Tyrannosaurus rex was warm-blooded, new study confirms

A study in Science Advances confirmed that the internal temperature of Tyrannosaurus rex was about 97 °F (36 °C), similar to modern warm-blooded humans. The method analyzing carbon and oxygen isotope bonds in tooth enamel reduced the required sample size by 90%.

• T. rex body temperature was about 97 °F (36 °C), higher than modern reptiles and sloths
• Analysis required only a few milligrams of enamel from two teeth from the Natural History Museum of Los Angeles County
• Warm-bloodedness explains how T. rex lived in cold regions, including what is now Alaska
• Method was previously used to confirm warm-bloodedness in megalodon