Study Suggests Hibernation Was An Ancient Adaptation To Harsh Winters

The image seen below is an illustration of a creature called a Lystrosaurus. The strange-looking creature had claws on its digits, a beak reminiscent of a turtle, and a pair of tusks. Scientists believe that the creature was able to survive the harsh winters in Antarctica by hibernating.The researchers believe that this could be the oldest animal on record to hibernate rather than attempt fruitlessly to find food during harsh winter months. Scientists analyzed the creature's tusks, which grew continuously. That analysis suggests that the creature may have spent part of the year in hibernation.

Modern animals, such as bears and others, still hibernate to help them through long winter months when food is scarce. During hibernation, the extinct creature the researchers are studying was able to slow down its metabolism and go through periods of minimal activity when conditions are rough.

Preliminary findings in the new study suggests that hibernation is not a relatively new adaptation, rather it's an ancient one. This particular genus of creatures was able to survive the Permian Mass Extinction, which was the planet's largest mass extinction that occurred about 252 million years ago and killed 70 percent of land vertebrates. Lysotrosaurus fossils have been discovered in India, China, Russia, Africa, and Antarctica.

These creatures are ancient relatives to mammals and can grow up to eight feet long. The researchers compared cross-sections of tusks from six Antarctic Lystrosaurus and four from South Africa during the study. The team found that the tusks from both regions had similar growth patterns made up of concentric circles of dentine, which is a hard and dense bony tissue.

However, scientists noted that the tusks fossils from Antarctica had some thick closely-space rings while the fossils from South Africa did not. The thicker rings represent less dentine deposition and suggests that the animals went through periods of prolonged stress. The closest analog scientists can find e similar stress marks and teeth associated hibernation in certain modern animals.