Scientists measure extinct species' temps

GAINESVILLE, Fla., May 26 (UPI) -- U.S. scientists say they have found a way to measure the body temperatures of extinct vertebrates and reconstruct the temperatures of ancient environments.

The study describes how scientists could use carbon and oxygen isotopes from fossils to more accurately determine whether extinct animals were warm-blooded or cold-blooded and better estimate temperature ranges during the times the animals lived.

"The method described in the study has been shown to work with 12-million-year-old fossils from Florida and the next step is to look at even older fossils," said study co-author Richard Hulbert, a vertebrate paleontologist at the Florida Museum of Natural History at the University of Florida.

The new "clumped-isotope" paleothermometer method used in the study analyzes two rare heavy isotopes, carbon-13 and oxygen-18, found in tooth enamel, bones and eggshells.

"Clumping is temperature dependent, so at low temperatures you get more clumping together in a mineral while high temperatures mean less clumping," said California Institute of Technology postdoctoral scholar Robert Eagle, the study's lead author. "If you can measure the clumping accurately enough, you can work out the temperature at which a mineral formed. In the case of teeth and bone, this will be the body temperature of the organism."

The research that included John Eiler, Aradhna Tripati, Edwin Schauble and Thomas Tutken appears in the early online edition of the Proceedings of the National Academy of Sciences.