New study may solve mystery about warm-blooded dinosaurs
Scientists once thought of dinosaurs as sluggish, cold-blooded creatures. Then research suggested that some could control their body temperature, but when and how that shift came about remained a mystery.
Now, a new study estimates that the first warm-blooded dinosaurs may have roamed the Earth about 180 million years ago, about halfway through the creatures’ time on the planet.
Warm-blooded creatures — including birds, who are descended from dinosaurs, and humans — keep their body temperature constant whether the world around them runs cold or hot. Cold-blooded animals, including reptiles like snakes and lizards, depend on outside sources to control their temperature: For example, basking in the sun to warm up.
Field Museum in Chicago, said a dinosaur’s location is not the only way to determine whether it is warm-blooded. Research by Wiemann, who was not involved with the latest study, suggests that warm-blooded dinosaurs may have evolved closer to the beginning of their time on Earth, around 250 million years ago.
She said compiling clues from multiple aspects of dinosaurs’ lives — including their body temperatures and diets — may help scientists paint a clearer picture of when they evolved to be warm-blooded.
Source: cbsnews.com