Mammals that lived during the time of the dinosaurs are often portrayed as innocuous, small-bodied creatures, scurrying under the feet of the huge reptiles. In reality, this wasn’t the case, and a new fossil from Madagascar further underscores this point, revealing fascinating perspectives on the growing diversity of Mesozoic mammals. Vintana is a member of an extinct and until now very poorly known group of mammals, the gondwanatherians, which are named based on their geographic distribution on the southern continents, also known as Gondwana. Previously known fossils of gondwanatherians had consisted only of isolated teeth and a few fragmentary lower jaw specimens. The new specimen is a nearly complete and only slightly distorted cranium, which was painstakingly removed from a large block of sediment and later micro-CT scanned to provide fine details of both the external and internal anatomy of the animal. These scans also allowed the investigators to digitally separate, or segment, individual cranial bones and allowed them to virtually dissect the specimen without actually destroying it. The cranium displays some bizarre features, like enlarged flanges for attachment of chewing muscles, a strangely tilted braincase, and large eye sockets. Analysis of these features and others reveals that Vintana was a badger-sized, herbivorous animal that was agile and active, with keen senses of smell, vision, and hearing.
