bibRefCitation>
|
||
. Therefore, we compared head width across the quadrates for our
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[803,858,593,615]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="7" pageNumber="8" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[803,817,594,615]" italics="true" pageId="7" pageNumber="8">T</emphasis>
|
||
.
|
||
<emphasis box="[829,858,594,615]" italics="true" pageId="7" pageNumber="8">rex</emphasis>
|
||
</taxonomicName>
|
||
sample and linearly scaled the
|
||
<materialsCitation ID-GBIF-Occurrence="2598005783" box="[1159,1252,593,614]" collectionCode="BHI" pageId="7" pageNumber="8" specimenCode="BHI 3033">BHI 3033</materialsCitation>
|
||
vertical components of muscle force for each jaw adductor muscle to the values appropriate for
|
||
<materialsCitation ID-GBIF-Occurrence="2598005765" box="[1083,1176,620,641]" collectionCode="BHI" pageId="7" pageNumber="8" specimenCode="BHI 4100">BHI 4100</materialsCitation>
|
||
,
|
||
<materialsCitation ID-GBIF-Occurrence="2598005775" box="[1183,1337,620,641]" collectionCode="FMNH" pageId="7" pageNumber="8" specimenCode="FMNH PR2081">FMNH PR 2081</materialsCitation>
|
||
,
|
||
<materialsCitation ID-GBIF-Occurrence="2598005776" box="[1346,1475,620,641]" collectionCode="LACM" pageId="7" pageNumber="8" specimenCode="LACM 23844">LACM 23844</materialsCitation>
|
||
,
|
||
<materialsCitation ID-GBIF-Occurrence="2598005755" box="[415,512,646,667]" collectionCode="MOR" pageId="7" pageNumber="8" specimenCode="MOR 008">MOR 008</materialsCitation>
|
||
,
|
||
<materialsCitation ID-GBIF-Occurrence="2598005756" box="[522,619,646,667]" collectionCode="MOR" pageId="7" pageNumber="8" specimenCode="MOR 980">MOR 980</materialsCitation>
|
||
, and
|
||
<materialsCitation ID-GBIF-Occurrence="2598005767" box="[671,799,646,668]" collectionCode="RTMP" pageId="7" pageNumber="8" specimenCode="RTMP 81.6.1">RTMP 81.6.1</materialsCitation>
|
||
based on these widths (
|
||
<httpUri box="[1032,1269,646,668]" httpUri="https://static-content.springer.com/esm/art%3A10.1038%2Fs41598-017-02161-w/MediaObjects/41598_2017_2161_MOESM1_ESM.xls" pageId="7" pageNumber="8">Supplementary Table S2</httpUri>
|
||
). Linear scaling (e.g., instead of a power curve) was used because the seven adult
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[969,1022,673,695]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="7" pageNumber="8" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[969,983,674,695]" italics="true" pageId="7" pageNumber="8">T</emphasis>
|
||
.
|
||
<emphasis box="[993,1022,674,695]" italics="true" pageId="7" pageNumber="8">rex</emphasis>
|
||
</taxonomicName>
|
||
specimens occupy only a 34% range of total possible ontogenetic variation in head width, and linear versus power best-fit curves of muscle forces plotted against head width are not statistically distinguishable across such relatively small spans of body size in adult individuals of living animal models with low sample size (e.g.,
|
||
<taxonomicName baseAuthorityName="Daudin" baseAuthorityYear="1802" box="[894,1065,753,775]" class="Reptilia" family="Alligatoridae" genus="Alligator" kingdom="Animalia" order="Crocodylia" pageId="7" pageNumber="8" phylum="Chordata" rank="species" species="mississippiensis">
|
||
<emphasis box="[894,910,753,774]" italics="true" pageId="7" pageNumber="8">A</emphasis>
|
||
.
|
||
<emphasis box="[921,1065,754,775]" italics="true" pageId="7" pageNumber="8">mississippiensis</emphasis>
|
||
</taxonomicName>
|
||
<bibRefCitation author="Gignac, P. M. & Erickson, G. M." box="[1064,1079,749,763]" journalOrPublisher="J. Zool." pageId="7" pageNumber="8" pagination="229 - 238" part="299" refId="ref8737" refString="35. Gignac, P. M. & Erickson, G. M. Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding. J. Zool. 299, 229 - 238, doi: 10.1111 / jzo. 12349 (2016)." title="Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding" type="journal article" year="2016">
|
||
<superScript attach="left" box="[1064,1079,749,763]" fontSize="6" pageId="7" pageNumber="8">35</superScript>
|
||
</bibRefCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph blockId="7.[415,1480,456,935]" pageId="7" pageNumber="8">
|
||
For each specimen, we then multiplied the scaled vertical component of muscle force into that muscle’s (right and left-side averaged) anatomical in-levers to produce muscle moments (
|
||
<httpUri box="[1189,1424,806,828]" httpUri="https://static-content.springer.com/esm/art%3A10.1038%2Fs41598-017-02161-w/MediaObjects/41598_2017_2161_MOESM1_ESM.xls" pageId="7" pageNumber="8">Supplementary Table S2</httpUri>
|
||
). The moments were summed, doubled (to account for the contralateral side jaw adductor musculature), and divided by each of the out-lever distances for P1, M3, M4, M5, and M11/12 tooth positions on the right and left sides to produce maximum bite-force estimations at the most mesial (P1) and distal (M11/12) tooth positions as well as for the most procumbent teeth (M3, M4, M5) (Supplementary Table S2).
