Oregon paleontologists found a fossilized skull and a set of teeth from a new species of prehistoric beaver that may have lived in the eastern Oregon area at least 28 million years ago.
New Species Microtheriomys Brevirhinus
The fossils were discovered about a mile from the John Day Fossil Beds National Monument visitor center. This particular prehistoric beaver specimen is thought to be a relative of today’s beaver, which happens to be the state animal of Oregon. The new species has been named Microtheriomys brevirhinus.
Beaver Fossils Will Help Establish Evolutionary Framework
The paleontologists involved in the study of the prehistoric beaver fossil say that analyzing it will help them to determine an evolutionary framework for the beaver species. Its age was determined by dating the layers of volcanic ash located in the area through radioactive isotope testing.
All of the fossils of the prehistoric beaver were discovered in the northern hemisphere, and the information on them was printed in the May 2015 copy of Annals of Carnegie Museum.
The excavation site includes a stretch of wasteland that undergoes changes in the clay ground. The clay tends to shrink or swell depending on the temperature, causing the fossils and bones to be pushed up and out into the air where they can be found. This is how the prehistoric beaver fossil was found.
Differences between modern and prehistoric beaver
The prehistoric beaver appears to be half the size of today’s beavers. The paleontologists say it is related to a species of beaver that came to North America via the Bering land bridge around seven million years ago. It would have lived among other prehistoric creatures such as three-toed horses, two-horned rhinos, sabretooth tigers, and other early mammals.
This prehistoric beaver species will help enhance our understanding of the beaver’s evolution, according to the scientists from the University of Oregon behind the study. The area of the John Day Fossil Beds National Monument is rich in previous fossil finds, as hundreds of other fossils from around 100 different mammals have been discovered there in the past.
