Paleontologists Have Discovered Two Species Of Mammals That Outlive The Dinosaurs By 25 Million Years
Scientists from Russia and Germany have described two previously unknown species of herbivorous mammals that survived their contemporaries, the dinosaurs, by 25 million years. The authors of the study concluded that these mammals spread around the world from the territory of modern Siberia, the press service of the Borisyak Paleontological Institute of the Russian Academy of Sciences reported on Wednesday.
"A team of paleontologists from Moscow, Saint Petersburg, Tomsk, Sharypov, and Bonn has compiled a description of two previously unknown species of ancient multituberculates. The remains of these extinct herbivorous mammals, which appeared in the middle of the Jurassic period and survived the dinosaurs by 25 million years, were discovered in Siberia. These species were named "Tashtykia early"(Tashtykia Primaeva) and" Theory ancient" (Tagaria Antiqua) - after the names of the Tashtyk and Tagar archaeological cultures in southern Siberia," the report says. The results are published in the scientific journal Papers in Palaeontology.
"Tashtykiya had a characteristic multituberculate posterior lower pre-root tooth-blade, similar to the half of the serrated disk of a circular saw. The smaller Tagaria differed from the other multituberculates by an unusually long posterior upper pre-root tooth with a very large number of tubercles - it has 17 of them. Due to the open diversity of the middle Jurassic multituberculates, it can be assumed that the territory of Siberia was the center of origin of this group," the press service quotes the words of scientists.
Multituberculates numbered more than 20 families and lived on all continents. They had multituberculate molars, and the tubercles on them were arranged in two longitudinal rows so that when closed, the outer row of tubercles on the lower teeth entered the space between the rows on the upper ones. Most multituberculates were land animals, some were good jumpers, and many later forms were arboreal. In appearance, they resembled rodents the size of a mouse to a beaver, but they were not closely related to them, as they belonged to a separate branch of mammals.
Little is known about the origin of poly bugs, but the main hypothesis suggests that they are related to the Jurassic group eucharamiidae. Many representatives of the latter had a flying membrane and could, like modern flying squirrels, plan from tree to tree. Fossilized remains of these small animals, which ate seeds and shoots of ferns and gymnosperms, are found in abundance in the middle Jurassic deposits of China, and in Russia, they were found in the Berezovsky quarry near the city of Sharypovo in the Krasnoyarsk territory.