|
||
</paragraph>
|
||
<paragraph blockId="7.[415,1479,966,1231]" pageId="7" pageNumber="8">
|
||
<emphasis bold="true" box="[415,607,966,990]" pageId="7" pageNumber="8">Tooth Pressures.</emphasis>
|
||
Pressures along the tooth crowns of each individual were calculated by dividing the maximum estimated individual bite force at each tooth position by the tooth’s cross-sectional area measured at 1, 7, 13, 19, 25, 31 and 37 mm from the apex (Supplementary Table S2). These distances provided for the minimum cross-sectional area that could be measured reliably (1 mm), maximum indentation depth known for an adult
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="7" pageNumber="8" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1459,1473,1050,1071]" italics="true" pageId="7" pageNumber="8">T</emphasis>
|
||
.
|
||
<emphasis box="[415,444,1077,1098]" italics="true" pageId="7" pageNumber="8">rex</emphasis>
|
||
</taxonomicName>
|
||
bite mark (~37.5mm)
|
||
<superScript attach="none" box="[660,697,1072,1087]" fontSize="6" pageId="7" pageNumber="8">
|
||
<bibRefCitation author="DePalma, R. A. II. & Burnham, D. A. & Martin, L. D. & Rothschild, B. M. & Larson, P. L." box="[660,675,1072,1086]" journalOrPublisher="Proc. Nat. Acad. Sci. USA" pageId="7" pageNumber="8" pagination="12560 - 12564" part="110" refId="ref7711" refString="15. DePalma, R. A. II., Burnham, D. A., Martin, L. D., Rothschild, B. M. & Larson, P. L. Physical evidence of predatory behavior in Tyrannosaurus rex. Proc. Nat. Acad. Sci. USA 110, 12560 - 12564, doi: 10.1073 / pnas. 1216534110 (2013)." title="Physical evidence of predatory behavior in Tyrannosaurus rex" type="journal article" year="2013">15</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Erickson, G. M. & Olson, K. H." box="[682,697,1072,1086]" journalOrPublisher="J. Vert. Paleo" pageId="7" pageNumber="8" pagination="175 - 178" part="16" refId="ref7843" refString="17. Erickson, G. M. & Olson, K. H. Bite marks attributable to Tyrannosaurus rex: preliminary description and implications. J. Vert. Paleo 16, 175 - 178, doi: 10.1080 / 02724634.1996.10011297 (1996)." title="Bite marks attributable to Tyrannosaurus rex: preliminary description and implications" type="journal article" year="1996">17</bibRefCitation>
|
||
</superScript>
|
||
, and a series of regular intervals in between. Only tooth casts of pristine (undamaged) or nearly pristine (slightly worn) teeth were used in the analysis. These values were then compared to the ultimate shear stress of cortical bone
|
||
<superScript attach="left" box="[764,794,1126,1140]" fontSize="6" pageId="7" pageNumber="8">
|
||
<bibRefCitation author="Carter, D. R. & Beaupre, G. S." bookContentInfo="318" box="[764,771,1126,1140]" journalOrPublisher="Cambridge Univ. Press" pageId="7" pageNumber="8" refId="ref7216" refString="4. Carter, D. R. & Beaupre, G. S. Skeletal Function and Form: Mechanobiology of Skeletal Development, Aging, and Regeneration 318 (Cambridge Univ. Press 2001)." title="Skeletal Function and Form: Mechanobiology of Skeletal Development, Aging, and Regeneration" type="book" year="2001">4</bibRefCitation>
|
||
,
|
||
<bibRefCitation author="Turner, C. H. & Wang, T. & Burr, D. B." box="[779,794,1126,1140]" journalOrPublisher="Calcif. Tissue Int." pageId="7" pageNumber="8" pagination="373 - 378" part="69" refId="ref8951" refString="39. Turner, C. H., Wang, T. & Burr, D. B. Shear strength and fatigue properties of human cortical bone determined from pure shear tests. Calcif. Tissue Int. 69, 373 - 378, doi: 10.1007 / s 00223 - 001 - 1006 - 1 (2001)." title="Shear strength and fatigue properties of human cortical bone determined from pure shear tests" type="journal article" year="2001">39</bibRefCitation>
|
||
</superScript>
|
||
. (Note: of the 31 tooth crowns we cast and measured, the following [see also Supplementary Table S2] were either blunted or showed fracture spalls at the crown apex and were not used in the apical tooth pressure analysis [
|
||
