500 lines
94 KiB
XML
500 lines
94 KiB
XML
<document id="58C5D81AE098FD4C7B277C41E79692AE" ID-CLB-Dataset="21496" ID-DOI="10.5281/zenodo.3943260" ID-GBIF-Dataset="3e00ef13-3995-4f38-b69b-6df75b6ee2e5" ID-Zenodo-Dep="3943260" IM.metadata_requiresApprovalFor="plazi" IM.taxonomicNames_requiresApprovalFor="plazi" checkinTime="1593076728220" checkinUser="jeremy" docAuthor="Mary Higby Schweitzer, Jennifer L. Wittmeyer & John R. Horner" docDate="2008" docId="03ED8784AA073131CF9CCFE282721275" docLanguage="en" docName="Schweitzeretal2008ABBYY.pdf.imf" docOrigin="Tyrannosaurus rex, the tyrant king, lndiana University Press" docStyle="DocumentStyle{}" docTitle="Tyrannosaurus rex Osborn 1905" docType="treatment" docVersion="10" lastPageNumber="98" masterDocId="FFD4FFFCAA063137CF28CD4786651B5C" masterDocTitle="One pretty amazing T. rex" masterLastPageNumber="100" masterPageNumber="92" pageNumber="93" updateTime="1698842902033" updateUser="ExternalLinkService">
|
|
<mods:mods id="BC5EF35D085C0C8A8D99680354047B92" xmlns:mods="http://www.loc.gov/mods/v3">
|
|
<mods:titleInfo id="969681C54C8B4DB975799BCBBD484E79">
|
|
<mods:title id="11FB71C2CF9A22910FF5336033DA3AC5">One pretty amazing T. rex</mods:title>
|
|
</mods:titleInfo>
|
|
<mods:name id="D787E932F9B226DB16B1753F3AD61E89" type="personal">
|
|
<mods:role id="85D7EDA4BC4289F3D575858322CEC471">
|
|
<mods:roleTerm id="35A4B7A0722D52F64BF11864C57527C7">Author</mods:roleTerm>
|
|
</mods:role>
|
|
<mods:namePart id="880CA871985E27B42FE3E86774FD1596">Mary Higby Schweitzer</mods:namePart>
|
|
</mods:name>
|
|
<mods:name id="B67A5F6964A4F01EB9E5FB6C68910FD8" type="personal">
|
|
<mods:role id="8B3E49E961E4585D4AB743EBE4BB43D8">
|
|
<mods:roleTerm id="410A6FA6420BA3C441C5B617BBA4994E">Author</mods:roleTerm>
|
|
</mods:role>
|
|
<mods:namePart id="06FD2AFC074F7B57D1337ABC86695BD1">Jennifer L. Wittmeyer</mods:namePart>
|
|
</mods:name>
|
|
<mods:name id="4DE4F33E7F93628D36C683F62601C49D" type="personal">
|
|
<mods:role id="12DA5D55CE1C458684636A34AF6DB6E4">
|
|
<mods:roleTerm id="1277FD2668E123EF0DFB2216E42E550D">Author</mods:roleTerm>
|
|
</mods:role>
|
|
<mods:namePart id="2F2EE083800F342BA623CE13BD35B19D">John R. Horner</mods:namePart>
|
|
</mods:name>
|
|
<mods:typeOfResource id="5C91F2B43FA8FA9A0DAFA90B5BD3C2BC">text</mods:typeOfResource>
|
|
<mods:relatedItem id="1095B5C4BC4EB9075E0BC91BE952EB87" type="host">
|
|
<mods:originInfo id="93156529A58D4A97C12E44638B40E29A">
|
|
<mods:dateIssued id="8322C37B0954F8C37D57139697A27992">2008</mods:dateIssued>
|
|
<mods:dateOther id="90E98B4A8D5F16373605E87AA182CD6C" type="pubDate">2008-12-31</mods:dateOther>
|
|
<mods:publisher id="BA3FB94284B734A046C010BDCB9AB3F9">lndiana University Press</mods:publisher>
|
|
</mods:originInfo>
|
|
<mods:name id="4F11AC3130AA9AC247B667B50C12CED6" type="personal">
|
|
<mods:role id="A24A65A74DC038641F464C01B19288A6">
|
|
<mods:roleTerm id="93000C35C69BB5E57EE0881A87126566">Editor</mods:roleTerm>
|
|
</mods:role>
|
|
<mods:namePart id="08DC2E8C07D4658F4CF61F3E69367B29">Peter Larson</mods:namePart>
|
|
</mods:name>
|
|
<mods:name id="16222CFCF92FCCEF48D6FA59FD229CA1" type="personal">
|
|
<mods:role id="B0CE9D2211BB34D6289E82C97E02BB20">
|
|
<mods:roleTerm id="DB9771AD55C72EC68CB5532843C84A19">Editor</mods:roleTerm>
|
|
</mods:role>
|
|
<mods:namePart id="A6EA2E974EB146DF6773486CBAD0FA33">Kenneth Carpenter</mods:namePart>
|
|
</mods:name>
|
|
<mods:titleInfo id="A91B7848360129A8E2E16814016BF685">
|
|
<mods:title id="6C57DA5B9E505D3D61B4423B4585EA8B">Tyrannosaurus rex, the tyrant king</mods:title>
|
|
</mods:titleInfo>
|
|
<mods:part id="D82FB924DDED4DAFF401B0A949E67BDC">
|
|
<mods:extent id="CBB1FF10604AD4BB7B36165A2FC48ECE" unit="page">
|
|
<mods:start id="F46C3D8ECC939514C4668D06BEA5A173">92</mods:start>
|
|
<mods:end id="6DDBA71BA10179E112EDC09DE9BFC4A6">100</mods:end>
|
|
</mods:extent>
|
|
</mods:part>
|
|
</mods:relatedItem>
|
|
<mods:classification id="DC0D7E8E7BCF6B3CF0F192CF3F633F21">book chapter</mods:classification>
|
|
<mods:identifier id="838655DBCBE2D0C19E62030B441AB2BF" type="CLB-Dataset">21496</mods:identifier>
|
|
<mods:identifier id="57B0BCCE0C7ECB86225D418A7876B069" type="DOI">10.5281/zenodo.3943260</mods:identifier>
|
|
<mods:identifier id="1864CE8400A72907D6234652EDDD0358" type="GBIF-Dataset">3e00ef13-3995-4f38-b69b-6df75b6ee2e5</mods:identifier>
|
|
<mods:identifier id="5E4662A49C03F0DE3C0EBF58DBAAA0A3" type="Zenodo-Dep">3943260</mods:identifier>
|
|
</mods:mods>
|
|
<treatment id="03ED8784AA073131CF9CCFE282721275" ID-DOI="http://doi.org/10.5281/zenodo.5199473" ID-GBIF-Taxon="165074974" ID-Zenodo-Dep="5199473" LSID="urn:lsid:plazi:treatment:03ED8784AA073131CF9CCFE282721275" httpUri="http://treatment.plazi.org/id/03ED8784AA073131CF9CCFE282721275" lastPageId="6" lastPageNumber="98" pageId="1" pageNumber="93">
|
|
<subSubSection id="C35E6519AA073136CF9CCFE28584133A" pageId="1" pageNumber="93" type="discussion">
|
|
<paragraph id="8BFB3692AA073136CF9CCFE285BB1EBB" blockId="1.[179,1420,672,2151]" pageId="1" pageNumber="93">
|
|
Determining sex in extinct animals is difficult because most features commonly used to assign sex are lost in the process of fossilization. Despite this difficulty, many bonv features of dinosaurs have been interpreted to be evidence of sexual dimorphism, including degree of robustness in sauropods and their close relatives (
|
|
<bibRefCitation id="EFD54B63AA073136CD15CE3D823218C2" author="Weishampel, D. B. & Chapman, R. E." box="[573,1111,890,926]" editor="Carpenter, K. & Currie, P. J." journalOrPublisher="Cambridge University Press, Cambridge" pageId="1" pageNumber="93" pagination="43 - 51" refId="ref5026" refString="Weishampel, D. B., and Chapman, R. E. 1990. Morphometric study of Plateosaurus from Trossingen (Baden-Wurttemberg, Federal Republic of Germany). P. 43 - 51 in Carpenter, K., and Currie, P. J. (eds.). Dinosaur Systematics: Approaches and Perspectives. Cambridge University Press, Cambridge" title="Morphometric study of Plateosaurus from Trossingen (Baden-Wurttemberg, Federal Republic of Germany)" type="book chapter" volumeTitle="Dinosaur Systematics: Approaches and Perspectives" year="1990">Weishampel and Chapman 1990</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA073136CB4ECE3D834B18C2" author="Galton, P. M." box="[1126,1326,890,926]" journalOrPublisher="Neues Jahrbuch. fur Geologie und Palaeontologie, Vlonatshefte" pageId="1" pageNumber="93" pagination="674 - 682" part="1997" refId="ref3864" refString="Galton, P. M. 1997. Comments on sexual dimorphism in the prosauropod dinosaur Plateosaurus engelhardti (Upper Triassic, Trossingen). Neues Jahrbuch. fur Geologie und Palaeontologie, Vlonatshefte 1997: 674 - 682." title="Comments on sexual dimorphism in the prosauropod dinosaur Plateosaurus engelhardti (Upper Triassic, Trossingen)" type="journal article" year="1997">Galton 1997</bibRefCitation>
|
|
; Benton etal. 2000), theropods (
|
|
<bibRefCitation id="EFD54B63AA073136CD53CEF785E41888" author="Carpenter, K." box="[635,897,944,980]" editor="Carpenter, K. & Currie, P. J." journalOrPublisher="Cambridge University Press, Cambridge" pageId="1" pageNumber="93" pagination="141 - 146" refId="ref3630" refString="Carpenter, K. 1990. Variations in Tyrannosaurus rex. P. 141 - 146 in Carpenter, K., and Currie, P. J. (eds.). Dinosaur Systematics: Approaches and Perspectives. Cambridge University Press, Cambridge." title="Variations in Tyrannosaurus rex" type="book chapter" volumeTitle="Dinosaur Systematics: Approaches and Perspectives" year="1990">Carpenter 1990</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA073136CCBCCEF782061888" author="Larson, P. L." box="[916,1123,944,980]" editor="Rosenberg, G. D. & Wolberg, D. L." journalOrPublisher="Paleontological Society Special Publication" pageId="1" pageNumber="93" pagination="139 - 155" part="7" refId="ref4199" refString="Larson, P. L. 1994. Tyrannosaurus sex. P. 139 - 155 in Rosenberg, G. D., and Wolberg, D. L. (eds.). Dinofest. Paleontological Society Special Publication 7." title="Tyrannosaurus sex" type="book chapter" volumeTitle="Dinofest" year="1994">Larson 1994</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA073136CB5FCEF783511888" author="Smith, D. K." box="[1143,1332,944,980]" journalOrPublisher="Journal of Vertebrate Paleontology" pageId="1" pageNumber="93" pagination="126 - 142" part="18" refId="ref4765" refString="Smith, D. K. 1998. A morphometric analysis of Allosaurus. Journal of Vertebrate Paleontology 18 (1): 126 - 142." title="A morphometric analysis of Allosaurus" type="journal article" year="1998">Smith 1998</bibRefCitation>
|
|
) and protoceratopsids (
|
|
<bibRefCitation id="EFD54B63AA073136CEFBCEA285B31F55" author="Tereschenko, V. S. & Alifanov, V. R." box="[467,982,997,1033]" journalOrPublisher="Paleontology Journal" pageId="1" pageNumber="93" pagination="293 - 302" part="37" refId="ref4885" refString="Tereschenko, V. S., and Alifanov, V. R. 2003. Bainoceratops efremovi, a new protoceratopsid dinosaur (Protoceratopidae, Neoceratopsia) from the Bain- Dzak locality (south Mongolia). Paleontology Journal 37: 293 - 302." title="Bainoceratops efremovi, a new protoceratopsid dinosaur (Protoceratopidae, Neoceratopsia) from the Bain- Dzak locality (south Mongolia)" type="journal article" year="2003">Tereschenko and Alifanov 2003</bibRefCitation>
|
|
); horn core size in ceratopsids (
|
|
<bibRefCitation id="EFD54B63AA073136CE2EC95D84A71F62" author="Godfrey, S. J. & Holmes, R." box="[262,706,1050,1086]" journalOrPublisher="Journal of Vertebrate Paleontology" pageId="1" pageNumber="93" pagination="726 - 742" part="15" refId="ref3978" refString="Godfrey, S. J., and Holmes, R. 1995. Cranial morphology and svstematics of Ghasmosaurus (Dinosauria: Ceratopsidae) from the Upper Cretaceous of western Canada. Journal of Vertebrate Paleontology 15: 726 - 742." title="Cranial morphology and svstematics of Ghasmosaurus (Dinosauria: Ceratopsidae) from the Upper Cretaceous of western Canada" type="journal article" year="1995">Godfrey and Holmes 1995</bibRefCitation>
|
|
); or presence or absence of the first caudal chevron (Larson and Frey 1992;
|
|
<bibRefCitation id="EFD54B63AA073136CDE9C90885E81F2F" author="Larson, P. L." box="[705,909,1103,1139]" editor="Rosenberg, G. D. & Wolberg, D. L." journalOrPublisher="Paleontological Society Special Publication" pageId="1" pageNumber="93" pagination="139 - 155" part="7" refId="ref4199" refString="Larson, P. L. 1994. Tyrannosaurus sex. P. 139 - 155 in Rosenberg, G. D., and Wolberg, D. L. (eds.). Dinofest. Paleontological Society Special Publication 7." title="Tyrannosaurus sex" type="book chapter" volumeTitle="Dinofest" year="1994">Larson 1994</bibRefCitation>
|
|
), to name a few. However, even if such features could definitively be shown to be products of sexual differentiation, it remains impossible to assign a particular feature unambiguously to a specific sex (e.g., the robust morph being female;
|
|
<bibRefCitation id="EFD54B63AA073136CCD7C9A883601E4F" author="Carpenter, K." box="[1023,1285,1263,1299]" editor="Carpenter, K. & Currie, P. J." journalOrPublisher="Cambridge University Press, Cambridge" pageId="1" pageNumber="93" pagination="141 - 146" refId="ref3630" refString="Carpenter, K. 1990. Variations in Tyrannosaurus rex. P. 141 - 146 in Carpenter, K., and Currie, P. J. (eds.). Dinosaur Systematics: Approaches and Perspectives. Cambridge University Press, Cambridge." title="Variations in Tyrannosaurus rex" type="book chapter" volumeTitle="Dinosaur Systematics: Approaches and Perspectives" year="1990">Carpenter 1990</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA073136CA3FC9A887631E15" author="Larson, P. L." editor="Rosenberg, G. D. & Wolberg, D. L." journalOrPublisher="Paleontological Society Special Publication" pageId="1" pageNumber="93" pagination="139 - 155" part="7" refId="ref4199" refString="Larson, P. L. 1994. Tyrannosaurus sex. P. 139 - 155 in Rosenberg, G. D., and Wolberg, D. L. (eds.). Dinofest. Paleontological Society Special Publication 7." title="Tyrannosaurus sex" type="book chapter" volumeTitle="Dinofest" year="1994">Larson 1994</bibRefCitation>
|
|
). At best, assigning sex to a specific morphotvpe of dinosaurs has fallen within the realm of speculation. What is needed is an unambiguous means of assigning a particular sex to male and female morphs. One possibility is the identification of medullary bone in dinosaurs.
