Study Estimates Body Temperature of Tyrannosaurus rex

Chemical analysis of a fossilized tooth from the Tyrannosaurus rex, known as Thomas, has provided an estimate of the dinosaur's body temperature, suggesting it was around 97.3 degrees Fahrenheit, plus or minus 4.5 degrees. This research, published in the journal Science Advances, indicates that T. rex and similar theropods were warm-blooded, contrasting with cold-blooded reptiles. Co-author Robert Eagle, an associate professor at UCLA’s Institute of the Environment and Sustainability, noted the significance of being able to measure body temperature directly, which had not been possible before. The study analyzed carbon and oxygen isotopes in the fossil, with fewer bonds indicating higher formation temperatures. The findings suggest that T. rex's body temperature was suitable for life across North America during the Cretaceous Period. Eagle's team plans further analysis on the tooth before returning it to the museum's collection. The Natural History Museum of Los Angeles County excavated about 70% of Thomas's skeleton in the early 2000s, making it one of the most complete T. rex specimens discovered. Luis Chiappe, director of the Dinosaur Institute at the museum, emphasized the value of natural history collections for unexpected scientific insights.