Fossil of New Mammal Species From Dinosaur Era Found in Mongolia’s Gobi Desert

Fossil jaw of Ravjaa ishiii from Mongolia’s Bayanshiree Formation. Credit: Tsukasa Okoshi et al.

A technological squad discovered a antecedently chartless taxon of tiny mammal successful the Gobi Desert of Mongolia. The carnal lived during the Late Cretaceous period, erstwhile dinosaurs inactive roamed the Earth.

The fossil, which includes portion of a little jaw measuring conscionable 1 centimeter, was recovered successful 2019 during a associated expedition to the Baynshire Formation. The site, affluent successful past stone layers, lies heavy successful the Gobi Desert and dates backmost implicit 66 cardinal years.

Fossil named successful grant of a monk and depository director

The caller species, which the squad calls Ravjaa ishiii, honors 2 individuals who played cardinal roles successful the region’s past and science. The first, Danzanravjaa, was a respected Buddhist monk from the 19th century.

The second, Kenichi Ishii, was the precocious manager of Japan’s Hayashibara Museum of Natural Sciences and helped physique the Mongolia-Japan probe concern that led to this discovery.

The findings were published successful the diary Acta Palaeontologica Polonica. Researchers from Okayama University of Science successful Japan and the Mongolian Academy of Sciences collaborated connected the study.

Fossil suggests wider scope for past mammal group

The archetypal investigation showed that the fossil belonged to a radical of past mammals called zhelestids. These animals were erstwhile believed to unrecorded chiefly adjacent past coastlines. However, this discovery, recovered heavy inland, suggests they had a overmuch wider range.

3D scan of Ravjaa ishiii jaw fossil shows bony operation and interior features. Credit: Tsukasa Okoshi

The fossil stood retired due to the fact that of its antithetic features. Its molars were taller than immoderate different taxon it was related to, and the jaw had a distinctive shape. These differences led scientists to state it a caller genus and species.

Teeth hint astatine aboriginal plant-based fare successful mammals

The squad besides noted the value of the site’s age. The Baynshire Formation’s rocks day to a play erstwhile flowering plants were becoming common.

The beardown teeth of Ravjaa ishiii suggest it whitethorn person eaten seeds oregon fruits, giving researchers a hint that aboriginal mammals were already adapting to changing works life.

Researchers telephone the find a uncommon and fortunate find

Tsukasa Okoshi, pb writer of the survey and a doctoral pupil astatine Okayama University of Science, said the pandemic delayed the research. But the squad remained committed.

“We were yet capable to found the technological value of this specimen,” Okoshi said.

“We anticipation this probe volition service arsenic a starting constituent for further taxonomic studies of different tiny vertebrate fossils from the aforesaid tract and epoch and volition yet assistance uncover the affluent biodiversity, including dinosaurs, that erstwhile inhabited the Gobi Desert during the property of dinosaurs.”

Professor Mototaka Saneyoshi, who besides worked connected the project, called the find remarkable. “Finding specified a tiny fossil successful the immense expanse of the Gobi Desert feels similar a acquisition from the Gobi Desert. It’s thing abbreviated of miraculous.”

The find adds to the increasing database of ancient mammal taxon successful Mongolia and helps scientists amended recognize however beingness connected Earth changed during the last property of the dinosaurs.