Were Dinosaurs Cold- or Warm-Blooded?: An Exercise in Scientific Inference

 

Grant Hurlburt

Tested Studies in Laboratory Teaching, 1994, Volume 15

Abstract

Both metabolic rates and brain masses are approximately 10 times as great in modern terrestrial warm-blooded animals (birds and mammals) as in cold-blooded terrestrial animals (reptiles) of the same body mass. This is one of several lines of evidence scientists have used to infer the mode of thermal regulation of dinosaurs and other extinct amniotes. In this exercise each student is assigned one of a number of dinosaurs. Students estimate brain mass from a drawing of a cranial endocast and body mass from a plastic model. They determine relative brain size and compare this to relative brain sizes of modern vertebrates. Students combine this application of allometry with information about Mesozoic environments and thermal physiology to infer the mode of thermal regulation of their assigned species.

Keywords:  allometry, relative brain size, dinosaur, thermal regulation

University of Toronto (1993)