Regulation of body temperature by some Mesozoic marine reptiles.
What the body temperature and thermoregulation processes of extinct vertebrates were are central questions for understanding their ecology and evolution. The thermophysiologic status of the great marine reptiles is still unknown, even though some studies have suggested that thermoregulation may have contributed to their exceptional evolutionary success as apex predators of Mesozoic aquatic ecosystems. We tested the thermal status of ichthyosaurs, plesiosaurs, and mosasaurs by comparing the oxygen isotope compositions of their tooth phosphate to those of coexisting fish. Data distribution reveals that these large marine reptiles were able to maintain a constant and high body temperature in oceanic environments ranging from tropical to cold temperate. Their estimated body temperatures, in the range from 35 degrees +/- 2 degrees C to 39 degrees +/- 2 degrees C, suggest high metabolic rates required for predation and fast swimming over large distances offshore.
CNRS UMR 5125, Paléoenvironnements et Paléobiosphère, Université Lyon 1, Lyon, 2 Rue Raphaël Dubois, 69622 Villeurbanne Cedex, France.
Aurélien
A
Bernard
Christophe
C
Lécuyer
Peggy
P
Vincent
Romain
R
Amiot
Nathalie
N
Bardet
Eric
E
Buffetaut
Gilles
G
Cuny
François
F
Fourel
François
F
Martineau
Jean-Michel
JM
Mazin
Abel
A
Prieur
D000222:Adaptation, Physiological; D000818:Animals; D005075:Biological Evolution; D001831:Body Temperature; D001833:Body Temperature Regulation; D053476:Extinction, Biological; D005399:Fishes; D005580:Fossils; D019015:Geologic Sediments; D009792:Oceans and Seas; D010103:Oxygen Isotopes / Q000032:analysis; D010161:Paleodontology; D010710:Phosphates / Q000737:chemistry; D011235:Predatory Behavior; D012104:Reptiles / Q000033:anatomy & histology / Q000502:physiology*; D012623:Seawater; D013550:Swimming; D013696:Temperature; D014070:Tooth / Q000737:chemistry
D010103:Oxygen Isotopes; D010710:Phosphates