Fossilized Saber-Toothed Squirrel Bears Resemblance to Scrat From Ice Age

Posted on November 2, 2011

Cronopio Dentiacutus Ancient Mammal Like Scrat

The fossilized skull and teeth of an ancient shrew-like mammal were found in Argentina. The saber-toothed squirrel is the second oldest mammal skull found in South America. Cronopio dentiacutus was shrew-sized, about 4-6 inches in length. Cronopio was a dryolestoid, an extinct group distantly related to marsupials and placentals of today. Cronopio had long canine teeth, but it was an insectivore with a diet of the insects, grubs and other bugs of the time. It lived when giant dinosaurs roamed the earth - more than 100 million years ago. It made its home in a vegetated river plain.

Paleontologist Guillermo Rougier, Ph.D., professor of anatomical sciences and neurobiology at the University of Louisville, says the animal does bear resemblance to a famous cartoon character. Rougier says, "It looks somewhat like Scrat, the saber-toothed squirrel from Ice Age."

Scrat from Ice Age

Rougier also said, ""We knew it was important, based on the age of the rocks and because we found skulls. "Usually we find teeth or bone fragments of this age. Most of what we know of early mammals has been determined through teeth because enamel is the hardest substance in our bodies and survives well the passage of time; it is usually what we have left to study. The skull, however, provides us with features of the biology of the animal, making it possible for us to determine this is the first of its kind dating to the early Late Cretaceous period in South America. This time period in South America was somewhat of a blank slate to us. Now we have a mammal as a starting point for further study of the lineage of all mammals, humans included."

The research paper was published here in the journal Nature. You can read more about the small toothy mammal on BBC News and National Geographic.

Illustration by Jorge Gonzalez (top)/20th Century Fox (bottom)