In a new study, by the University of Washington, it was found that an animal that survived a mass extinction about 250 billion years ago appears to have slipped into a hibernation-like state to cope with the harsh winter conditions in Antarctica. These suggest that the adaptation – seen in some modern animals – could date back to prehistoric times.
The animal is Lystrosaurus which exist from the prehistoric time and can be related to the mammal family. They roamed the Earth 250M years ago in the Early Triassic period and existed even before dinosaurs arrived at the scene. Thereby, it is has been found that the Lystrosaurus has been crossed many times period that are Triassic, Jurassic, Cretaceous.
Body And Nature of Lystrosaurus
These creatures were stubby and roughly pig-sized. However, some grew up to 6 to 8 feet. They had no teeth but had tusks in the upper jaw to support foraging.
In the study, it was also found that tusks, which like elephants, grow with age. The fossilized tusks hold records on the animal’s life-history, including metabolism, growth, and stress or strain. In the cross-section of the tusks, the team specifically looked at dentine, which is deposited as concentric circles. Dentine is a bony tissue present in human teeth as well, under the enamel.
The thin-section of the fossilized tusk from an Antarctic Lystrosaurus shows layers of dentine deposited in rings of growth. At the top right is a close-up view of the layers, with a white bar highlighting a zone indicative of a hibernation-like state.
What happens when they go for hibernating? When animals hibernate, they go into a deep-sleep state, they slow their breathing rates and lower their body temperatures. This adaptation allows them to stay put for days or even weeks, without having to need water and food. It helps them survive the cold and food scarcity.
Where were they found? These creatures survived the Permian mass extinction, which wiped out 90% of the world’s species, including 70% of the vertebrates. Lystrosaurus likely spread across the world, from Russia to Antarctica. Whitney, who conducted this study as a doctoral student at the University of Washington (UW) examined and compared six Lystrosaurus fossils found in Antarctica with four in South Africa.
The analysis showed that the tusks of Antarctic Lystrosaurus and their South African counterparts showed similar growth patterns. But one difference stood out: the Antarctic fossils had closely-spaced, thick rings. This feature suggests less dentine deposition, which could be the result of prolonged stress associated with hibernation, according to the researchers.
However, with the study researchers are not sure whether the animal went through true hibernation. Instead, they think the animal may have gone into a hibernation-like state, involving a more short-term reduction in metabolism.