T. rex Ran a Human-Like 97°F, Fossil Teeth Reveal Warm-Blooded Metabolism
A team of researchers has established that the body temperature of Tyrannosaurus rex was approximately 97 degrees Fahrenheit, akin to that of modern humans. This conclusion was reached by drilling small holes in fossilized teeth and examining the chemical bonds in the enamel. The findings, published on September 16 in Science Advances, focused on three teeth from a remarkably complete T. rex skeleton named Thomas. Co-author Aradhna Tripati from UCLA remarked on the limited knowledge surrounding T. rex's metabolism. The study also highlighted a distinction between T. rex and an ancient crocodilian, which had a cooler body temperature of 88 degrees. The elevated metabolic rates indicate that T. rex required more sustenance and could have thrived in cooler climates, suggesting it might have inhabited regions as far as Mexico, altering perceptions of its habitat preferences.
Key facts
- Tyrannosaurus rex had a body temperature of 97 degrees Fahrenheit, similar to modern humans.
- The study was published September 16 in the journal Science Advances.
- Researchers analyzed three fossilized dinosaur teeth from the Natural History Museum of Los Angeles County, two from a T. rex named Thomas.
- The method measured chemical bonds between carbon and oxygen in tooth enamel; bond numbers increase as temperature decreases.
- An ancient crocodilian from the same Montana site had a cooler body temperature of 88 degrees, based on five teeth.
- T. rex’s temperature was above today’s reptiles (82–86°F) and below living birds (104–109°F).
- Paleoclimate simulations indicated T. rex could have lived as far south as Mexico.
- Alaska has produced tyrannosaurid fossils but no Cretaceous reptile fossils, suggesting cold-blooded dinosaurs could not survive there.
Entities
Artists
- Aradhna Tripati
- Robert Eagle
- Alfio Alessandro Chiarenza
- Jasmina Wiemann
- Thomas
Institutions
- University of California, Los Angeles
- Natural History Museum of Los Angeles County
- University College London
- Johns Hopkins University
- Science Advances
- CNN
- Scientific American
- Reuters
- New York Times
Locations
- Los Angeles
- United States
- Montana
- Alaska
- Mexico
- London
- United Kingdom
- Baltimore
- Maryland