Fossil evidence of 'hibernation-like' state

[Still Waters]

Hibernation is a familiar feature on Earth today. Many animals—especially those that live close to or within polar regions—hibernate to get through the tough winter months when food is scarce, temperatures drop and days are dark.

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.

https://phys.org/news/2020-08-fossil-evidence-hibernation-like-state-million-year-old.html

https://www.nature.com/articles/s42003-020-01207-6