Dinosaur Body Temperatures Determined from Isotopic (13C-18O) Ordering in Fossil Biominerals

  title={Dinosaur Body Temperatures Determined from Isotopic (13C-18O) Ordering in Fossil Biominerals},
  author={Robert A. Eagle and Thomas T{\"u}tken and Taylor S. Martin and A. Tripati and Henry C. Fricke and Melissa V. Connely and Richard. Cifelli and John Eiler},
  pages={443 - 445}
Large dinosaurs had body temperatures similar to those of modern mammals and birds. The nature of the physiology and thermal regulation of the nonavian dinosaurs is the subject of debate. Previously, arguments have been made for both endothermic and ectothermic metabolisms on the basis of differing methodologies. We used clumped isotope thermometry to determine body temperatures from the fossilized teeth of large Jurassic sauropods. Our data indicate body temperatures of 36° to 38°C, which are… 
Isotopic ordering in eggshells reflects body temperatures and suggests differing thermophysiology in two Cretaceous dinosaurs.
Clumped isotope analysis of eggshells can be used to determine body temperatures of females during periods of ovulation and indicates that variable thermoregulation likely existed among the non-avian dinosaurs and that not all dinosaurs had body temperatures in the range of that seen in modern birds.
Eggshell geochemistry reveals ancestral metabolic thermoregulation in Dinosauria
Applying this method to well-preserved fossil eggshells demonstrates that the three major clades of dinosaurs, Ornithischia, Sauropodomorpha, and Theropoda, were characterized by warm body temperatures, and that metabolically controlled thermoregulation was the ancestral condition for Dinosauria.
Paleoclimate Implications from Stable Isotope Analysis of Sedimentary Organic Carbon and Vertebrate Fossils from the Cedar Mountain Formation, UT, U.S.A.
Oxygen and carbon isotopic compositions of fossilized vertebrate teeth and bone were analyzed to determine isotopic values of vertebrate faunal diet from the early Cretaceous Cedar Mountain Formation
The evolution of mammalian body temperature: the Cenozoic supraendothermic pulses
  • B. Lovegrove
  • Biology, Geography
    Journal of Comparative Physiology B
  • 2011
It is anticipated that the method of estimating body temperature from the abundance of 13C–18O bonds in the carbonate component of tooth bioapatite in both extant and extinct animals may be a very promising tool for estimating the Tb of extinct mammals.
The influence of temperature and seawater carbonate saturation state on 13C–18O bond ordering in bivalve mollusks
The shells of marine mollusks are widely used archives of past climate and ocean chemistry. Whilst the measurement of mollusk δ18O to develop records of past climate change is a commonly used
Do paleontologists dream of electric dinosaurs? Investigating the presumed inefficiency of dinosaurs contact incubating partially buried eggs
Results from this experiment provide evidence for a possible evolutionary path from guarding behavior to thermoregulatory contact incubation in Troodon formosus, and show that contact incubating partially buried eggs did seem to confer an energetic advantage.


Thermophysiology of Tyrannosaurus rex: Evidence from Oxygen Isotopes
Values of δp from a well-preserved Tyrannosaurus rex suggest that this species maintained homeothermy with less than 4�C of variability in body temperature, which implies a relatively high metabolic rate that is similar to that of endotherms.
Multiple taxon multiple locality approach to providing oxygen isotope evidence for warm-blooded theropod dinosaurs
Oxygen isotope ratios of fossil remains of coexisting taxa from several different localities can be used to help investigate dinosaur thermoregulation, and inferred homoethermy in theropods is likely due to higher rates of metabolic heat production relative to crocodiles.
Dinosaur body temperatures: the occurrence of endothermy and ectothermy
  • F. Seebacher
  • Environmental Science, Geography
  • 2003
The commonly asked question whether dinosaurs were ectotherms or endotherms is inappropriate, and it is more constructive to ask which dinosaurs were likely to have been endothermic and which ones ectothermic, which suggests endothermy most likely evolved among the Coelurosauria and, to a lesser extent, among the Hypsilophodontidae.
Body temperatures of modern and extinct vertebrates from 13C-18O bond abundances in bioapatite
It is shown that the abundance of 13C-18O bonds in the carbonate component of tooth bioapatite from modern specimens decreases with increasing body temperature of the animal, following a relationship between isotope “clumping” and temperature that is statistically indistinguishable from inorganic calcite.
Biophysical constraints on the thermal ecology of dinosaurs
A model-based approach to body temperatures in dinosaurs allows us to predict what ranges of body temperatures and what thermoregulatory strategies were available to those dinosaurs and suggests that endothermic metabolism and metabolic heating might have been useful for intermediate and large-sized dinosaurs but often in situations that demanded marked seasonal adjustment of metabolic rates and/or precise control of metabolism.
Metabolism of leatherback turtles, gigantothermy, and thermoregulation of dinosaurs
It is indicated that leatherbacks can use large body size, peripheral tissues as insulation, and circulatory changes, to maintain warm temperatures in the North Atlantic and to avoid overheating in the tropics.
Biology of the sauropod dinosaurs: the evolution of gigantism
There is no evidence, however, that resource availability and global physicochemical parameters were different enough in the Mesozoic to have led to sauropod gigantism.
Crocodiles as dinosaurs: behavioural thermoregulation in very large ectotherms leads to high and stable body temperatures
The study confirms that, in low latitudes at least, large dinosaurs must have had an essentially high and stable value of Tb, without any need for endothermy, and the finding of increasing 'average' Tb as ectotherms grow larger may have implications for the metabolic rates of very large reptiles.