|
|
</paragraph>
|
|
<paragraph id="8BFB3692AA073136CFD7C8BE8584133A" blockId="1.[179,1420,672,2151]" pageId="1" pageNumber="93">
|
|
Medullary bone is an ephemeral reproductive tissue that is present in living taxa and that is found exclusively in female, actively reproducing birds. This bonv tissue lines the medullary cavities of the long bones of extant birds; it is chemically and morphologically distinct from other bone types. Special characteristics of composition and structure contribute to the high metabolic rates of medullary bone. In fact, it is capable of being metabolized 10 to 15 times faster than cortical bone (
|
|
<bibRefCitation id="EFD54B63AA073136CB1ACA7F836E1C00" author="Simkiss, K." box="[1074,1291,1848,1884]" journalOrPublisher="Biological Review" pageId="1" pageNumber="93" pagination="321 - 367" part="36" refId="ref4745" refString="Simkiss, K. 1961. Calcium metabolism and avian reproduction. Biological Review 36: 321 - 367." title="Calcium metabolism and avian reproduction" type="journal article" year="1961">Simkiss 1961</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA073136CA37CA7F87061CCC" author="Dacke, C. G. & Arkle, S. & Cook, D. J. & Wormstone, I. M. & Jones, S. & Zaidi, Al. & Bascal, Z. A." journalOrPublisher="Journal of Experimental Biology" pageId="1" pageNumber="93" pagination="63 - 88" part="184" refId="ref3709" refString="Dacke, C. G., Arkle, S., Cook, D. J., Wormstone, I. M., Jones, S., Zaidi, Al., and Bascal, Z. A. 1993. Medullary bone and avian calcium regulation. Journal of Experimental Biology 184: 63 - 88." title="Medullary bone and avian calcium regulation" type="journal article" year="1993">Dacke et al. 1993</bibRefCitation>
|
|
), and it serves as an easily mobilized calcium storage tissue for the production of calcareous eggshell (
|
|
<bibRefCitation id="EFD54B63AA073136CC6ECAE483261C9B" author="Sugiyama, T. & Kusuhara, S." box="[838,1347,1955,1991]" journalOrPublisher="Asian-Australian Journal ofAnimal Science" pageId="1" pageNumber="93" pagination="82 - 90" part="14" refId="ref4792" refString="Sugiyama, T., and Kusuhara, S. 2001. Avian calcium metabolism and bone function. Asian-Australian Journal ofAnimal Science 14: 82 - 90." title="Avian calcium metabolism and bone function" type="journal article" year="2001">Sugiyama and Kusuhara 2001</bibRefCitation>
|
|
). Its presence in dinosaurs would indicate sex, support phylogenetic proximity, suggest shared reproductive physiological strategies w ith extant birds, and indicate reproductive phase at the time of death.
|
|
</paragraph>
|
|
</subSubSection>
|
|
<subSubSection id="C35E6519AA073133CAFEC5A483EE1FA0" lastPageId="4" lastPageNumber="96" pageId="1" pageNumber="93" type="description">
|
|
<paragraph id="8BFB3692AA073136CAFEC5A4809D129F" blockId="1.[1494,1791,2275,2499]" pageId="1" pageNumber="93">
|
|
<heading id="D0B381FEAA073136CAFEC5A4809E1216" bold="true" centered="true" fontSize="13" level="3" pageId="1" pageNumber="93" reason="0">Comparison of Medullary and</heading>
|
|
<emphasis id="B930EA80AA073136CAFEC41B809D129F" bold="true" pageId="1" pageNumber="93">
|
|
<heading id="D0B381FEAA073136CAFEC41B808112DB" bold="true" box="[1494,1764,2396,2439]" fontSize="13" level="2" pageId="1" pageNumber="93" reason="0">Cortical Bone</heading>
|
|
<heading id="D0B381FEAA073136CAFEC4DF809D129F" bold="true" box="[1494,1784,2456,2499]" centered="true" fontSize="13" level="3" pageId="1" pageNumber="93" reason="0">Characteristics</heading>
|
|
</emphasis>
|
|
</paragraph>
|
|
<paragraph id="8BFB3692AA073136CF9BC5AF832311DD" blockId="1.[178,1419,2274,2692]" pageId="1" pageNumber="93">
|
|
In addition to protection and support ofvital internal organs, bone plays an important role in calcium metabolism in vertebrates, including all avian taxa (
|
|
<bibRefCitation id="EFD54B63AA073136CF97C414840E122B" author="Miller, S. C. & Bowman, B. M." box="[191,619,2387,2423]" journalOrPublisher="Developmental Biology" pageId="1" pageNumber="93" pagination="52 - 63" part="87" refId="ref4419" refString="Miller, S. C., and Bowman, B. M. 1981. Medullary bone osteogenesis following estrogen administration to mature male Japanese quail. Developmental Biology 87: 52 - 63." title="Medullary bone osteogenesis following estrogen administration to mature male Japanese quail" type="journal article" year="1981">Miller and Bowman 1981</bibRefCitation>
|
|
). Long bone formation in extant birds procedes much the same as in other vertebrate taxa through endochondral ossification of preexisting cartilage models (
|
|
<bibRefCitation id="EFD54B63AA073136CDEFC4F9858512BE" author="Whitehead, C. C." box="[711,992,2494,2530]" journalOrPublisher="Poultry Science" pageId="1" pageNumber="93" pagination="193 - 199" part="83" refId="ref5092" refString="Whitehead, C. C. 2004. Overview of bone biology in the egg-laying hen. Poultry Science 83: 193 - 199." title="Overview of bone biology in the egg-laying hen" type="journal article" year="2004">Whitehead 2004</bibRefCitation>
|
|
; Tavlor et al. 1971). Bone elongation involves periosteal deposition, and concurrent endosteal osteoclastic resorption at the metaphyseal region, resulting in overall maintenance ofbone morphology and thickness during longitudinal growth (
|
|
<bibRefCitation id="EFD54B63AA073136CB02C71A835211DD" author="Taylor, T. G. & Simkiss, K. & Stringer, D. A." box="[1066,1335,2653,2689]" editor="Freeman, B. M." journalOrPublisher="Academic Press, New York" pageId="1" pageNumber="93" pagination="621 - 640" refId="ref4821" refString="Taylor, T. G., Simkiss, K., and Stringer, D. A. 1971. The skeleton: its structure and metabolism. P. 621 - 640 in Freeman, B. M. (ed.). Physiology and Biochemistry of the Domestic Fowl. Vol. 2. Academic Press, New York." title="The skeleton: its structure and metabolism" type="book" volumeTitle="Physiology and Biochemistry of the Domestic Fowl. Vol. 2" year="1971">Taylor et al. 1971</bibRefCitation>
|
|
).
|
|
</paragraph>
|
|
<paragraph id="8BFB3692AA043135CDCCCDF480D81806" blockId="2.[664,1914,177,2723]" pageId="2" pageNumber="94">
|
|
In both formation and elongation, bone production involves 2 phases, which reflect the composite nature of bone material. In the first, the boneforming cells (osteoblasts) secrete organic matrix (osteoid) (
|
|
<bibRefCitation id="EFD54B63AA043135C988CC65848C1A2B" author="Taylor, T. G. & Simkiss, K. & Stringer, D. A." editor="Freeman, B. M." journalOrPublisher="Academic Press, New York" pageId="2" pageNumber="94" pagination="621 - 640" refId="ref4821" refString="Taylor, T. G., Simkiss, K., and Stringer, D. A. 1971. The skeleton: its structure and metabolism. P. 621 - 640 in Freeman, B. M. (ed.). Physiology and Biochemistry of the Domestic Fowl. Vol. 2. Academic Press, New York." title="The skeleton: its structure and metabolism" type="book" volumeTitle="Physiology and Biochemistry of the Domestic Fowl. Vol. 2" year="1971">Taylor et al. 1971</bibRefCitation>
|
|
; McKee et al. 1995). This matrix primarily consists of the fibrous helical protein collagen I and the accessory collagen V; the noncollagenous proteins osteocalcin, osteopontin, and osteonectin (
|
|
<bibRefCitation id="EFD54B63AA043135CAD0CC86848F194B" author="Bonucci, E. & Gherardi, G." journalOrPublisher="Cell and Tissue Research" pageId="2" pageNumber="94" pagination="81 - 97" part="163" refId="ref3599" refString="Bonucci, E., and Gherardi, G. 1975. Histochemical and electron microscope investigations on medullary bone. Cell and Tissue Research 163: 81 - 97." title="Histochemical and electron microscope investigations on medullary bone" type="journal article" year="1975">Bonucci and Gherardi 1975</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA043135CDD5CCB4824B1944" author="McKee, M. D. & Farachcarson, M. C. & Butler, W. T. & Hauschka, P. V. & Nanci, A." box="[765,1070,499,536]" journalOrPublisher="Journal of Bone and Mineral Research" pageId="2" pageNumber="94" pagination="485 - 496" part="8" refId="ref4318" refString="McKee, M. D., Farachcarson, M. C., Butler, W. T. Hauschka, P. V., and Nanci, A. 1993. Ultrastructural immunolocalization of noncollagenous (osteopontin and osteocalcin) and plasma (albumin and alpha- 2 HS glycoprotein) proteins in rat bone. Journal of Bone and Mineral Research 8 (4): 485 - 496" title="Ultrastructural immunolocalization of noncollagenous (osteopontin and osteocalcin) and plasma (albumin and alpha- 2 HS glycoprotein) proteins in rat bone" type="journal article" year="1993">McKee et al. 1993</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA043135CB69CCB383A41945" author="Gerstenfeld, L. C." box="[1089,1473,500,537]" journalOrPublisher="Calcified Tissue International" pageId="2" pageNumber="94" pagination="230 - 235" part="55" refId="ref3950" refString="Gerstenfeld, L. C. 1994. Selective extractabilitv of noncollagenous proteins from chicken bone. Calcified Tissue International 55 (3): 230 - 235" title="Selective extractabilitv of noncollagenous proteins from chicken bone" type="journal article" year="1994">Gerstenfeld et al. 1994</bibRefCitation>
|
|
; Sugiyama and Kasuhura 2001;
|
|
<bibRefCitation id="EFD54B63AA043135CC28CF6E82481912" author="Wang, X. & Ford, B. C. & Praul, C. A. & Leach, R. M." box="[768,1069,553,590]" journalOrPublisher="Comparative Biochemistry and Physiology B" pageId="2" pageNumber="94" pagination="665 - 572" part="140" refId="ref4975" refString="Wang, X., Ford, B. C., Praul, C. A., and Leach, R. M. 2005. Characterization of the non-collagenous proteins in avian cortical and medullary bone. Comparative Biochemistry and Physiology B 140: 665 - 572." title="Characterization of the non-collagenous proteins in avian cortical and medullary bone" type="journal volume" year="2005">Wang et al. 2005</bibRefCitation>
|
|
), and bone sialoprotein (
|
|
<bibRefCitation id="EFD54B63AA043135CAF6CF6C8102190C" author="Gerstenfeld, L. C." box="[1502,1895,555,592]" journalOrPublisher="Calcified Tissue International" pageId="2" pageNumber="94" pagination="230 - 235" part="55" refId="ref3950" refString="Gerstenfeld, L. C. 1994. Selective extractabilitv of noncollagenous proteins from chicken bone. Calcified Tissue International 55 (3): 230 - 235" title="Selective extractabilitv of noncollagenous proteins from chicken bone" type="journal article" year="1994">Gerstenfeld et al. 1994</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA043135CDB2CF19853F19DE" author="Robey, P. G." box="[666,858,606,642]" journalOrPublisher="Connective Tissue Research" pageId="2" pageNumber="94" pagination="185 - 190" part="35" refId="ref4578" refString="Robey, P. G. 1996. Vertebrate mineralized matrix proteins: structure and function. Connective Tissue Research 35 (1 - 4): 185 - 190." title="Vertebrate mineralized matrix proteins: structure and function" type="journal article" year="1996">Robey 1996</bibRefCitation>
|
|
