Meeting Abstract

98.7  Thursday, Jan. 7  The Universal Temperature Dependence Model fails to predict body temperatures of mammals and dinosaurs LEE, A.H.*; PADIAN, K.; TAYLOR, M.T.; WEDEL, M.J.; IRMIS, R.B.; WERNING, S.; Ohio University; Univ. of California, Berkeley; University College London; Western University of Health Science; University of Utah; Univ. of California, Berkeley alee712@gmail.com

A recently published equation seemingly solved the question of dinosaur body temperature by demonstrating a pattern of increasing body temperature with size for several dinosaur species. These data suggested that extinct non-avian dinosaurs were poikilothermic and that only the largest ones could use their mass to attain homeothermy. However, that conclusion is unwarranted because the data points were incorrectly assumed to be statistically independent and a validation study of the temperature equation using extant animals was not performed. Here, we show that when phylogeny is taken into account, no significant trend exists between temperature and mass in dinosaurs. More important, we demonstrate that the temperature equation is highly inaccurate in extant mammals. In 110 of the 178 species that we analyzed, predicted and observed temperatures deviated by at least 20%. Inaccurate predictions for mammals also revealed a significant negative correlation between body temperature with size contrary to observations showing a positive trend between temperature and size. These failures stem from an assumed universal “3/4-law” in metabolic scaling, which must be rejected.