Pareiasaurs were large herbivores that flourished during the Permian period, before the dinosaurs roamed the planet, according to a new research.
These anapsid reptiles, in the family Pareiasauridae, had bony knobs on their bodies and skull, small heads, and stumpy legs, according to a new study.
In the study – published on Friday (Feb. 19) in the online Zoological Journal of the Linnean Society – the researchers found that pareiasaurs lived about 266 to 252 million years ago. Their bodies were covered in bony armour to help protect them from various sharp-toothed predators. They usually ranged in size from about seven to almost ten feet (two to three m) long and weighed up to 1,300 pounds (six hundred kg).
Pareiasaurs were stocky, they broad feet, robust limbs, and a short tail. Their skulls were ornamented with various ridges and knobs, the researchers said. Pareiasaurs’ time on Earth was relatively short, ending after just ten million years during the Permian mass extinction, also known as the End Permian or the Great Permian Extinction (occurred about 253 million years ago). Scientists say that the extinction wiped out about ninety percent of all species living at that time.
These herbivorous reptiles lived in similar environments to modern-day mammals, the researchers said. They probably enjoyed tropical area with a lot of vegetation, and give that most of the Earth had such climate at that time, their range was likely quite vast, the researchers explained.
Michael Benton, a vertebrate palaeontologist at the University of Bristol, said that although the stocky herbivores are less well-known than their successors (dinosaurs), represent the peak of the evolution of vertebrates on land. They have also been called the ugliest fossil reptiles, according to Dr. Benton.
Fossils of pareiasaurs have been found mostly in Russia (making up fifty-two percent of all the tetrapod fossils) and South Africa, but also in some places from Europe, China, and South America.
The specimens unearthed in China were thought to represent six different species, Dr. Benton said. After analysing them in detail, Benton found that there were in fact only tree species of pareiasaurs.
Linda Tsuji, curator of natural history at the Royal Ontario Museum, stated that the new findings can be used to better understand how pareiasaurs managed to colonise various parts of the world and how they migrated.
During the Permian period, Earth still had one supercontinent known as Pangea, which is why it is not that surprising that the fossils of the stocky herbivores were found in present-day Russia, China, South Africa, Europe, and South America, according to Dr. Benton.
Dr. Tsuji said that the study is very important because it sheds some light on the evolution of pareiasaurs, since they are a relatively poorly understood group.
Benton stated that the event that wiped out the pareiasaurs was quite sudden and did not occur over a long period of time, slowly leading the animals to extinction. However, something good came out of this extinction: the Earth was cleared for the ancestors of today’s animals to emerge. Dinosaurs eventually gave rise to birds, and mammals first appeared about 200 million years ago, Dr. Benton explained.
Image Source: my science