<materialsCitation ID-GBIF-Occurrence="2598005777" box="[757,851,1183,1204]" collectionCode="BHI" pageId="7" pageNumber="8" specimenCode="BHI 3033">BHI 3033</materialsCitation>
|
||
left M5 and right M4,
|
||
<materialsCitation ID-GBIF-Occurrence="2598005764" box="[1060,1151,1183,1204]" collectionCode="BHI" pageId="7" pageNumber="8" specimenCode="BHI 4100">BHI 4100</materialsCitation>
|
||
right M3 and M4,
|
||
<materialsCitation ID-GBIF-Occurrence="2598005785" box="[1326,1479,1183,1204]" collectionCode="FMNH" pageId="7" pageNumber="8" specimenCode="FMNH PR2081">FMNH PR 2081</materialsCitation>
|
||
left M5,
|
||
<materialsCitation ID-GBIF-Occurrence="2598005761" box="[493,587,1209,1230]" collectionCode="MOR" pageId="7" pageNumber="8" specimenCode="MOR 008">MOR 008</materialsCitation>
|
||
right M4,
|
||
<materialsCitation ID-GBIF-Occurrence="2598005757" box="[686,780,1209,1230]" collectionCode="MOR" pageId="7" pageNumber="8" specimenCode="MOR 980">MOR 980</materialsCitation>
|
||
left M5 and right M4, and
|
||
<materialsCitation ID-GBIF-Occurrence="2598005759" box="[1034,1160,1209,1231]" collectionCode="RTMP" pageId="7" pageNumber="8" specimenCode="RTMP 81.6.1">RTMP 81.6.1</materialsCitation>
|
||
left M4 and right M5]).
|
||
</paragraph>
|
||
<paragraph blockId="7.[415,1480,1262,1394]" pageId="7" pageNumber="8">
|
||
<emphasis bold="true" box="[415,952,1262,1286]" pageId="7" pageNumber="8">Tooth and Palatal Contact Characterizations.</emphasis>
|
||
The distribution and spacing of adult
|
||
<taxonomicName authorityName="Osborn" authorityYear="1905" box="[1361,1418,1266,1287]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="7" pageNumber="8" phylum="Chordata" rank="species" species="rex">
|
||
<emphasis box="[1361,1375,1266,1287]" italics="true" pageId="7" pageNumber="8">T</emphasis>
|
||
.
|
||
<emphasis box="[1388,1418,1266,1287]" italics="true" pageId="7" pageNumber="8">rex</emphasis>
|
||
</taxonomicName>
|
||
tooth crowns and palatal architecture were taken into consideration with regard to how they contributed to this animal’s ability to remove/comminute bones during biting. Specifically, we interpreted the loading of individual teeth (
|
||
<figureCitation box="[422,475,1346,1368]" captionStart="Figure 3" captionStartId="3.[415,480,1101,1123]" captionTargetBox="[415,1215,124,1066]" captionTargetId="figure@3.[415,1215,124,1066]" captionTargetPageId="3" captionText="Figure 3. Tyrannosaurus rex dental functional morphology. (A) Exemplar tooth pressures along the distal 37mm of the left M5 of BHI 3033 (warmer colours indicate higher pressures), illustrating bone-penetrating shear stresses (>65MPa4, 39) for almost 25mm of indentation depth. (B) Mesial and distal facing carinae (white arrows) helped direct pathways of bone fracture towards adjacent maxillary teeth (C) (ventral view of BHI 3033) that were also engaged during indentation, illustrating how the most procumbent maxillary tooth crowns collectively form a fracture arcade (pink arrows) due to pressures generated when biting. (Figure element in (A) derived from digital scan by Virtual Surfaces, Inc)." figureDoi="http://doi.org/10.5281/zenodo.3748937" httpUri="https://zenodo.org/record/3748937/files/figure.png" pageId="7" pageNumber="8">Fig. 3</figureCitation>
|
||
) as well as the collective damage invoked on bones by simultaneous indenting of both the upper and lower dentition in conjuction with potential palatal contacts (
|
||
<figureCitation box="[937,995,1372,1394]" captionStart="Figure 1" captionStartId="1.[415,479,639,661]" captionTargetBox="[415,1055,124,604]" captionTargetId="figure@1.[415,1055,124,604]" captionTargetPageId="1" captionText="Figure 1. Left ilium of Triceratops sp. (MOR 799) in ventrolateral view with ~80 bite marks attributed to Tyrannosaurus rex. A large portion (~17%) of the iliac crest was removed (bracketed) by repetitive, localized biting." figureDoi="http://doi.org/10.5281/zenodo.3748933" httpUri="https://zenodo.org/record/3748933/files/figure.png" pageId="7" pageNumber="8">Figs 1</figureCitation>
