Archaeologists unearth fossil of unknown dinosaur-era mammal in Mongolian desert

Just when you thought that we have discovered all the ancient species that roamed the Earth before us, archaeologists make another shocking discovery, the most recent case being a previously unknown dinosaur-era mammal unearthed in Mongolia’s Gobi Desert.

As it happens, a research team has uncovered a fossil belonging to a new genus and species of mammal in the Late Cretaceous (the epoch from 100-66 million years ago) strata of the Mongolian desert, according to a Phys.org report published on April 29.

Per the study in the journal Acta Palaeontologica Polonica, the researchers named the mouse-sized animal Ravjaa Ishii, thus honoring Dulduityn Danzanravjaa, a revered 19th-century Buddhist monk, and the late Kenichi Ishii, the former director of the Hayashibara Museum of Natural Sciences, who helped establish the research partnership.

Discovering the dinosaur-era mammal

Indeed, the team that made the discovery included experts from Okayama University of Science (OUS) and the Institute of Paleontology and Geology at the Mongolian Academy of Sciences (IPMAS), who found a one-centimeter partial lower jaw during a 2019 expedition to the Bayanshiree Formation, the fossil-bearing deposit in the Gobi Desert.

The subsequent analysis revealed that it belonged to a member of a Cretaceous mammal family called Zhelestidae, but its unusually tall molars and distinctive jaw shape were unlike those of its known relatives, leading to the establishment of a new genus and species.

Commenting on the breakthrough, Tsukasa Okoshi, the lead author of the study and an OUS doctoral candidate, explained that the COVID-19 pandemic impeded the publication process, but that now the scientists were finally able to determine the scientific importance of the discovery. As he added:

“We hope this research will serve as a starting point for further taxonomic studies of other small vertebrate fossils from the same site and era and will ultimately help uncover the rich biodiversity – including dinosaurs – that once inhabited the Gobi Desert during the age of dinosaurs.”

Elsewhere, researchers have made other important discoveries in the field of mammalian fauna, as they recently identified Tunisia as the most likely origin of domestic cats, challenging the previous findings according to which they hailed from Europe.