ABOVE: An artist’s depiction of a heatmap showing smaller dinosaurs’ increased ability to generate heat
MAURICIO ALVAREZ
How did dinosaurs evolve into warm-blooded birds? It may be related to an increase in metabolic rates as dinos’ body size decreased, according to a study published yesterday (January 1) in Science Advances.
Birds are endothermic, or warm-blooded, animals—they can regulate their own body temperature. Dinosaurs, on the other hand, didn’t have as much of an ability to control their body temperature as modern-day birds and mammals do. While they weren’t fully ectothermic, or cold-blooded, they still had to partially rely on the environment by sunning or shading themselves to adjust their internal temperature.
Enrico Rezende, an ecologist at the Pontifical Catholic University of Chile, and colleagues wanted to learn more about the transition to endothermy. The team calculated the metabolic rates of theropods, a group of dinosaurs that evolved into birds, by combining ...