|
||
,
|
||
<figureCitation box="[1005,1017,1372,1393]" captionStart="Figure 3" captionStartId="3.[415,480,1101,1123]" captionTargetBox="[415,1215,124,1066]" captionTargetId="figure@3.[415,1215,124,1066]" captionTargetPageId="3" captionText="Figure 3. Tyrannosaurus rex dental functional morphology. (A) Exemplar tooth pressures along the distal 37mm of the left M5 of BHI 3033 (warmer colours indicate higher pressures), illustrating bone-penetrating shear stresses (>65MPa4, 39) for almost 25mm of indentation depth. (B) Mesial and distal facing carinae (white arrows) helped direct pathways of bone fracture towards adjacent maxillary teeth (C) (ventral view of BHI 3033) that were also engaged during indentation, illustrating how the most procumbent maxillary tooth crowns collectively form a fracture arcade (pink arrows) due to pressures generated when biting. (Figure element in (A) derived from digital scan by Virtual Surfaces, Inc)." figureDoi="http://doi.org/10.5281/zenodo.3748937" httpUri="https://zenodo.org/record/3748937/files/figure.png" pageId="7" pageNumber="8">3</figureCitation>
|
||
and
|
||
<figureCitation box="[1063,1075,1372,1393]" captionStart="Figure 4" captionStartId="4.[415,480,1406,1428]" captionTargetBox="[418,1052,127,1368]" captionTargetId="figure@4.[415,1055,124,1371]" captionTargetPageId="4" captionText="Figure 4. Jaw models of Tyrannosaurus rex paired with idealized beam diagrams, illustrating three- (A) (lateral view), (B) (anterior view) and four-point ((C), anterior view) loading configurations that allowed T. rex to promote failure stresses and fracture rigid structures (e.g., bone) without the aid of occluding dentitions. Teeth (cones) and the osseus palate, composed of the right and left maxillae and an anterior expansion of the vomer (rectangle), are shown as contact points in pink; original beam shapes are dark blue; and idealized plastic deformations (exaggerated) are light blue." figureDoi="http://doi.org/10.5281/zenodo.3748939" httpUri="https://zenodo.org/record/3748939/files/figure.png" pageId="7" pageNumber="8">4</figureCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph blockId="7.[415,1480,1425,1531]" pageId="7" pageNumber="8">
|
||
<emphasis bold="true" box="[415,507,1425,1449]" pageId="7" pageNumber="8">Figures.</emphasis>
|
||
Jaw adductor muscle figures were rendered by exporting polygon files from Avizo Lite into Meshlab version 1.3.3 (GNU General Public License version 2.0). Skull and muscle models were down-sampled in Meshlab using the Quadratic Edge Collapse Decimation tool. Colours were mapped to muscle polygons based on the phenotype of fresh adult
|
||
<taxonomicName baseAuthorityName="Daudin" baseAuthorityYear="1802" box="[617,787,1509,1530]" class="Reptilia" family="Alligatoridae" genus="Alligator" kingdom="Animalia" order="Crocodylia" pageId="7" pageNumber="8" phylum="Chordata" rank="species" species="mississippiensis">
|
||
<emphasis box="[617,787,1509,1530]" italics="true" pageId="7" pageNumber="8">A. mississippiensis</emphasis>
|
||
</taxonomicName>
|
||
jaw adductor musculature
|
||
<bibRefCitation author="Gignac, P. M." box="[1040,1055,1505,1519]" journalOrPublisher="Florida State University" pageId="7" pageNumber="8" refId="ref8589" refString="32. Gignac, P. M. Biomechanics and the ontogeny of feeding in the American alligator (Alligator mississippiensis): reconciling factors contributing to intraspecific niche differentiation in a large-bodied vertebrate. PhD thesis, Florida State University (2010)." title="Biomechanics and the ontogeny of feeding in the American alligator (Alligator mississippiensis): reconciling factors contributing to intraspecific niche differentiation in a large-bodied vertebrate" type="book" year="2010">
|
||
<superScript attach="left" box="[1040,1055,1505,1519]" fontSize="6" pageId="7" pageNumber="8">32</superScript>
|
||
</bibRefCitation>
|
||
.
|
||
</paragraph>
|
||
</subSubSection>
|
||
</treatment>
|
||
</document> |