and references therein); serum proteins, including hemoglobin and albumin (
|
|
<bibRefCitation id="EFD54B63AA043135CCBBCFD382B619E4" author="McKee, M. D. & Farachcarson, M. C. & Butler, W. T. & Hauschka, P. V. & Nanci, A." box="[915,1235,660,696]" journalOrPublisher="Journal of Bone and Mineral Research" pageId="2" pageNumber="94" pagination="485 - 496" part="8" refId="ref4318" refString="McKee, M. D., Farachcarson, M. C., Butler, W. T. Hauschka, P. V., and Nanci, A. 1993. Ultrastructural immunolocalization of noncollagenous (osteopontin and osteocalcin) and plasma (albumin and alpha- 2 HS glycoprotein) proteins in rat bone. Journal of Bone and Mineral Research 8 (4): 485 - 496" title="Ultrastructural immunolocalization of noncollagenous (osteopontin and osteocalcin) and plasma (albumin and alpha- 2 HS glycoprotein) proteins in rat bone" type="journal article" year="1993">McKee et al. 1993</bibRefCitation>
|
|
); and various glycosaminoglycans (
|
|
<bibRefCitation id="EFD54B63AA043135C81DCFD1822E19B2" author="Bonucci, E. & Gherardi, G." journalOrPublisher="Cell and Tissue Research" pageId="2" pageNumber="94" pagination="81 - 97" part="163" refId="ref3599" refString="Bonucci, E., and Gherardi, G. 1975. Histochemical and electron microscope investigations on medullary bone. Cell and Tissue Research 163: 81 - 97." title="Histochemical and electron microscope investigations on medullary bone" type="journal article" year="1975">Bonucci and Gherardi 1975</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA043135CB4ACF8D83EB19B3" author="Dacke, C. G. & Arkle, S. & Cook, D. J. & Wormstone, I. M. & Jones, S. & Zaidi, Al. & Bascal, Z. A." box="[1122,1422,714,751]" journalOrPublisher="Journal of Experimental Biology" pageId="2" pageNumber="94" pagination="63 - 88" part="184" refId="ref3709" refString="Dacke, C. G., Arkle, S., Cook, D. J., Wormstone, I. M., Jones, S., Zaidi, Al., and Bascal, Z. A. 1993. Medullary bone and avian calcium regulation. Journal of Experimental Biology 184: 63 - 88." title="Medullary bone and avian calcium regulation" type="journal article" year="1993">Dacke et al. 1993</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA043135CA8BCF8C810D19AC" author="Arias, J. L. & Fernandez, M. S." box="[1443,1896,715,752]" journalOrPublisher="World Poultry Science Journal" pageId="2" pageNumber="94" pagination="349 - 355" part="57" refId="ref3466" refString="Arias, J. L., and Fernandez, M. S. 2001. Role of extracellular matrix molecules in shell formation and structure. World Poultry Science Journal 57: 349 - 355." title="Role of extracellular matrix molecules in shell formation and structure" type="journal article" year="2001">Arias and Fernandez 2001</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA043135CDB0CFB985A0187F" author="Wang, X. & Ford, B. C. & Praul, C. A. & Leach, R. M." box="[664,965,766,803]" journalOrPublisher="Comparative Biochemistry and Physiology B" pageId="2" pageNumber="94" pagination="665 - 572" part="140" refId="ref4975" refString="Wang, X., Ford, B. C., Praul, C. A., and Leach, R. M. 2005. Characterization of the non-collagenous proteins in avian cortical and medullary bone. Comparative Biochemistry and Physiology B 140: 665 - 572." title="Characterization of the non-collagenous proteins in avian cortical and medullary bone" type="journal volume" year="2005">
|
|
<emphasis id="B930EA80AA043135CDB0CFB98498187E" box="[664,765,766,802]" italics="true" pageId="2" pageNumber="94">Wang</emphasis>
|
|
et al. 2005
|
|
</bibRefCitation>
|
|
). Therefore, cortical and trabecular bone have specific, characteristic, and defineable chemical and molecular profiles.
|
|
</paragraph>
|
|
<paragraph id="8BFB3692AA043135CDCECE2F810918A6" blockId="2.[664,1914,177,2723]" pageId="2" pageNumber="94">
|
|
However, in female birds, a unique bone type is formed as the result of a surge in blood estrogen levels at the onset of sexual maturity (
|
|
<bibRefCitation id="EFD54B63AA043135C9B6CED885ED18A4" author="Bonucci, E. & Gherardi, G." journalOrPublisher="Cell and Tissue Research" pageId="2" pageNumber="94" pagination="81 - 97" part="163" refId="ref3599" refString="Bonucci, E., and Gherardi, G. 1975. Histochemical and electron microscope investigations on medullary bone. Cell and Tissue Research 163: 81 - 97." title="Histochemical and electron microscope investigations on medullary bone" type="journal article" year="1975">Bonucci and Gherardi 1975</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA043135CCB3CE93836E18A5" author="Knott, L. & Bailey, A. J." box="[923,1291,980,1017]" journalOrPublisher="British Poultry Science" pageId="2" pageNumber="94" pagination="371 - 379" part="40" refId="ref4162" refString="Knott, L., and Bailey, A. J. 1999. Collagen biochemistry of avian bone: comparison of bone type and skeletal site. British Poultry Science 40: 371 - 379." title="Collagen biochemistry of avian bone: comparison of bone type and skeletal site" type="journal article" year="1999">Knott and Bailey 1999</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA043135CA34CE92805218A5" author="Dacke, C. G. & Arkle, S. & Cook, D. J. & Wormstone, I. M. & Jones, S. & Zaidi, Al. & Bascal, Z. A." box="[1308,1591,981,1017]" journalOrPublisher="Journal of Experimental Biology" pageId="2" pageNumber="94" pagination="63 - 88" part="184" refId="ref3709" refString="Dacke, C. G., Arkle, S., Cook, D. J., Wormstone, I. M., Jones, S., Zaidi, Al., and Bascal, Z. A. 1993. Medullary bone and avian calcium regulation. Journal of Experimental Biology 184: 63 - 88." title="Medullary bone and avian calcium regulation" type="journal article" year="1993">Dacke et al. 1993</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA043135C96ECE91813918A6" author="Whitehead, C. C." box="[1606,1884,982,1018]" journalOrPublisher="Poultry Science" pageId="2" pageNumber="94" pagination="193 - 199" part="83" refId="ref5092" refString="Whitehead, C. C. 2004. Overview of bone biology in the egg-laying hen. Poultry Science 83: 193 - 199." title="Overview of bone biology in the egg-laying hen" type="journal article" year="2004">Whitehead 2004</bibRefCitation>
|
|
).
|
|
</paragraph>
|
|
<paragraph id="8BFB3692AA043135CDB3C94F81081E65" blockId="2.[664,1914,177,2723]" pageId="2" pageNumber="94">
|
|
Medullary bone does not occur naturally in any other taxon (
|
|
<bibRefCitation id="EFD54B63AA043135C958C94C848E1F3C" author="Elsey, R. M. & Wink, C. S." journalOrPublisher="Comparative Biochemistry and Physiology" pageId="2" pageNumber="94" pagination="107 - 110" part="84 A" refId="ref3771" refString="Elsey, R. M., and Wink, C. S. 1986. The effects of estradiol on plasma calcium and femoral bone structure in alligators (Alligator mississippiensis). Comparative Biochemistry and Physiology 84 A: 107 - 110." title="The effects of estradiol on plasma calcium and femoral bone structure in alligators (Alligator mississippiensis)" type="journal article" year="1986">Elsey and Wink 1986</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA043135CDD4C97B82771F3D" author="Dacke, C. G. & Arkle, S. & Cook, D. J. & Wormstone, I. M. & Jones, S. & Zaidi, Al. & Bascal, Z. A." box="[764,1042,1084,1121]" journalOrPublisher="Journal of Experimental Biology" pageId="2" pageNumber="94" pagination="63 - 88" part="184" refId="ref3709" refString="Dacke, C. G., Arkle, S., Cook, D. J., Wormstone, I. M., Jones, S., Zaidi, Al., and Bascal, Z. A. 1993. Medullary bone and avian calcium regulation. Journal of Experimental Biology 184: 63 - 88." title="Medullary bone and avian calcium regulation" type="journal article" year="1993">Dacke et al. 1993</bibRefCitation>
|
|
), and it is present only during the reproductive period in all living female birds, filling the marrow cavities of many skeletal elements (Wilson and Thorpe 1998;
|
|
<bibRefCitation id="EFD54B63AA043135CBF0C9EE805C1F91" author="Van Neer, W. & Noven, K. & DeCupere, B." box="[1240,1593,1193,1229]" journalOrPublisher="Journal of Archeological Science" pageId="2" pageNumber="94" pagination="123 - 134" part="29" refId="ref4931" refString="Van Neer, W., Noven, K., and DeCupere, B. 2002. On the use of endosteal layers and medullarv bone from domestic fowl in archaeozoological studies. Journal of Archeological Science 29: 123 - 134." title="On the use of endosteal layers and medullarv bone from domestic fowl in archaeozoological studies" type="journal article" year="2002">Van Neer et al. 2002</bibRefCitation>
|
|
). It is produced byspecialized osteoblasts that lie within the endosteum, a thin connective tissue layer that lines the marrow surfaces of the bones (
|
|
<bibRefCitation id="EFD54B63AA043135C921C853813B1E65" author="Van Neer, W. & Noven, K. & DeCupere, B." box="[1545,1886,1300,1337]" journalOrPublisher="Journal of Archeological Science" pageId="2" pageNumber="94" pagination="123 - 134" part="29" refId="ref4931" refString="Van Neer, W., Noven, K., and DeCupere, B. 2002. On the use of endosteal layers and medullarv bone from domestic fowl in archaeozoological studies. Journal of Archeological Science 29: 123 - 134." title="On the use of endosteal layers and medullarv bone from domestic fowl in archaeozoological studies" type="journal article" year="2002">Van Neer et al. 2002</bibRefCitation>
|
|
).
|
|
</paragraph>
|
|
<paragraph id="8BFB3692AA043135CDB3C80080841DF2" blockId="2.[664,1914,177,2723]" pageId="2" pageNumber="94">
|
|
Medullary bone exists only to offset the effects of bone resorption during shelling by serving as an easily mobilized source of calcium, and it has no direct biomechanical function (
|
|
<bibRefCitation id="EFD54B63AA043135CB91C8F380F31E85" author="Bonucci, E. & Gherardi, G." box="[1209,1686,1460,1497]" journalOrPublisher="Cell and Tissue Research" pageId="2" pageNumber="94" pagination="81 - 97" part="163" refId="ref3599" refString="Bonucci, E., and Gherardi, G. 1975. Histochemical and electron microscope investigations on medullary bone. Cell and Tissue Research 163: 81 - 97." title="Histochemical and electron microscope investigations on medullary bone" type="journal article" year="1975">Bonucci and Gherardi 1975</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA043135C985C8F285041D57" author="Wilson, S. & Thorp, B. H." journalOrPublisher="Calcified Tissue International" pageId="2" pageNumber="94" pagination="506 - 511" part="62" refId="ref5117" refString="Wilson, S., and Thorp, B. H. 1998. Estrogen and cancellous bone loss in the fowl. Calcified Tissue International 62: 506 - 511." title="Estrogen and cancellous bone loss in the fowl" type="journal article" year="1998">Wilson and Thorp 1998</bibRefCitation>
|
|
). It is chemically and morphologically distinct from other bone types. Although medullary bone has been assumed to be present in extant paleognaths, it has not been previously imaged or studied, and no data exist regarding the morphology or chemistry of this bone type in ratites.
