Fossil

Fossil

Evidence of mastodons of all ages — including infants and juveniles — are turning up at the Ice Age fossil dig site near Snowmass Village, according to the Denver Museum of Nature & Science.

The finds so far include a small skull of an infant (the size of a basketball), a small skull of a juvenile (the size of a beer keg), a tiny femur or thigh bone that may have belonged to a fetus (it measures seven inches in length), and more than two dozen tusks.

“Based on our previous research, we know that we are finding male and female mastodons of all ages,” said Dr. Kirk Johnson, the leader of the museum's excavation team and vice president of the Research and Collections Division, in a press release issued Friday. “Since beginning the dig last fall, we have uncovered 26 total mastodon tusks, which means we have evidence for at least 13 to 20 different mastodons on this site. We'll know more as we study the growth rings on each tusk and identify pairs of tusks that belonged to individual mastodons.”

Prior to the discoveries near Snowmass, at a reservoir excavation project, there had only been three other mastodon finds on record in Colorado, and none yielded mastodon skulls.

“We have so many speculative questions, like why were so many mastodons in this one location, and what can scientists learn from this discovery?” Johnson added. “At this point, we only have speculative answers.”

Scientists are busy collecting data and mapping the finds — details that can help them piece together what occurred at the site, an ancient lake where hundreds of Ice Age fossils have been recovered. Scientists believe the oldest fossils being recovered are 130,000 to 150,000 years old.

The crew is on the 21st day of a seven-week dig — the museum's largest-ever fossil excavation project. Thirty-six scientific experts, 107 trained volunteers, 35 staff members, and nine interns are working at the site. Beginning Saturday, the crew size will increase by 10 to 12 people.