The findings, published in Science Advances, offer the first direct numerical estimate of the dinosaur’s internal temperature. Because they were classified as reptiles, for years, dinosaurs were generally thought to be cold-blooded animals. Researchers at the University of California, Los Angeles (UCLA) estimate that T. rex had a body temperature of around 36°C (97°F), close to that of humans.
But a new study suggests that one of the most famous dinosaurs, Tyrannosaurus rex, may have been much warmer than previously believed.
Scientists examined the chemical makeup of the dinosaur’s tooth enamel. Certain carbon and oxygen isotopes form bonds that are influenced by temperature, allowing researchers to use the fossilised enamel as a kind of ancient thermometer. Researchers say knowing the dinosaur’s approximate body temperature could also help scientists understand its behaviour, energy needs and interactions with other species millions of years ago. So far, the technique has been used on a handful of ancient species, including other dinosaurs, woolly mammoths and megalodons.
“No one’s been able to make a temperature measurement like this before,” Robert Eagle, a study co-author and geobiologist at the University of California Los Angeles (UCLA), said in a statement. “Tooth enamel forms inside the animal at body temperature, so the enamel chemistry is a thermometer,” said UCLA geoscientist Aradhna Tripati. “This was a warm-bodied organism, which really places new constraints on its behaviour, its physiology, how it interacted with other species and how much food it needed, for example,” said Robert Eagle.
