Study Finds T. rex Had Body Temperature Similar to Humans

NEW YORK (AP) — Researchers have determined the body temperature of the Tyrannosaurus rex using fossilized teeth, finding it to be similar to that of modern humans. Previously, scientists believed dinosaurs were cold-blooded, but later evidence suggested that some were warm-blooded and could regulate their body temperature. While most scientists agree that T. rex was warm-blooded, accurately measuring the temperature of an extinct species has been challenging. Jasmina Wiemann, a paleobiologist at Johns Hopkins University, noted the difficulty in using traditional methods to ascertain this information. In a new study, researchers examined chemical clues in the teeth of T. rex, discovering that the arrangement of atoms within the enamel varies with body temperature. Co-author Aradhna Tripati, a geochemist at the University of California, Los Angeles, reported that readings from three teeth indicated an average body temperature of approximately 97 degrees Fahrenheit (36 degrees Celsius), comparable to modern elephants and close to the human average of 97 to 99 degrees Fahrenheit (36 to 37 degrees Celsius). The study was published in the journal Science Advances. Wiemann expressed surprise at the findings, suggesting that she anticipated a higher body temperature, similar to that of modern birds, which are descendants of dinosaurs. Understanding the body temperature of T. rex may provide insights into its lifestyle and habitat, as a temperature of 97 degrees would have allowed it to thrive in various climates across prehistoric North America. The research could also inform scientists about the dietary needs of T. rex to sustain its energy levels. The authors emphasized the importance of applying these methods to other dinosaur species to further explore their thermal regulation. Study co-author Robert Eagle, a geobiologist at UCLA, mentioned the potential for examining other intriguing species using this approach.