Dinosaurs were warm-blooded, according to a scientist who judged their metabolism using body mass and growth rates deduced from fossils of species including Tyrannosaurus rex.
Paleontologist Michael D'Emic of Stony Brook University in New York took issue with the conclusion of other researchers last year that dinosaurs were neither cold-blooded nor warm-blooded, but had a metabolism somewhere in between.
Scientists have debated since the 19th century whether dinosaurs were slow, lumbering, cold-blooded creatures, as originally thought, or boasted a more warm-blooded physiology allowing for a vigorous lifestyle.