|
|
</paragraph>
|
|
<paragraph id="8BFB3692AA043135CDCECBFB8172116B" blockId="2.[664,1914,177,2723]" pageId="2" pageNumber="94">
|
|
The mineral phase of both medullary and cortical bone is primarily hydroxyapatite (Ca10(PO4)6(OH)2), but the ratio of mineral to organics is measurably higher in medullary bone (
|
|
<bibRefCitation id="EFD54B63AA043135CA3FCA60802D1C17" author="Ascenzi, A. & Francois, C. & Bocciarelli, D. S." box="[1303,1608,1831,1867]" journalOrPublisher="Journal of Ultrastructure Research" pageId="2" pageNumber="94" pagination="491 - 505" part="8" refId="ref3503" refString="Ascenzi, A., Francois, C., and Bocciarelli, D. S. 1963. On the bone induced by estrogens in birds. Journal of Ultrastructure Research 8: 491 - 505." title="On the bone induced by estrogens in birds" type="journal article" year="1963">Ascenzi et al. 1963</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA043135C97ECA6F810C1C10" author="Taylor, T. G. & Simkiss, K. & Stringer, D. A." box="[1622,1897,1832,1868]" editor="Freeman, B. M." journalOrPublisher="Academic Press, New York" pageId="2" pageNumber="94" pagination="621 - 640" refId="ref4821" refString="Taylor, T. G., Simkiss, K., and Stringer, D. A. 1971. The skeleton: its structure and metabolism. P. 621 - 640 in Freeman, B. M. (ed.). Physiology and Biochemistry of the Domestic Fowl. Vol. 2. Academic Press, New York." title="The skeleton: its structure and metabolism" type="book" volumeTitle="Physiology and Biochemistry of the Domestic Fowl. Vol. 2" year="1971">Taylor et al. 1971</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA043135CDB4CA1C85DF1CDC" author="Dacke, C. G. & Arkle, S. & Cook, D. J. & Wormstone, I. M. & Jones, S. & Zaidi, Al. & Bascal, Z. A." box="[668,954,1883,1920]" journalOrPublisher="Journal of Experimental Biology" pageId="2" pageNumber="94" pagination="63 - 88" part="184" refId="ref3709" refString="Dacke, C. G., Arkle, S., Cook, D. J., Wormstone, I. M., Jones, S., Zaidi, Al., and Bascal, Z. A. 1993. Medullary bone and avian calcium regulation. Journal of Experimental Biology 184: 63 - 88." title="Medullary bone and avian calcium regulation" type="journal article" year="1993">Dacke et al. 1993</bibRefCitation>
|
|
), and medullary bone incorporates a higher proportion of calcium carbonate (
|
|
<bibRefCitation id="EFD54B63AA043135CCF7CAD583151CEB" author="Pelligrino, E. D. & Blitz, R. M." box="[991,1392,1938,1975]" journalOrPublisher="Calcified Tissue Research" pageId="2" pageNumber="94" pagination="168 - 171" part="6" refId="ref4501" refString="Pelligrino, E. D., and Blitz, R. M. 1970. Calcium carbonate in medullary bone. Calcified Tissue Research 6: 168 - 171." title="Calcium carbonate in medullary bone" type="journal article" year="1970">Pelligrino and Blitz 1970</bibRefCitation>
|
|
) than other bone types. Medullary bone is not only more highly mineralized than cortical bone, but also the distribution of minerals is different between the 2 bone types. In cortical bone, the mineral crystals are regularly distributed at the head of the A bands of collagen molecules (
|
|
<bibRefCitation id="EFD54B63AA043135CB37C521832713D7" author="Taylor, T. G. & Simkiss, K. & Stringer, D. A." box="[1055,1346,2150,2187]" editor="Freeman, B. M." journalOrPublisher="Academic Press, New York" pageId="2" pageNumber="94" pagination="621 - 640" refId="ref4821" refString="Taylor, T. G., Simkiss, K., and Stringer, D. A. 1971. The skeleton: its structure and metabolism. P. 621 - 640 in Freeman, B. M. (ed.). Physiology and Biochemistry of the Domestic Fowl. Vol. 2. Academic Press, New York." title="The skeleton: its structure and metabolism" type="book" volumeTitle="Physiology and Biochemistry of the Domestic Fowl. Vol. 2" year="1971">Taylor et al. 1971</bibRefCitation>
|
|
), but in medullary bone, mineral distribution and orientation is much more random, with mineral crystals additionally deposited in intrafibrillar spaces (
|
|
<bibRefCitation id="EFD54B63AA043135CABEC59580B513AB" author="Ascenzi, A. & Francois, C. & Bocciarelli, D. S." box="[1430,1744,2258,2295]" journalOrPublisher="Journal of Ultrastructure Research" pageId="2" pageNumber="94" pagination="491 - 505" part="8" refId="ref3503" refString="Ascenzi, A., Francois, C., and Bocciarelli, D. S. 1963. On the bone induced by estrogens in birds. Journal of Ultrastructure Research 8: 491 - 505." title="On the bone induced by estrogens in birds" type="journal article" year="1963">Ascenzi et al. 1963</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA043135C9C9C594857D1275" author="Taylor, T. G. & Simkiss, K. & Stringer, D. A." editor="Freeman, B. M." journalOrPublisher="Academic Press, New York" pageId="2" pageNumber="94" pagination="621 - 640" refId="ref4821" refString="Taylor, T. G., Simkiss, K., and Stringer, D. A. 1971. The skeleton: its structure and metabolism. P. 621 - 640 in Freeman, B. M. (ed.). Physiology and Biochemistry of the Domestic Fowl. Vol. 2. Academic Press, New York." title="The skeleton: its structure and metabolism" type="book" volumeTitle="Physiology and Biochemistry of the Domestic Fowl. Vol. 2" year="1971">Taylor et al. 1971</bibRefCitation>
|
|
). In addition, medullary bone does not exhibit birefringence because of the random arrangement of both collagen fibrils and mineral, whereas other bone types are anisotropic in polarized light (
|
|
<bibRefCitation id="EFD54B63AA043135C93FC435848D1295" author="Miller, S. C. & Bowman, B. M." journalOrPublisher="Developmental Biology" pageId="2" pageNumber="94" pagination="52 - 63" part="87" refId="ref4419" refString="Miller, S. C., and Bowman, B. M. 1981. Medullary bone osteogenesis following estrogen administration to mature male Japanese quail. Developmental Biology 87: 52 - 63." title="Medullary bone osteogenesis following estrogen administration to mature male Japanese quail" type="journal article" year="1981">Miller and Bowman 1981</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA043135CDDFC4E282191296" author="Wilson, S. & Thorp, B. H." box="[759,1148,2469,2506]" journalOrPublisher="Calcified Tissue International" pageId="2" pageNumber="94" pagination="506 - 511" part="62" refId="ref5117" refString="Wilson, S., and Thorp, B. H. 1998. Estrogen and cancellous bone loss in the fowl. Calcified Tissue International 62: 506 - 511." title="Estrogen and cancellous bone loss in the fowl" type="journal article" year="1998">Wilson and Thorp 1998</bibRefCitation>
|
|
). Finally, the mineral crystals incorporated into medullary bone are somewhat larger than the microcrystalline apatite of other bone types (
|
|
<bibRefCitation id="EFD54B63AA043135CC49C75682F41169" author="Ascenzi, A. & Francois, C. & Bocciarelli, D. S." box="[865,1169,2577,2613]" journalOrPublisher="Journal of Ultrastructure Research" pageId="2" pageNumber="94" pagination="491 - 505" part="8" refId="ref3503" refString="Ascenzi, A., Francois, C., and Bocciarelli, D. S. 1963. On the bone induced by estrogens in birds. Journal of Ultrastructure Research 8: 491 - 505." title="On the bone induced by estrogens in birds" type="journal article" year="1963">Ascenzi et al. 1963</bibRefCitation>
|
|
), producing a greater crystallinity index.
|
|
</paragraph>
|
|
<paragraph id="8BFB3692AA043134CDCEC70284A81812" blockId="2.[664,1914,177,2723]" lastBlockId="3.[152,1393,168,850]" lastPageId="3" lastPageNumber="95" pageId="2" pageNumber="94">
|
|
The organic phase of medullary bone differs significantly from that of cortical and trabecular bone. Collagen makes up a greater proportion of the organic matrix of cortical bone, whereas the percentage of noncollagenous proteins to collagen is far greater in medullary bone, comprising approximately 40% of the total organics (
|
|
<bibRefCitation id="EFD54B63AA053134CD9ACC5F82441A60" author="Knott, L. & Bailey, A. J." box="[690,1057,280,316]" journalOrPublisher="British Poultry Science" pageId="3" pageNumber="95" pagination="371 - 379" part="40" refId="ref4162" refString="Knott, L., and Bailey, A. J. 1999. Collagen biochemistry of avian bone: comparison of bone type and skeletal site. British Poultry Science 40: 371 - 379." title="Collagen biochemistry of avian bone: comparison of bone type and skeletal site" type="journal article" year="1999">Knott and Bailey 1999</bibRefCitation>
|
|
). The concentration of various glyclosaminoglycans is greater in medullary than cortical bone, and it incorporates different amino sugars (
|
|
<bibRefCitation id="EFD54B63AA053134CC55CCC6833E1AF9" author="Bonucci, E. & Gherardi, G." box="[893,1371,385,421]" journalOrPublisher="Cell and Tissue Research" pageId="3" pageNumber="95" pagination="81 - 97" part="163" refId="ref3599" refString="Bonucci, E., and Gherardi, G. 1975. Histochemical and electron microscope investigations on medullary bone. Cell and Tissue Research 163: 81 - 97." title="Histochemical and electron microscope investigations on medullary bone" type="journal article" year="1975">Bonucci and Gherardi 1975</bibRefCitation>
|
|
). Hexosamine and keratan sulfate are much more prevalent in medullary than cortical bone (
|
|
<bibRefCitation id="EFD54B63AA053134CEAACCAA84F0194C" author="Taylor, T. G. & Simkiss, K. & Stringer, D. A." box="[386,661,492,529]" editor="Freeman, B. M." journalOrPublisher="Academic Press, New York" pageId="3" pageNumber="95" pagination="621 - 640" refId="ref4821" refString="Taylor, T. G., Simkiss, K., and Stringer, D. A. 1971. The skeleton: its structure and metabolism. P. 621 - 640 in Freeman, B. M. (ed.). Physiology and Biochemistry of the Domestic Fowl. Vol. 2. Academic Press, New York." title="The skeleton: its structure and metabolism" type="book" volumeTitle="Physiology and Biochemistry of the Domestic Fowl. Vol. 2" year="1971">Taylor et al. 1971</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA053134CD8BCCAB85D3194C" author="Wang, X. & Ford, B. C. & Praul, C. A. & Leach, R. M." box="[675,950,492,528]" journalOrPublisher="Comparative Biochemistry and Physiology B" pageId="3" pageNumber="95" pagination="665 - 572" part="140" refId="ref4975" refString="Wang, X., Ford, B. C., Praul, C. A., and Leach, R. M. 2005. Characterization of the non-collagenous proteins in avian cortical and medullary bone. Comparative Biochemistry and Physiology B 140: 665 - 572." title="Characterization of the non-collagenous proteins in avian cortical and medullary bone" type="journal volume" year="2005">Wang et al. 2005</bibRefCitation>
|
|
), which incorporates chondroitin sulfate instead. In addition, relatively high concentrations of tartrateresistant acid phosphatase (TRAP), an enzyme involved in digestion of bone (
|
|
<bibRefCitation id="EFD54B63AA053134CF8DCFCA84EB19EC" author="Sugiyama, T. & Kusuhara, S." box="[165,654,652,689]" journalOrPublisher="Asian-Australian Journal ofAnimal Science" pageId="3" pageNumber="95" pagination="82 - 90" part="14" refId="ref4792" refString="Sugiyama, T., and Kusuhara, S. 2001. Avian calcium metabolism and bone function. Asian-Australian Journal ofAnimal Science 14: 82 - 90." title="Avian calcium metabolism and bone function" type="journal article" year="2001">Sugiyama and Kusuhara 2001</bibRefCitation>
|
|
), are found in medullary bone. These chemical differences are reflected in the differential response of the 2 bone types to various histochemical stains (
|
|
<figureCitation id="137F2A17AA053134CD9DCFB185551846" box="[693,816,758,794]" captionStart="Figure 7.1" captionText="Figure 7.1. Medullary bone in extant laying hen. (A) Gross cross section of femur of actively laying hen shows extensive medullary bone formation. New bone is randomly oriented and much more porous than overlying cortical bone. (B) Low magnification and (C) high magnification of histological section of demineralized bone from laying hen. Chemical differences between cortical and medullary bone are indicated by differential response of each bone type to hematoxylin and eosin staining. In (C), separation of the medullary bone from cortical bone is seen as sectioning artifact. Large, multinucleated osteoclasts are visible around bone spicules, and small osteoblasts align along preexisting bone spicules, active in deposition of new bone. Abbreviations: CB, cortical bone; MB, medullary bone; ELB, endosteal laminar bone; OCL, osteocyte lacunae; OC, osteoclast; OB, osteoblast. Scales as indicated. See color version of this figure in the accompanying CD-ROM " figureDoi="http://doi.org/10.5281/zenodo.3943264" httpUri="https://zenodo.org/record/3943264/files/figure.png" pageId="3" pageNumber="95" targetBox="[926,1696,2252,2910]" targetPageId="1">Fig. 7.1</figureCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA053134CC6ECFB1820C1846" author="Taylor, T. G. & Simkiss, K. & Stringer, D. A." box="[838,1129,758,794]" editor="Freeman, B. M." journalOrPublisher="Academic Press, New York" pageId="3" pageNumber="95" pagination="621 - 640" refId="ref4821" refString="Taylor, T. G., Simkiss, K., and Stringer, D. A. 1971. The skeleton: its structure and metabolism. P. 621 - 640 in Freeman, B. M. (ed.). Physiology and Biochemistry of the Domestic Fowl. Vol. 2. Academic Press, New York." title="The skeleton: its structure and metabolism" type="book" volumeTitle="Physiology and Biochemistry of the Domestic Fowl. Vol. 2" year="1971">Taylor et al. 1971</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA053134CBA9CFB187F61813" author="Sugiyama, T. & Kusuhara, S." journalOrPublisher="Asian-Australian Journal ofAnimal Science" pageId="3" pageNumber="95" pagination="82 - 90" part="14" refId="ref4792" refString="Sugiyama, T., and Kusuhara, S. 2001. Avian calcium metabolism and bone function. Asian-Australian Journal ofAnimal Science 14: 82 - 90." title="Avian calcium metabolism and bone function" type="journal article" year="2001">Sugiyama and Kusuhara 2001</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA053134CE8CCE6C84DB1812" author="Wang, X. & Ford, B. C. & Praul, C. A. & Leach, R. M." box="[420,702,810,847]" journalOrPublisher="Comparative Biochemistry and Physiology B" pageId="3" pageNumber="95" pagination="665 - 572" part="140" refId="ref4975" refString="Wang, X., Ford, B. C., Praul, C. A., and Leach, R. M. 2005. Characterization of the non-collagenous proteins in avian cortical and medullary bone. Comparative Biochemistry and Physiology B 140: 665 - 572." title="Characterization of the non-collagenous proteins in avian cortical and medullary bone" type="journal volume" year="2005">Wang et al. 2005</bibRefCitation>
|
|
).
