Dinosaurs, Like Mammals Were Warm-Blooded
They are often portrayed as cold-blooded killers but re-analysis of a previous study suggests dinosaurs like other mammals, were warm-blooded after all.
Michael D'Emic a palaeontologist at Stony Brooke University, who specializes in studying bone, has suggested that dinosaurs were not an intermediate between the warm and cold blooded creatures as the original study published in 2014 had suggested. Instead they can be clearly categorized as warm-blooded. The strongest argument for this suggestion comes from the pattern of growth the original considered.
"Many animals do not grow continuously throughout the year, generally slowing or pausing growth during colder, drier, or otherwise more stressful seasons. Therefore, the previous study underestimated dinosaur growth rates by failing to account for their uneven growth. Like most animals, dinosaurs slowed or paused their growth annually, as shown by rings in their bones analogous to tree rings," he explained.
The previous study had scaled yearly growth rates to daily growth rates and had reportedly underestimated growth rates for large animals like dinosaurs which lived in stressful and seasonal environments.
Dr. D'Emic has also argued that dinosaurs should be statistically analyzed within the same group as birds, which are also warm-blooded and are descendents of dinosaurs.
The re-analysis could change the way scientists understand the development and evolution of dinosaurs.
"D'Emic's study reveals how important access to the data behind published results is for hypothesis testing and advancing our understanding of dinosaur growth dynamics," said Holly Woodward, Assistant Professor at Oklahoma State University.