Scientists found the fossil of three new species of marsupials that were classified as the extinct species for a long time. 13 million years ago from today, a wide range of marsupials used to roam around South America. Newly discovered species are belong to the family of Palaeothentidae. The fossils will uncover much truth about little-known marsupials.
Now, a joint research team from Universidad Autónoma Tomás Frías, in Potosí, Bolivia and Case Western Reserve School of Medicine are seeking for the answer, why did these animals go extinct. In the journal of Systematic Palaeontology, researchers described that fossils of those three marsupials are the only way to learn the answer.
Lead author of the study and a biology MS student at Case Western Reserve School of Medicine, Russell Engelman said in a statement,“It was previously assumed this group slowly went extinct over a long time period, but that's probably not the case. They were doing very well at the time they were supposedly on death's door”. Those marsupial fossils were about 13 million years old and found at Quebrada Honda that is a high elevation fossil site in southern Bolivia.
Researchers identified these newly discovered marsupial species as Palaeothentes serratus, Palaeothentes relictus, and Chimeralestes ambiguous. According to Eurekalert, all of then had long snouts but their body size and diets were different. Anatomy professor Darin Croft, who was also part of the study explained that shrew opossums are the only palaeothentids that alive today.
P. Serratus had well-developed slicing premolars, as serratus means saw. That marsupial species was not more than the size of a mouse and it was weighed about 3.5 ounces. P. relictus had well-developed grinding molars and fruits, seeds and insects were their main diet. P. relictuses were slightly bigger than P. Serratus, they were around five ounces in weight. C. ambiguus had attributes of a number of family members that made its evolutionary relationships with the group uncertain. Their size was similar to P. serratus but their limited dental remains indicate their diet was likely similar to P. relictus.