|
|
</paragraph>
|
|
<paragraph id="8BFB3692AA053134CA95CE8A80981F68" blockId="3.[1468,1789,971,1076]" pageId="3" pageNumber="95">
|
|
<heading id="D0B381FEAA053134CA95CE8A80C618A4" bold="true" box="[1469,1699,973,1016]" fontSize="14" level="1" pageId="3" pageNumber="95" reason="0">
|
|
<emphasis id="B930EA80AA053134CA95CE8A800F18A4" bold="true" box="[1469,1642,973,1016]" pageId="3" pageNumber="95">Function</emphasis>
|
|
of
|
|
</heading>
|
|
<heading id="D0B381FEAA053134CA95C94E80981F68" bold="true" box="[1469,1789,1033,1076]" centered="true" fontSize="14" level="3" pageId="3" pageNumber="95" reason="0">
|
|
Medullary
|
|
<emphasis id="B930EA80AA053134C9B2C94E80981F68" bold="true" box="[1690,1789,1033,1076]" pageId="3" pageNumber="95">Bone</emphasis>
|
|
</heading>
|
|
</paragraph>
|
|
<paragraph id="8BFB3692AA053134CFB1CE94849413AE" blockId="3.[152,1394,973,2720]" pageId="3" pageNumber="95">
|
|
Unlike other bone types, medullary bone has no biomechanical or other supportive function. It exists solely as a calcium storage tissue that aids in mineral mobilization to the shell gland during lay (
|
|
<bibRefCitation id="EFD54B63AA053134CCFAC97B828C1F3C" author="Dacke, C. G. & Arkle, S. & Cook, D. J. & Wormstone, I. M. & Jones, S. & Zaidi, Al. & Bascal, Z. A." box="[978,1257,1084,1120]" journalOrPublisher="Journal of Experimental Biology" pageId="3" pageNumber="95" pagination="63 - 88" part="184" refId="ref3709" refString="Dacke, C. G., Arkle, S., Cook, D. J., Wormstone, I. M., Jones, S., Zaidi, Al., and Bascal, Z. A. 1993. Medullary bone and avian calcium regulation. Journal of Experimental Biology 184: 63 - 88." title="Medullary bone and avian calcium regulation" type="journal article" year="1993">Dacke et al. 1993</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA053134CBDEC97B87D71FC4" author="Wilson, S. & Thorp, B. H." journalOrPublisher="Calcified Tissue International" pageId="3" pageNumber="95" pagination="506 - 511" part="62" refId="ref5117" refString="Wilson, S., and Thorp, B. H. 1998. Estrogen and cancellous bone loss in the fowl. Calcified Tissue International 62: 506 - 511." title="Estrogen and cancellous bone loss in the fowl" type="journal article" year="1998">Wilson and Thorp 1998</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA053134CEEEC93384821FCB" author="Whitehead, C. C." box="[454,743,1139,1176]" journalOrPublisher="Poultry Science" pageId="3" pageNumber="95" pagination="193 - 199" part="83" refId="ref5092" refString="Whitehead, C. C. 2004. Overview of bone biology in the egg-laying hen. Poultry Science 83: 193 - 199." title="Overview of bone biology in the egg-laying hen" type="journal article" year="2004">Whitehead 2004</bibRefCitation>
|
|
). As mentioned previously, medullary-bone formation in birds is triggered by increased levels of both estrogen and androgens that accompany ovulation, activating osteoblasts to begin secretion of osteoid while inhibiting osteoclast activity (
|
|
<bibRefCitation id="EFD54B63AA053134CCE7C856828E1E69" author="Dacke, C. G. & Arkle, S. & Cook, D. J. & Wormstone, I. M. & Jones, S. & Zaidi, Al. & Bascal, Z. A." box="[975,1259,1297,1333]" journalOrPublisher="Journal of Experimental Biology" pageId="3" pageNumber="95" pagination="63 - 88" part="184" refId="ref3709" refString="Dacke, C. G., Arkle, S., Cook, D. J., Wormstone, I. M., Jones, S., Zaidi, Al., and Bascal, Z. A. 1993. Medullary bone and avian calcium regulation. Journal of Experimental Biology 184: 63 - 88." title="Medullary bone and avian calcium regulation" type="journal article" year="1993">Dacke et al. 1993</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA053134CBD2C856872D1E37" author="Whitehead, C. C." journalOrPublisher="Poultry Science" pageId="3" pageNumber="95" pagination="193 - 199" part="83" refId="ref5092" refString="Whitehead, C. C. 2004. Overview of bone biology in the egg-laying hen. Poultry Science 83: 193 - 199." title="Overview of bone biology in the egg-laying hen" type="journal article" year="2004">Whitehead 2004</bibRefCitation>
|
|
). The formation of medullary bone begins approximately 1 or 2 weeks before lay. It is maintained during the full laying cycle, and it may persist up to 1 week after lay before resorption is complete (
|
|
<bibRefCitation id="EFD54B63AA053134CB49C8F6833E1E89" author="Reynolds, S. J." box="[1121,1371,1457,1493]" journalOrPublisher="Auk" pageId="3" pageNumber="95" pagination="224 - 228" part="120" refId="ref4532" refString="Reynolds, S. J. 2003. Mineral retention, medullary bone formation and reproduction in the white-tailed ptarmigan (Lagopus leucurus): a critique of Larson et al. (2001). Auk 120 (1): 224 - 228." title="Mineral retention, medullary bone formation and reproduction in the white-tailed ptarmigan (Lagopus leucurus): a critique of Larson et al. (2001)" type="journal article" year="2003">Reynolds 2003</bibRefCitation>
|
|
). Medullary bone osteoclasts in female birds are specialized to contain estrogen receptors in their cell membranes, which, when triggered by rising reproductive hormones, increases the efficiency of mobilizing stored calcium (
|
|
<bibRefCitation id="EFD54B63AA053134CF8DCBC187001DF6" author="Miller, S. C." box="[165,357,1670,1706]" journalOrPublisher="American Journal ofAnatomy" pageId="3" pageNumber="95" pagination="35 - 43" part="162" refId="ref4390" refString="Miller, S. C. 1981. Osteoclast cell-surface specializations and nuclear kinetics during egglaying in Japanese quail. American Journal ofAnatomy 162: 35 - 43." title="Osteoclast cell-surface specializations and nuclear kinetics during egglaying in Japanese quail" type="journal article" year="1981">Miller 1981</bibRefCitation>
|
|
). Although evidence of medullary bone may be found in virtually all skeletal elements of extant birds, it is most abundant in the femur and tibiotarsus of most birds studied (
|
|
<bibRefCitation id="EFD54B63AA053134CDE6CBA885AD1C4F" author="Reynolds, S. J." box="[718,968,1775,1811]" journalOrPublisher="Auk" pageId="3" pageNumber="95" pagination="224 - 228" part="120" refId="ref4532" refString="Reynolds, S. J. 2003. Mineral retention, medullary bone formation and reproduction in the white-tailed ptarmigan (Lagopus leucurus): a critique of Larson et al. (2001). Auk 120 (1): 224 - 228." title="Mineral retention, medullary bone formation and reproduction in the white-tailed ptarmigan (Lagopus leucurus): a critique of Larson et al. (2001)" type="journal article" year="2003">Reynolds 2003</bibRefCitation>
|
|
), and, consistent with its function as a source of rapid calcium mobilization, it is infused with abundant vessels and blood sinuses. In fact, up to 40% of the calcium used in eggshell formation comes directly from the resorption of medullary bone (
|
|
<bibRefCitation id="EFD54B63AA053134CA22CAC8871C1CB6" author="Mueller, W. J. & Brubaker, R. L. & Caplan, M. D." journalOrPublisher="Federation of the American Society of Experimental Biologists" pageId="3" pageNumber="95" pagination="1851 - 1855" part="28" refId="ref4455" refString="Mueller, W. J., Brubaker, R. L., and Caplan, M. D. 1969. Eggshell formation and bone resorption in egg-laying hens. Federation of the American Society of Experimental Biologists 28: 1851 - 1855." title="Eggshell formation and bone resorption in egg-laying hens" type="journal article" year="1969">Mueller et al. 1969</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA053134CEA4CA8184CC1CB5" author="Dacke, C. G. & Arkle, S. & Cook, D. J. & Wormstone, I. M. & Jones, S. & Zaidi, Al. & Bascal, Z. A." box="[396,681,1989,2026]" journalOrPublisher="Journal of Experimental Biology" pageId="3" pageNumber="95" pagination="63 - 88" part="184" refId="ref3709" refString="Dacke, C. G., Arkle, S., Cook, D. J., Wormstone, I. M., Jones, S., Zaidi, Al., and Bascal, Z. A. 1993. Medullary bone and avian calcium regulation. Journal of Experimental Biology 184: 63 - 88." title="Medullary bone and avian calcium regulation" type="journal article" year="1993">Dacke et al. 1993</bibRefCitation>
|
|
). Although it is not known to serve a direct mechanical function, in reducing the resorption of cortical and trabecular bone, it may aid in maintaining integrity and strength of structurally important bone (
|
|
<bibRefCitation id="EFD54B63AA053134CE60C522843B13D5" author="Whitehead, C. C." box="[328,606,2149,2185]" journalOrPublisher="Poultry Science" pageId="3" pageNumber="95" pagination="193 - 199" part="83" refId="ref5092" refString="Whitehead, C. C. 2004. Overview of bone biology in the egg-laying hen. Poultry Science 83: 193 - 199." title="Overview of bone biology in the egg-laying hen" type="journal article" year="2004">Whitehead 2004</bibRefCitation>
|
|
), and indeed, the presence of medullary bone in long bones of laying birds has been shown to increase fracture resistance of these elements (
|
|
<bibRefCitation id="EFD54B63AA053134CE8AC588848713AE" author="Fleming, R. H. & McCormack, H. A. & McTeir, L. & Whitehead, C. C." box="[418,738,2254,2291]" journalOrPublisher="Research in Veterinary Science" pageId="3" pageNumber="95" pagination="63 - 67" part="64" refId="ref3816" refString="Fleming, R. H., McCormack, H. A., McTeir, L., and Whitehead, C. C. 1998. Medullarv bone and humeral breaking strength in laying hens. Research in Veterinary Science 64: 63 - 67." title="Medullarv bone and humeral breaking strength in laying hens" type="journal article" year="1998">Fleming et al. 1998</bibRefCitation>
|
|
).
|
|
</paragraph>
|
|
<paragraph id="8BFB3692AA053134CFCCC44282A911C2" blockId="3.[152,1394,973,2720]" pageId="3" pageNumber="95">
|
|
Like birds, most reptiles, including crocodiles and alligators, also produce calcareous eggshell, but apparently do not produce medullary bone (
|
|
<bibRefCitation id="EFD54B63AA053134CF8DC437846E12C8" author="Elsey, R. M. & Wink, C. S." box="[165,523,2416,2452]" journalOrPublisher="Comparative Biochemistry and Physiology" pageId="3" pageNumber="95" pagination="107 - 110" part="84 A" refId="ref3771" refString="Elsey, R. M., and Wink, C. S. 1986. The effects of estradiol on plasma calcium and femoral bone structure in alligators (Alligator mississippiensis). Comparative Biochemistry and Physiology 84 A: 107 - 110." title="The effects of estradiol on plasma calcium and femoral bone structure in alligators (Alligator mississippiensis)" type="journal article" year="1986">
|
|
<emphasis id="B930EA80AA053134CF8DC437876512C8" box="[165,256,2416,2452]" italics="true" pageId="3" pageNumber="95">Elsey</emphasis>
|
|
and Wink 1986
|
|
</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA053134CD34C428855D12CF" author="Dacke, C. G. & Arkle, S. & Cook, D. J. & Wormstone, I. M. & Jones, S. & Zaidi, Al. & Bascal, Z. A." box="[540,824,2415,2451]" journalOrPublisher="Journal of Experimental Biology" pageId="3" pageNumber="95" pagination="63 - 88" part="184" refId="ref3709" refString="Dacke, C. G., Arkle, S., Cook, D. J., Wormstone, I. M., Jones, S., Zaidi, Al., and Bascal, Z. A. 1993. Medullary bone and avian calcium regulation. Journal of Experimental Biology 184: 63 - 88." title="Medullary bone and avian calcium regulation" type="journal article" year="1993">Dacke et al. 1993</bibRefCitation>
|
|
). This may be because of different mechanisms of shelling (
|
|
<bibRefCitation id="EFD54B63AA053134CD12C4E285141295" author="Jackson, F. D. & Schweitzer, M. H. & Schmitt, J. G." box="[570,881,2469,2505]" journalOrPublisher="Scanning" pageId="3" pageNumber="95" pagination="217 - 223" part="24" refId="ref4124" refString="Jackson, F. D., Schweitzer, M. H., and Schmitt, J. G. 2002. Dinosaur eggshell study using scanning electron microscopy. Scanning 24: 217 - 223." title="Dinosaur eggshell study using scanning electron microscopy" type="journal article" year="2002">Jackson et al. 2002</bibRefCitation>
|
|
) and overall greater bone density that can offset the calcium draw without requiring additional bone storage sources. Thus, extant nonavian archosaurs undergo bone resorption during lay, but the structural integrity and biomechanical function of these organisms is apparently not compromised during shelling.
