Scientists have debated for a long time about whether some dinosaurs were warm-blooded. Recently, researchers claim they have utilized chemistry to determine the body temperature of two T. rexes.
Aradhna Tripati, a professor and geochemist at the University of California, Los Angeles, admitted that it was a challenging task. She co-authored a study published in the journal Science Advances and discussed the process with CBC’s Quirks & Quarks before an interview with host Bob McDonald.
In order to measure the temperature of extinct animals, scientists employed a method based on the chemical composition of hard tissues like tooth enamel and eggshells. These tissues contain a mineral called bioapatite, where carbon atoms bond with oxygen. By analyzing the “isotope clumping” in living animals with different body temperatures, researchers could estimate the body temperature of dinosaurs.
A decade ago, UCLA scientists examined eggshells from titanosaurs and oviraptors, concluding that they were warm-blooded. They also studied teeth from herbivorous dinosaurs like brachiosaurs, known for their thick enamel.
Analyzing the thin tooth enamel of tyrannosaurs like T. rex was challenging. The researchers practiced the technique using teeth from the megalodon until they could successfully analyze small samples. They obtained tooth enamel samples from Thomas the T. rex, estimating its body temperature to be between 33.8°C and 38.8°C, similar to large mammals and possibly flightless birds like ostriches.
Tripati explained that an animal’s body temperature influences its behavior and habitat range. The warm-blooded nature of T. rex would have allowed it to inhabit various environments, including the Arctic, unlike cold-blooded reptiles.
Paleontologist Anthony Fiorillo, who described a small tyrannosaur in Alaska, praised the study’s findings, suggesting that it sheds light on dinosaur adaptation to northern climates. François Therrien, a curator at the Royal Tyrrell Museum, used isotope clumping to reveal the warm-blooded nature of troodons, indicating body temperatures exceeding 40°C.
Therrien emphasized that T. rex’s warm body temperature enabled it to be active day and night throughout the year, explaining its wide range from Mexico to Alaska. However, the extent of T. rex’s warm-blooded metabolism compared to modern mammals and birds remains a topic of debate.
