Fossil evidence of 'hibernation-like' state in 250-million-year-old Antarctic animal.
According to new research, this type of adaptation has a long history. In a paper published Aug. 27 in the journal Communications Biology , scientists at the University of Washington and its Burke Museum of Natural History and Culture report evidence of a hibernation-like state in an animal that lived in Antarctica during the Early Triassic, some 250 million years ago. The creature a member of the genus Lystrosaurus, was a distant relative of mammals. Antarctica during Lystrosaurus' time lay largely within the Antarctic Circle, like today, and experienced extended periods without sunlight each winter. The fossils are the oldest evidence of a hibernation-like state in a vertebrate animal , and indicates that torpor—a general term for hibernation and similar states in which animals temporarily lower their metabolic rate to get through a tough season—arose in vertebrates even before mammals and dinosaurs evolved. "Animals that live at or near the...