|
|
</paragraph>
|
|
<paragraph id="8BFB3692AA023133CDC1CDEA83EE1FA0" blockId="4.[672,1915,170,1277]" pageId="4" pageNumber="96">
|
|
Although medullary bone has not been previously observed or described in dinosaurs, it was proposed that reproducing dinosaurs, at least in the theropod lineage most closely related to avian dinosaurs, would possess this ephemeral tissue (
|
|
<bibRefCitation id="EFD54B63AA023133CB72CC0983E31A2F" author="Martill, D. M & Barker, M. J. & Dacke, C. G." box="[1114,1414,334,371]" journalOrPublisher="Nature" pageId="4" pageNumber="96" pagination="778 - 778" part="379" refId="ref4284" refString="Martill, D. M " Barker, M. J., and Dacke, C. G. 1996. Dinosaur nesting or preying? Nature 379: 778 - 778." title="Dinosaur nesting or preying?" type="journal article" year="1996">Martill et al. 1996</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA023133CABFCC0881061A28" author="Chinsamy, A. & Barrett, P. M." box="[1431,1891,335,372]" journalOrPublisher="Journal of Vertebrate Paleontology" pageId="4" pageNumber="96" pagination="450 - 450" part="17" refId="ref3677" refString="Chinsamy, A., and Barrett, P. M. 1997. Sex and old bones? Journal of Vertebrate Paleontology 17 (2): 450 - 450." title="Sex and old bones?" type="journal article" year="1997">Chinsamy and Barrett 1997</bibRefCitation>
|
|
). The failure to observe or identify these fragile reproductive tissues in dinosaurs previously may be due to a number of taphonomic and/or biological factors, or observational bias. First, we do not have anv way of estimating the length of the reproductive cvcle in theropods. There is a wide range of reproductive strategies among living birds, and the extent and distribution of medullary bone in these taxa differ correspondingly (
|
|
<bibRefCitation id="EFD54B63AA023133C985CFC8851019B9" author="Schraer, H. & Hunter, S. J." journalOrPublisher="Comparative Biochemistry and Biophysiology" pageId="4" pageNumber="96" pagination="13 - 17" part="82 A (1)" refId="ref4609" refString="Schraer, H., and Hunter, S. J. 1985. The development of medullary bone: a model for osteogenesis. Comparative Biochemistry and Biophysiology 82 A (1): 13 - 17." title="The development of medullary bone: a model for osteogenesis" type="journal article" year="1985">Schraer and Hunter 1985</bibRefCitation>
|
|
). If theropods reproduce seasonally, they may
|
|
<emphasis id="B930EA80AA023133C959CF8480DC19BB" box="[1649,1721,707,743]" italics="true" pageId="4" pageNumber="96">only</emphasis>
|
|
possess the tissue for a maximum of a month or less. Second, because of the relativ ely thick, dense cortex, the need for medullary bone may be less in these animals, so the medullary layer may be quite thin. Third, in extant birds, the tissue is quite fragile, and separates easily from the overlying cortex (
|
|
<figureCitation id="137F2A17AA023133C81ECEDE84B618B3" captionStart="Figure 7.1" captionText="Figure 7.1. Medullary bone in extant laying hen. (A) Gross cross section of femur of actively laying hen shows extensive medullary bone formation. New bone is randomly oriented and much more porous than overlying cortical bone. (B) Low magnification and (C) high magnification of histological section of demineralized bone from laying hen. Chemical differences between cortical and medullary bone are indicated by differential response of each bone type to hematoxylin and eosin staining. In (C), separation of the medullary bone from cortical bone is seen as sectioning artifact. Large, multinucleated osteoclasts are visible around bone spicules, and small osteoblasts align along preexisting bone spicules, active in deposition of new bone. Abbreviations: CB, cortical bone; MB, medullary bone; ELB, endosteal laminar bone; OCL, osteocyte lacunae; OC, osteoclast; OB, osteoblast. Scales as indicated. See color version of this figure in the accompanying CD-ROM " figureDoi="http://doi.org/10.5281/zenodo.3943264" httpUri="https://zenodo.org/record/3943264/files/figure.png" pageId="4" pageNumber="96" targetBox="[926,1696,2252,2910]" targetPageId="1">Fig. 7.1</figureCitation>
|
|
B, C). It may be that the tissues are lost, either during fossilization or during subsequent recovery and preparation. Third, it may be that medullary bone differs sufficiently from that of extant derived birds so that it is not recognized.
|
|
<emphasis id="B930EA80AA023133CC99C92B85A91FCC" box="[945,972,1132,1168]" italics="true" pageId="4" pageNumber="96">A</emphasis>
|
|
fourth factor may be the failure to examine bones for its presence because of collection techniques requiring bone to be conserved, and not broken to expose interior fragments.
|
|
</paragraph>
|
|
</subSubSection>
|
|
<subSubSection id="C35E6519AA023133CF95C83087571E87" pageId="4" pageNumber="96" type="nomenclature">
|
|
<paragraph id="8BFB3692AA023133CF95C83087571E87" blockId="4.[189,559,1398,1499]" pageId="4" pageNumber="96">
|
|
<heading id="D0B381FEAA023133CF95C830844A1EFE" bold="true" box="[189,559,1399,1442]" fontSize="12" level="5" pageId="4" pageNumber="96" reason="0">
|
|
Medullary
|
|
<emphasis id="B930EA80AA023133CEB2C830879A1EFE" bold="true" box="[410,511,1399,1442]" pageId="4" pageNumber="96">Bone</emphasis>
|
|
in
|
|
</heading>
|
|
<heading id="D0B381FEAA023133CF97C8FD87571E87" bold="true" box="[191,306,1466,1499]" fontSize="12" level="5" pageId="4" pageNumber="96" reason="0">
|
|
<taxonomicName id="4C444D11AA023133CF97C8FD87571E87" authorityName="Osborn" authorityYear="1905" box="[191,306,1466,1499]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" kingdom="Animalia" order="Dinosauria" pageId="4" pageNumber="96" phylum="Chordata" rank="species" species="rex">
|
|
<emphasis id="B930EA80AA023133CF97C8FD87571E87" box="[191,306,1466,1499]" italics="true" pageId="4" pageNumber="96">T. Rex</emphasis>
|
|
</taxonomicName>
|
|
</heading>
|
|
</paragraph>
|
|
</subSubSection>
|
|
<subSubSection id="C35E6519AA023133CD89C83C850D123C" pageId="4" pageNumber="96" type="materials_examined">
|
|
<paragraph id="8BFB3692AA023133CD89C83C82AB1CB6" blockId="4.[673,1917,1400,2722]" pageId="4" pageNumber="96">
|
|
At the end of field season in 2002, a well-preserved specimen of
|
|
<taxonomicName id="4C444D11AA023133C9CEC839852C1E8F" authorityName="Osborn" authorityYear="1905" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="4" pageNumber="96" phylum="Chordata" rank="species" species="rex">
|
|
<emphasis id="B930EA80AA023133C9CEC839852C1E8F" italics="true" pageId="4" pageNumber="96">Tyrannosaurus rex</emphasis>
|
|
</taxonomicName>
|
|
(
|
|
<materialsCitation id="3B2C3CCFAA023133CC4DC8F682781E89" ID-GBIF-Occurrence="2813104309" box="[869,1053,1457,1493]" collectionCode="MOR" pageId="4" pageNumber="96" specimenCode="MOR 1125">MOR 1125</materialsCitation>
|
|
) was found as an association of disarticulated elements. The site was located at the base of the Hell Creek Formation (Lancian), about 8 m above the Fox Hills Sandstone. Soft, well-sorted sandstones derived from an estuarine or fluvial setting surrounded the skeletal elements. Some of the elements evidenced slight crushing, but overall preservation was excellent.
|
|
<materialsCitation id="3B2C3CCFAA023133CB0FCBFB82BA1DBC" ID-GBIF-Occurrence="2813104311" box="[1063,1247,1724,1760]" collectionCode="MOR" pageId="4" pageNumber="96" specimenCode="MOR 1125">MOR 1125</materialsCitation>
|
|
, nicknamed Bob-rex after its discoverer, Bob Harmon, is a relatively small but fully adult
|
|
<taxonomicName id="4C444D11AA023133CAE0CBB580471C49" authorityName="Osborn" authorityYear="1905" box="[1480,1570,1777,1814]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" kingdom="Animalia" order="Dinosauria" pageId="4" pageNumber="96" phylum="Chordata" rank="species" species="rex">
|
|
T.
|
|
<emphasis id="B930EA80AA023133CAD9CBB680471C49" box="[1521,1570,1777,1813]" italics="true" pageId="4" pageNumber="96">rex</emphasis>
|
|
</taxonomicName>
|
|
<emphasis id="B930EA80AA023133C90ACBB680431C49" box="[1570,1574,1777,1813]" italics="true" pageId="4" pageNumber="96">.</emphasis>
|
|
In comparison with another
|
|
<taxonomicName id="4C444D11AA023133CC19CA6285EB1C16" authorityName="Osborn" authorityYear="1905" box="[817,910,1829,1866]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" kingdom="Animalia" order="Dinosauria" pageId="4" pageNumber="96" phylum="Chordata" rank="species" species="rex">
|
|
T.
|
|
<emphasis id="B930EA80AA023133CC74CA6185EB1C16" box="[860,910,1830,1866]" italics="true" pageId="4" pageNumber="96">rex</emphasis>
|
|
</taxonomicName>
|
|
<emphasis id="B930EA80AA023133CCA6CA6185F11C16" box="[910,916,1830,1866]" italics="true" pageId="4" pageNumber="96">,</emphasis>
|
|
<materialsCitation id="3B2C3CCFAA023133CC89CA6182D61C16" ID-GBIF-Occurrence="2813104303" box="[929,1203,1830,1866]" collectionCode="FMNH" pageId="4" pageNumber="96" specimenCode="FMNH PR2081">FMNH PR2081</materialsCitation>
|
|
, with a femur length of about 131 cm, the femur of
|
|
<materialsCitation id="3B2C3CCFAA023133CC6ACA1B859F1CDC" ID-GBIF-Occurrence="2813104304" box="[834,1018,1884,1920]" collectionCode="MOR" pageId="4" pageNumber="96" specimenCode="MOR 1125">MOR 1125</materialsCitation>
|
|
is only' 107 cm in length. By use of lines of arrested growth,
|
|
<materialsCitation id="3B2C3CCFAA023133CC19CAD6858D1CE9" ID-GBIF-Occurrence="2813104302" box="[817,1000,1937,1973]" collectionCode="MOR" pageId="4" pageNumber="96" specimenCode="MOR 1125">MOR 1125</materialsCitation>
|
|
was calculated to be about 18 years old at the time of death (
|
|
<bibRefCitation id="EFD54B63AA023133CC32CA8182DB1CB6" author="Horner, J. R. & Padian, K." box="[794,1214,1990,2026]" journalOrPublisher="Proceedings of the Royal Society of London Series B" pageId="4" pageNumber="96" pagination="1875 - 1880" part="271" refId="ref4071" refString="Horner, J. R., and Padian, K. 2004. Age and growth dynamics of Tyrannosaurus rex. Proceedings of the Royal Society of London Series B 271: 1875 - 1880." title="Age and growth dynamics of Tyrannosaurus rex" type="journal article" year="2004">Horner and Padian 2004</bibRefCitation>
|
|
).
|
|
</paragraph>
|
|
<paragraph id="8BFB3692AA023133CDC6CABC850D123C" blockId="4.[673,1917,1400,2722]" pageId="4" pageNumber="96">
|
|
The remote region where
|
|
<materialsCitation id="3B2C3CCFAA023133CB8CCABA8332137D" ID-GBIF-Occurrence="2813104310" box="[1188,1367,2045,2081]" collectionCode="MOR" pageId="4" pageNumber="96" specimenCode="MOR 1125">MOR 1125</materialsCitation>
|
|
was recovered had no roads into the site, so a helicopter was required to transport field jackets to the MOR laboratories. However, the jacket containing the femur and other elements was too heavy to be airlifted out, and the jacket and bones they contained were broken and rejacketed for removal. In the process, many internal fragments that were visually free of preservative or consolidants were collected for analyses.
|
|
</paragraph>
|
|
</subSubSection>
|
|
<subSubSection id="C35E6519AA023132CDC6C42985A711C0" lastPageId="5" lastPageNumber="97" pageId="4" pageNumber="96" type="description">
|
|
<paragraph id="8BFB3692AA023132CDC6C42983441EC2" blockId="4.[673,1917,1400,2722]" lastBlockId="5.[158,1400,1185,2718]" lastPageId="5" lastPageNumber="97" pageId="4" pageNumber="96">
|
|
When these fragments were examined in hand sample, a bony tissue lining the endosteal surface of the bone could be seen that was distinct in texture, appearance, and distribution from other described dinosaur bone tvpes. The morphological similarity of the new tissues to avian medullary bone was immediately apparent (Schweitzer et al. 2005b).
