Taken from UCLA Newsroom featuring AOS’s own Robert Eagle:
https://newsroom.ucla.edu/releases/scientists-finally-know-the-body-temperature-of-the-tyrannosaurus-rex
Key takeaways
- UCLA scientists used portions of dinosaur teeth to pin down Tyrannosaurus rex’s temperature for the first time, placing it at 97 degrees Fahrenheit, comparable to a human.
- A warm-blooded T. rex would have been an energetic predator or scavenger, not a sun-basking slowpoke.
- UCLA researchers perfected the method of measuring temperature from fossils, and partnered to use T. rex teeth from the Natural History Museum of Los Angeles County.
When picturing a scaled, toothy Tyrannosaurus rex stomping across North America, building nests and eating other dinosaurs, it’s easy to forget that scientists have gleaned everything we know about T. rex from clues left more than 60 million years ago. While the presence of fossils in Alaska suggested that this prehistoric ancestor of birds was already on the evolutionary path from cold-blooded reptile to warm-blooded avian, there wasn’t a way to take T. rex’s temperature — until now.
UCLA scientists have perfected a method to measure a dinosaur’s temperature from its teeth and found that T. rex was a relatable 97 degrees Fahrenheit — almost the same as humans. The finding, using fossils from the Natural History Museum of Los Angeles County, confirms the “King of the Tyrant Lizards” would have been a fast-moving predator or scavenger — not a sun-basking slowpoke — that was able to survive in chilly climates deadly to other reptiles.
UCLA researchers developed their prehistoric thermometer method a decade ago, using bones to measure whether extinct animals were warm-blooded or cold-blooded. Testing it on a T. rex, however, required more bone than any museum would part with. Over that decade, however, the UCLA team refined the process, cutting the amount of material needed for ancient dental testing by roughly 90%. It was enough to convince LA’s Natural History Museum to provide portions of two teeth from Thomas the T. rex, the most complete of the towering tyrannosaur skeletons inside the museum’s dinosaur hall.
Though scientists have found increasing evidence that T. rex was warm-blooded in recent years, the study published Sept. 16 in Science Advances marks the first time scientists have an actual number.
“No one’s been able to make a temperature measurement like this before,” UCLA geobiologist and study co-author Robert Eagle said. “We found T. rex was 36 Celsius (97 Fahrenheit), about the same as humans. The temperature is about what I would have guessed — higher than a reptile or a slow mammal like a sloth, but lower than an avian.”
Though still a scaly, egg-laying reptile, T. rex’s 36 C body temperature is comparable to a furry, warm-blooded mammal’s. Modern, cold-blooded reptiles run about 28–30 C (82–86 F), while most birds — T. rex’s evolutionary descendants — often run much warmer at 40–43 C (104–109 F), Eagle said.
Continue reading on UCLA Newsroom:
https://newsroom.ucla.edu/releases/scientists-finally-know-the-body-temperature-of-the-tyrannosaurus-rex