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Our results show that\n                    <jats:italic>O. megalodon<\/jats:italic>\n                    had an overall warmer body temperature compared with its ambient environment and other coexisting shark species, providing quantitative and experimental support for recent biophysical modeling studies that suggest endothermy was one of the key drivers for gigantism in\n                    <jats:italic>O. megalodon<\/jats:italic>\n                    and other lamniform sharks. The gigantic body size with high metabolic costs of having high body temperatures may have contributed to the vulnerability of\n                    <jats:italic>Otodus<\/jats:italic>\n                    species to extinction when compared to other sympatric sharks that survived the Pliocene epoch.\n                  <\/jats:p>","DOI":"10.1073\/pnas.2218153120","type":"journal-article","created":{"date-parts":[[2023,6,26]],"date-time":"2023-06-26T15:09:49Z","timestamp":1687792189000},"update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":27,"title":["Endothermic physiology of extinct megatooth sharks"],"prefix":"10.1073","volume":"120","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4051-7568","authenticated-orcid":false,"given":"Michael L.","family":"Griffiths","sequence":"first","affiliation":[{"name":"Department of Environmental Science, William Paterson University of New Jersey, Wayne, NJ 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