|
|
<figureCitation id="137F2A17AA023133C940C70081681137" box="[1640,1805,2631,2667]" captionStart="Figure 7.2" captionText="Figure 7.2. Fresh fracture of tibiae of MOR 1125 (A, B), ostrich (C), and emu (D). Morphology and microstructure of medullary bone is observed in all cases as distinct from overlying cortical bone. Medullary bone is less organized and more vascular. Large vascular sinuses can be seen in the medullary bone, and in some cases, large erosion cavities (*) are visible at the interface between medullary and cortical bone and in the medullary bone itself, indicating some resorption of bone has occurred. In emu (D), a large elongate erosion room is infilled with new medullary bone with characteristic corrugated texture. Abbreviations as in Figure 7.1. T, trabecular spicule. Scales as indicated. See color version of this figure in the accompanying CD-ROM. " figureDoi="http://doi.org/10.5281/zenodo.3943266" httpUri="https://zenodo.org/record/3943266/files/figure.png" pageId="4" pageNumber="96" targetBox="[157,1400,173,1102]" targetPageId="5">Figure 7.2</figureCitation>
|
|
shows fresh-fracture images of
|
|
<taxonomicName id="4C444D11AA023133CB13C73E830011C2" authorityName="Osborn" authorityYear="1905" box="[1083,1381,2681,2718]" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="4" pageNumber="96" phylum="Chordata" rank="species" species="rex">
|
|
Tyrannosaurus
|
|
<emphasis id="B930EA80AA023133CA10C73D830011C2" box="[1336,1381,2682,2718]" italics="true" pageId="4" pageNumber="96">rex</emphasis>
|
|
</taxonomicName>
|
|
endosteal tissues (
|
|
<figureCitation id="137F2A17AA023133C9B7C73B817B11FC" box="[1695,1822,2684,2720]" captionStart="Figure 7.2" captionText="Figure 7.2. Fresh fracture of tibiae of MOR 1125 (A, B), ostrich (C), and emu (D). Morphology and microstructure of medullary bone is observed in all cases as distinct from overlying cortical bone. Medullary bone is less organized and more vascular. Large vascular sinuses can be seen in the medullary bone, and in some cases, large erosion cavities (*) are visible at the interface between medullary and cortical bone and in the medullary bone itself, indicating some resorption of bone has occurred. In emu (D), a large elongate erosion room is infilled with new medullary bone with characteristic corrugated texture. Abbreviations as in Figure 7.1. T, trabecular spicule. Scales as indicated. See color version of this figure in the accompanying CD-ROM. " figureDoi="http://doi.org/10.5281/zenodo.3943266" httpUri="https://zenodo.org/record/3943266/files/figure.png" pageId="4" pageNumber="96" targetBox="[157,1400,173,1102]" targetPageId="5">Fig. 7.2</figureCitation>
|
|
<emphasis id="B930EA80AA023133C836C73B815F11FC" box="[1822,1850,2684,2720]" italics="true" pageId="4" pageNumber="96">A</emphasis>
|
|
, B), compared with medullary bone tissues in reproducing ostrich (
|
|
<figureCitation id="137F2A17AA033132CBE5C9E1832B1F96" box="[1229,1358,1190,1226]" captionStart="Figure 7.2" captionText="Figure 7.2. Fresh fracture of tibiae of MOR 1125 (A, B), ostrich (C), and emu (D). Morphology and microstructure of medullary bone is observed in all cases as distinct from overlying cortical bone. Medullary bone is less organized and more vascular. Large vascular sinuses can be seen in the medullary bone, and in some cases, large erosion cavities (*) are visible at the interface between medullary and cortical bone and in the medullary bone itself, indicating some resorption of bone has occurred. In emu (D), a large elongate erosion room is infilled with new medullary bone with characteristic corrugated texture. Abbreviations as in Figure 7.1. T, trabecular spicule. Scales as indicated. See color version of this figure in the accompanying CD-ROM. " figureDoi="http://doi.org/10.5281/zenodo.3943266" httpUri="https://zenodo.org/record/3943266/files/figure.png" pageId="5" pageNumber="97" targetBox="[157,1400,173,1102]" targetPageId="5">Fig. 7.2</figureCitation>
|
|
C) and emu (
|
|
<figureCitation id="137F2A17AA033132CE60C99B87AC1E5C" box="[328,457,1244,1280]" captionStart="Figure 7.2" captionText="Figure 7.2. Fresh fracture of tibiae of MOR 1125 (A, B), ostrich (C), and emu (D). Morphology and microstructure of medullary bone is observed in all cases as distinct from overlying cortical bone. Medullary bone is less organized and more vascular. Large vascular sinuses can be seen in the medullary bone, and in some cases, large erosion cavities (*) are visible at the interface between medullary and cortical bone and in the medullary bone itself, indicating some resorption of bone has occurred. In emu (D), a large elongate erosion room is infilled with new medullary bone with characteristic corrugated texture. Abbreviations as in Figure 7.1. T, trabecular spicule. Scales as indicated. See color version of this figure in the accompanying CD-ROM. " figureDoi="http://doi.org/10.5281/zenodo.3943266" httpUri="https://zenodo.org/record/3943266/files/figure.png" pageId="5" pageNumber="97" targetBox="[157,1400,173,1102]" targetPageId="5">Fig. 7.2</figureCitation>
|
|
D). The hallmark traits of medullary bone—dense vascularity and random, woven bone pattern—are clearly visible in all samples. Large erosion cavities are visible in all medullary tissues (indicated with an asterisk in figures), indicating that calcium mobilization has occurred.
|
|
</paragraph>
|
|
<caption id="DF3B661AAA033132CAEACDF181401D2F" ID-DOI="http://doi.org/10.5281/zenodo.3943266" ID-Zenodo-Dep="3943266" httpUri="https://zenodo.org/record/3943266/files/figure.png" pageId="5" pageNumber="97" startId="5.[1474,1570,182,212]" subCaptionStartIDs="5.[1513,1612,1429,1459] 5.[1584,1677,1574,1604]" subCaptionStarts="Figure 7 & figure i" targetBox="[157,1400,173,1102]" targetPageId="5">
|
|
<paragraph id="8BFB3692AA033132CAEACDF181401D2F" blockId="5.[1471,1886,177,1654]" pageId="5" pageNumber="97">
|
|
Figure 7.2.
|
|
<emphasis id="B930EA80AA033132C95CCDF180A01B88" box="[1652,1733,182,212]" italics="true" pageId="5" pageNumber="97">Fresh</emphasis>
|
|
fracture of
|
|
<emphasis id="B930EA80AA033132CAC6CDA180211A58" box="[1518,1604,230,260]" italics="true" pageId="5" pageNumber="97">tibiae</emphasis>
|
|
of
|
|
<materialsCitation id="3B2C3CCFAA033132C953CDA181411A58" ID-GBIF-Occurrence="2813104306" box="[1659,1828,230,260]" collectionCode="MOR" pageId="5" pageNumber="97" specimenCode="MOR 1125">MOR 1125</materialsCitation>
|
|
<emphasis id="B930EA80AA033132C807CDA183831A68" italics="true" pageId="5" pageNumber="97">(A, B),</emphasis>
|
|
ostrich
|
|
<emphasis id="B930EA80AA033132C943CC5180101A68" box="[1643,1653,278,308]" italics="true" pageId="5" pageNumber="97">(</emphasis>
|
|
C
|
|
<emphasis id="B930EA80AA033132C9A3CC5180FF1A68" box="[1675,1690,278,308]" italics="true" pageId="5" pageNumber="97">),</emphasis>
|
|
and emu
|
|
<emphasis id="B930EA80AA033132CAEACC0183961A38" box="[1474,1523,326,356]" italics="true" pageId="5" pageNumber="97">(D).</emphasis>
|
|
Morphology and
|
|
<emphasis id="B930EA80AA033132C832CC0180E71AC8" italics="true" pageId="5" pageNumber="97">microstructure</emphasis>
|
|
of medullary bone
|
|
<emphasis id="B930EA80AA033132C935CCE180511A98" box="[1565,1588,422,452]" italics="true" pageId="5" pageNumber="97">is</emphasis>
|
|
observed
|
|
<emphasis id="B930EA80AA033132C9F4CCE180251AA8" italics="true" pageId="5" pageNumber="97">in all cases as</emphasis>
|
|
distinct from overlying cortical bone. Medullary bone
|
|
<emphasis id="B930EA80AA033132C9E1CF7180CD19D8" italics="true" pageId="5" pageNumber="97">is less organized and</emphasis>
|
|
more
|
|
<emphasis id="B930EA80AA033132C83ACF21806819EF" italics="true" pageId="5" pageNumber="97">vascular</emphasis>
|
|
. Large vascular
|
|
<emphasis id="B930EA80AA033132C824CFD2816F19B8" italics="true" pageId="5" pageNumber="97">sinuses can be seen in</emphasis>
|
|
the medullary bone, and
|
|
<emphasis id="B930EA80AA033132C830CFB181571848" box="[1816,1842,758,788]" italics="true" pageId="5" pageNumber="97">in</emphasis>
|
|
some
|
|
<emphasis id="B930EA80AA033132C909CE61801F1818" box="[1569,1658,806,836]" italics="true" pageId="5" pageNumber="97">cases,</emphasis>
|
|
large
|
|
<emphasis id="B930EA80AA033132C9CDCE6181321818" box="[1765,1879,806,836]" italics="true" pageId="5" pageNumber="97">erosion</emphasis>
|
|
cavities
|
|
<emphasis id="B930EA80AA033132C917CE1180011828" box="[1599,1636,854,884]" italics="true" pageId="5" pageNumber="97">(*)</emphasis>
|
|
are visible at the interface between medullary and cortical bone and
|
|
<emphasis id="B930EA80AA033132C94DCEA180E51F58" box="[1637,1664,998,1028]" italics="true" pageId="5" pageNumber="97">in</emphasis>
|
|
the medullary bone itself,
|
|
<emphasis id="B930EA80AA033132C9EAC95181391F68" box="[1730,1884,1046,1076]" italics="true" pageId="5" pageNumber="97">indicating</emphasis>
|
|
some resorption of bone has
|
|
<emphasis id="B930EA80AA033132C92AC93280DA1FCF" box="[1538,1727,1141,1171]" italics="true" pageId="5" pageNumber="97">occurred. In</emphasis>
|
|
emu
|
|
<emphasis id="B930EA80AA033132C837C93281351FCF" box="[1823,1872,1141,1171]" italics="true" pageId="5" pageNumber="97">(D),</emphasis>
|
|
a large elongate
|
|
<emphasis id="B930EA80AA033132C9E7C9E281271F9F" box="[1743,1858,1189,1219]" italics="true" pageId="5" pageNumber="97">erosion</emphasis>
|
|
room
|
|
<emphasis id="B930EA80AA033132C90AC99180521FA8" box="[1570,1591,1238,1268]" italics="true" pageId="5" pageNumber="97">is</emphasis>
|
|
infilled with new medullary bone with
|
|
<emphasis id="B930EA80AA033132CAEAC87280F61E0F" box="[1474,1683,1333,1363]" italics="true" pageId="5" pageNumber="97">characteristic</emphasis>
|
|
corrugated texture.
|
|
<emphasis id="B930EA80AA033132C96EC82181401ED8" box="[1606,1829,1382,1412]" italics="true" pageId="5" pageNumber="97">Abbreviations</emphasis>
|
|
as
|
|
<emphasis id="B930EA80AA033132CAE9C8D280C91EEF" box="[1473,1708,1429,1459]" italics="true" pageId="5" pageNumber="97">in Figure 7.1. T,</emphasis>
|
|
trabecular
|
|
<emphasis id="B930EA80AA033132CAE8C88180561EB8" box="[1472,1587,1478,1508]" italics="true" pageId="5" pageNumber="97">spicule.</emphasis>
|
|
Scales
|
|
<emphasis id="B930EA80AA033132C985C881807F1D48" italics="true" pageId="5" pageNumber="97">
|
|
<emphasis id="B930EA80AA033132C985C88180AA1EB8" bold="true" box="[1709,1743,1478,1508]" italics="true" pageId="5" pageNumber="97">as</emphasis>
|
|
indicated
|
|
</emphasis>
|
|
.
|
|
<emphasis id="B930EA80AA033132C905C8B180031D48" box="[1581,1638,1526,1556]" italics="true" pageId="5" pageNumber="97">See</emphasis>
|
|
color version of this
|
|
<emphasis id="B930EA80AA033132C918CB6180D61D18" box="[1584,1715,1574,1604]" italics="true" pageId="5" pageNumber="97">figure in</emphasis>
|
|
the
|
|
<emphasis id="B930EA80AA033132C9D5CB6180E01D2F" italics="true" pageId="5" pageNumber="97">accompanying</emphasis>
|
|
CD-ROM.
|
|
</paragraph>
|
|
</caption>
|
|
<paragraph id="8BFB3692AA033132CFC3C8F784181C4E" blockId="5.[158,1400,1185,2718]" pageId="5" pageNumber="97">
|
|
Demineralization of extant bony tissues is commonly used to more clearly observe microstructural characteristics, such as fibril orientation; and when mineral is removed, the primarily collagenous protein matrix is exposed. Conventional wisdom has held that when fossilized dinosaur bone is subjected to the same treatment, the bone would dissolve completely because no proteinaceous material would persist over the course of geological time (
|
|
<bibRefCitation id="EFD54B63AA033132CE92CBA984081C4E" author="Hoss, M." box="[442,621,1774,1810]" journalOrPublisher="Nature" pageId="5" pageNumber="97" pagination="453 - 454" part="404" refId="ref4108" refString="Hoss, M. 2000. Neanderthal population genetics. Nature 404: 453 - 454" title="Neanderthal population genetics" type="journal article" year="2000">Hoss 2000</bibRefCitation>
|
|
).
