On Saturday afternoon, Denver Museum of Nature & Science
excavation crews uncovered one of the most spectacular discoveries yet at the Ice Age fossil dig site near Snowmass Village -- the skull and horns of a gigantic Ice Age bison.
As a Gould construction bulldozer carefully moved muddy silt near the bottom of the reservoir site, Dr. Ian Miller, the Museum's curator of paleontology and chair of the Earth Science Department, spotted an extremely large bison horn core exposed by the heavy machine operator. The horn was so large Miller initially mistook it for a mammoth or mastodon tusk.
The bulldozer made one more careful pass through the area and exposed a second horn core, which led scientists to the spot where a gigantic bison skull was discovered. When both horns were repositioned with the skull, the span of the horns was greater than six feet.
"I'm trying to think of a cooler fossil that I've ever seen in my life," said Dr. Kirk Johnson, the Museum's chief curator and vice president of Research and Collections. "This is the iconic fossil recovered thus far in the excavation."
The size of the skull and horns indicates the Ice Age animal was twice as large as modern bison. Scientific experts on the site hotly debated the age and identification of the specimen. Similar species found elsewhere in the western United States have indicated these extremely large bison are often found in sediments as old as 30,000 to 50,000 years old. If confirmed, this suggests that the Snowmass Village site contains fossils from a range of ages, not just a single age. If this is true, it would greatly increase the scientific significance of the site, according to Johnson.
The bison skull was put into a plaster of Paris jacket in the field, then the 250 pound specimen was carried to a truck to be transported to the Museum for preparation and preservation. The plaster jacket will be removed and the fossil will be carefully washed to remove the silt and mud. Scientists will collect samples from the skull and attempt to radiocarbon date it and extract ancient DNA.
Another Ice Age bison found earlier in the week at the dig site is possibly a juvenile of the same species as this new bison. All of the Ice Age scientific experts at the site agree that making a proper identification must wait until the skull can be cleaned and compared to other specimens in museum and university collections.