09 July 2012
Posted in DinoDigs
In 2002, paleontologists found the second-oldest mammal skull just outside of a rural village in northern Argentina. At the time, the skull was mostly hidden in rock and its identity remained a mystery. In 2005, scientists sent the skull to a technician who, until recently, has been removing the rock from around the fossil – finally revealing a saber-toothed, squirrel-like creature with a striking similarity to the Ice Age character Scrat. The new species, named Cronopio dentiacutus for its narrow snout and long fangs, was about 8 to 9 inches (20 to 23 centimeters) long and likely used its pointy teeth to hunt and eat insects.
Both mammals and dinosaurs appeared near the end of the Triassic period, some 220 million years ago. When dinosaurs disappeared about 65 million years ago, mammals thrived. But ancient mammal fossils are still exceedingly rare, mostly because of their small sizes. As a result, paleontologists know of roughly one genus of mammal for every million years between 65 million and 220 million years ago—making for a woefully incomplete record.