|
|
</paragraph>
|
|
<paragraph id="8BFB3692AA033132CFC3CA6385A711C0" blockId="5.[158,1400,1185,2718]" pageId="5" pageNumber="97">
|
|
In order to determine characteristics of presumed medullary tissues, we prepared a partial demineralization designed to etch mineral enough to expose underlying patterns. At this point, we discovered an unexpected and novel characteristic to this bony tissue. As minerals were dissolved from the medullary bone, the sample did not disintegrate, but, similar to extant bone, tissues remained (
|
|
<bibRefCitation id="EFD54B63AA033132CEE0C5698521130E" author="Schweitzer, M. H. & Wittmeyer, J. L. & Horner, J. R. & Toporski, J." box="[456,836,2094,2130]" journalOrPublisher="Science" pageId="5" pageNumber="97" pagination="1952 - 1955" part="307" refId="ref4648" refString="Schweitzer, M. H., Wittmeyer, J. L., and Horner, J. R., and Toporski, J. 2005 a. Soft tissue vessels and cellular preservation in Tyrannosaurus rex. Science 307: 1952 - 1955." title="Soft tissue vessels and cellular preservation in Tyrannosaurus rex" type="journal article" year="2005">Schweitzer et al. 2005a</bibRefCitation>
|
|
). Furthermore, these dinosaur tissues exhibited apparent original flexibility, comparable to that seen in extant ratites. However, these characteristics are not germane to this chapter and will be discussed elsewhere. The retention of a pliable and fibrous matrix after demineralization speaks to unusual preservation in this dinosaur material and suggests that perhaps theorized modes of fossilization may need to be reevaluated.
|
|
<figureCitation id="137F2A17AA033132CE5AC428847312CF" box="[370,534,2415,2451]" captionStart="Figure 7.3" captionText="Figure 7.3. Demineralized fragments of medullary bone from emu (A) and MOR 1125 (B). The fibrous, woven pattern of bone matrix is visible in both cases, and the relatively lacy appearance results from penetration of the bone by blood vessels. Scales as indicated. For methods on demineralization, see Schweitzer et al. (2005a), supplemental online information. See color version of this figure in the accompanying CD-ROM " figureDoi="http://doi.org/10.5281/zenodo.3943268" httpUri="https://zenodo.org/record/3943268/files/figure.png" pageId="5" pageNumber="97" targetBox="[166,1896,168,942]" targetPageId="6">Figure 7.3</figureCitation>
|
|
demonstrates the persistence of fibrous tissues after demineralization. Small fragments of emu and dinosaur demineralized medullary bone tissues show random fiber orientation, and large open spaces for vessels and vascular sinuses permeate the tissues. The morphological similarity between extant and fossil samples is clearly visible and supports the hypothesis of a common origin to the tissues.
|
|
</paragraph>
|
|
</subSubSection>
|
|
<subSubSection id="C35E6519AA003131CF83C94382721275" pageId="6" pageNumber="98" type="discussion">
|
|
<paragraph id="8BFB3692AA003131CF83C94387E11F73" blockId="6.[171,388,1028,1071]" box="[171,388,1028,1071]" pageId="6" pageNumber="98">
|
|
<heading id="D0B381FEAA003131CF83C94387E11F73" bold="true" box="[171,388,1028,1071]" fontSize="14" level="1" pageId="6" pageNumber="98" reason="0">
|
|
<emphasis id="B930EA80AA003131CF83C94387E11F73" bold="true" box="[171,388,1028,1071]" pageId="6" pageNumber="98">Conclusion</emphasis>
|
|
</heading>
|
|
</paragraph>
|
|
<paragraph id="8BFB3692AA003131CDBAC941805F1D63" blockId="6.[658,1902,1025,2347]" pageId="6" pageNumber="98">
|
|
The endosteally derived bone tissues observed in this specimen of
|
|
<taxonomicName id="4C444D11AA003131C828C94185071F03" authorityName="Osborn" authorityYear="1905" class="Reptilia" family="Tyrannosauridae" genus="Tyrannosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Dinosauria" pageId="6" pageNumber="98" phylum="Chordata" rank="species" species="rex">
|
|
<emphasis id="B930EA80AA003131C828C94185071F03" italics="true" pageId="6" pageNumber="98">Tyrannosaurus rex</emphasis>
|
|
</taxonomicName>
|
|
(
|
|
<materialsCitation id="3B2C3CCFAA003131CC53C97C82521F03" ID-GBIF-Occurrence="2813104308" box="[891,1079,1083,1119]" collectionCode="MOR" pageId="6" pageNumber="98" specimenCode="MOR 1125">MOR 1125</materialsCitation>
|
|
) have all of the morphological characteristics of medullary bone, a distinctive avian reproductive tissue. Although not identical to published accounts of extant neognaths, the dinosaur tissues fall within the range of morphological variation observed in ratites. This bone tissue is derived from the endosteum, is highly vascular, and exhibits the random, woven bone arrangement consistent with very rapidly deposited bone. In addition, it has been identified on the endosteal surfaces of both femora and one tibia, the only bones examined for the presence of this tissue. The distribution is consistent with that seen in extant birds and suggests an organismal, rather than pathological, response.
|
|
</paragraph>
|
|
<caption id="DF3B661AAA003131CF85C87B845013D5" ID-DOI="http://doi.org/10.5281/zenodo.3943268" ID-Zenodo-Dep="3943268" httpUri="https://zenodo.org/record/3943268/files/figure.png" pageId="6" pageNumber="98" subCaptionStartIDs="6.[360,452,2107,2137]" subCaptionStarts="figure i" targetBox="[166,1896,168,942]" targetPageId="6">
|
|
<paragraph id="8BFB3692AA003131CF85C87B845013D5" blockId="6.[171,579,1335,2186]" pageId="6" pageNumber="98">
|
|
Figure 7.3. Demineralized fragments of medullary bone from emu
|
|
<emphasis id="B930EA80AA003131CE9BC8DB87851EE6" box="[435,480,1436,1466]" italics="true" pageId="6" pageNumber="98">(A)</emphasis>
|
|
and
|
|
<materialsCitation id="3B2C3CCFAA003131CF84C88C87311EB5" ID-GBIF-Occurrence="2813104305" box="[172,340,1483,1513]" collectionCode="MOR" pageId="6" pageNumber="98" specimenCode="MOR 1125">
|
|
MOR
|
|
<emphasis id="B930EA80AA003131CE27C88C87311EB5" box="[271,340,1483,1513]" italics="true" pageId="6" pageNumber="98">1125</emphasis>
|
|
</materialsCitation>
|
|
<emphasis id="B930EA80AA003131CE48C88C87E91EB5" box="[352,396,1483,1513]" italics="true" pageId="6" pageNumber="98">(B).</emphasis>
|
|
The fibrous, woven pattern of bone
|
|
<emphasis id="B930EA80AA003131CE21CB6C87E81D15" box="[265,397,1579,1609]" italics="true" pageId="6" pageNumber="98">matrix is</emphasis>
|
|
visible
|
|
<emphasis id="B930EA80AA003131CD2BCB6C84781D15" box="[515,541,1579,1609]" italics="true" pageId="6" pageNumber="98">in</emphasis>
|
|
both
|
|
<emphasis id="B930EA80AA003131CE2ACB1C873E1D25" box="[258,347,1627,1657]" italics="true" pageId="6" pageNumber="98">cases,</emphasis>
|
|
and the relatively lacy appearance
|
|
<emphasis id="B930EA80AA003131CF85CBFD87761D84" box="[173,275,1722,1752]" italics="true" pageId="6" pageNumber="98">results</emphasis>
|
|
from penetration of the bone by blood vessels. Scales as
|
|
<emphasis id="B930EA80AA003131CEECCA5C87601C35" italics="true" pageId="6" pageNumber="98">indicated</emphasis>
|
|
.
|
|
<emphasis id="B930EA80AA003131CE32CA0C87281C35" box="[282,333,1867,1897]" italics="true" pageId="6" pageNumber="98">For</emphasis>
|
|
methods on demineralization, see
|
|
<bibRefCitation id="EFD54B63AA003131CF85CAEC845D1C95" author="Schweitzer, M. H. & Wittmeyer, J. L. & Horner, J. R. & Toporski, J." box="[173,568,1963,1993]" journalOrPublisher="Science" pageId="6" pageNumber="98" pagination="1952 - 1955" part="307" refId="ref4648" refString="Schweitzer, M. H., Wittmeyer, J. L., and Horner, J. R., and Toporski, J. 2005 a. Soft tissue vessels and cellular preservation in Tyrannosaurus rex. Science 307: 1952 - 1955." title="Soft tissue vessels and cellular preservation in Tyrannosaurus rex" type="journal article" year="2005">
|
|
Schweitzer et al.
|
|
<emphasis id="B930EA80AA003131CEE9CAEC847E1C95" box="[449,539,1963,1993]" italics="true" pageId="6" pageNumber="98">(2005</emphasis>
|
|
a
|
|
<emphasis id="B930EA80AA003131CD05CAEC845D1C95" box="[557,568,1963,1993]" italics="true" pageId="6" pageNumber="98">)</emphasis>
|
|
</bibRefCitation>
|
|
, supplemental online
|
|
<emphasis id="B930EA80AA003131CED4CA9C87291374" italics="true" pageId="6" pageNumber="98">information</emphasis>
|
|
.
|
|
<emphasis id="B930EA80AA003131CE48C54D87FD1374" box="[352,408,2058,2088]" italics="true" pageId="6" pageNumber="98">See</emphasis>
|
|
color
|
|
<emphasis id="B930EA80AA003131CED7C54D86891305" italics="true" pageId="6" pageNumber="98">version</emphasis>
|
|
of this figure
|
|
<emphasis id="B930EA80AA003131CEF8C57C878F1305" box="[464,490,2107,2137]" italics="true" pageId="6" pageNumber="98">in</emphasis>
|
|
the accompanying CD-ROM.
|
|
</paragraph>
|
|
</caption>
|
|
<paragraph id="8BFB3692AA003131CDC8CB0882721275" blockId="6.[658,1902,1025,2347]" pageId="6" pageNumber="98">
|
|
Pathologies of the endosteum are relatively rare and localized, and they are usually accompanied bv cortical bone anomalies in the affected regions. No anomalies were observed, either grossly or microscopically, in
|
|
<materialsCitation id="3B2C3CCFAA003131CDBECBA885351C4F" ID-GBIF-Occurrence="2813104307" box="[662,848,1775,1811]" collectionCode="MOR" pageId="6" pageNumber="98" specimenCode="MOR 1125">MOR 1125</materialsCitation>
|
|
. In light of the fact that the relationship between theropod dinosaurs and birds is robustly supported (e.g.,
|
|
<bibRefCitation id="EFD54B63AA003131CAA1CA62801A1C15" author="Gauthier, J." box="[1417,1663,1829,1865]" editor="Pachan, K." journalOrPublisher="California Academv of Science Memoir" pageId="6" pageNumber="98" pagination="1 - 55" part="8" refId="ref3904" refString="Gauthier, J. 1986. Saurischian monophvlv and the origin of birds. P. 1 - 55 in Pachan, K. (ed.). The Origin of Birds and the Evolution of Flight. California Academv of Science Memoir 8." title="Saurischian monophvlv and the origin of birds" type="book" volumeTitle="The Origin of Birds and the Evolution of Flight" year="1986">Gauthier 1986</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA003131C9BCCA6281061C15" author="Sereno, P. C." box="[1684,1891,1829,1865]" journalOrPublisher="Annual Reviews of Earth and Planetary Science" pageId="6" pageNumber="98" pagination="435 - 489" part="25" refId="ref4717" refString="Sereno, P. C. 1997. The origin and evolution of dinosaurs. Annual Reviews of Earth and Planetary Science 25: 435 - 489 1997" title="The origin and evolution of dinosaurs" type="journal article" year="1997">Sereno 1997</bibRefCitation>
|
|
;
|
|
<bibRefCitation id="EFD54B63AA003131CDBECA1D85361C22" author="Holtz, T. R., Jr." box="[662,851,1882,1918]" editor="Weishainpel, D. B. & Dodson, P. & Osmalska, H." journalOrPublisher="University of California Press, Berkeley" pageId="6" pageNumber="98" pagination="111 - 136" refId="ref4021" refString="Holtz, T. R., Jr. 2004. Tyrannosauroidea. P. 111 - 136 in Weishainpel, D. B., Dodson, P., and Osmalska, H. The Dinosauria. 2 nd ed. University of California Press, Berkeley." title="Tyrannosauroidea" type="book" volumeTitle="The Dinosauria. 2 nd ed" year="2004">Holtz 2004</bibRefCitation>
|
|
), it is most parsimonious to conclude that this novel tissue seen in
|
|
<materialsCitation id="3B2C3CCFAA003131CDEDCAC885181CEF" ID-GBIF-Occurrence="2813104301" box="[709,893,1935,1971]" collectionCode="MOR" pageId="6" pageNumber="98" specimenCode="MOR 1125">MOR 1125</materialsCitation>
|
|
is medullary bone, and its presence in theropods not only adds independent support to the robustly demonstrated relationship between theropods and birds, but also suggests that these organisms had similar reproductive physiological strategies. In addition, its presence provides a means for unambiguous assignment of sex in dinosaurs. With careful examination, other, less ephemeral morphological traits may be identified in this specimen that can be applied to differentiate nonreproducing females in this lineage.
|
|
</paragraph>
|
|
</subSubSection>
|
|
</treatment>
|
|
</document> |