#Sloth ice age full

#Sloth ice age full

McDonald estimates that the approximately 110 bones recovered from the adult Megalonyx represent about 60 percent of the full skeleton, making it the second most complete of its kind. We plan to get back out there as soon as the water in the river goes down, hopefully this month or the next. “Discovering these bones was a thrill for everyone. “We were concerned that the fossil deposit was running out after the disappointing results from the dig in December, but it’s clear that we have encountered the bone bed again,” Semken adds. Semken says the group’s excavation efforts were halted in 20 because of flooding, and the excavation last December turned up empty-handed. The recent bone discoveries are the first in nearly three years for the project, which began in 2001. “Someone a lot smarter than me is going to have to figure out how these bones have managed to survive virtually unblemished while the more robust limb bones appear to be missing.” “We have a nearly complete rib cage now for the juvenile sloth,” Semken says, adding that the baby sloth scapulas are among the animals’ most fragile bones. Semken and David Brenzel, another primary investigator for the project, identified the findings on site as a scapula (shoulder blade) from the baby sloth-only the second recovery from this specimen-and two rib bones from the older toddler sloth. The new sloth identification comes on the heels another major excavation discovery at the original site: On April 25, three more major Megalonyx bones were discovered. “Of all of the Megalonyx sites discovered, the Tarkio specimens will provide the basis for the most comprehensive analysis of sloth paleobiology and ecology of any to date,” McDonald adds. He says his goal was to establish an accurate catalog of the bones as a basis for further investigations. McDonald, whose recent visit to the University of Iowa was made possible by a National Science Foundation grant, checked all the bone identifications as part of his analysis.

But Paramylodon sloths were equipped with broader, triangular claws for digging rather than the sharp claws of the Megalonyx, which were used for grabbing at woody vegetation like tree branches, McDonald says. “Greg saw that bone, and you could see his face light up,” says Holmes Semken, project leader and emeritus professor in the University of Iowa’s Department of Geoscience.īoth Paramylodon and Megalonyx were nearly elephant-sized Ice Age mammals that became extinct about 12,000 years ago. McDonald identified the bone, which was discovered two years ago, as the animal’s fifth metacarpal-once connecting its wrist to its little finger-during a visit to the museum. Greg McDonald, the senior curator of natural history for the National Park Service’s Park Museum Management Program, is a consultant on the Tarkio Valley Sloth Project, which is sponsored by the University of Iowa’s Museum of Natural History. The five-inch long bone, from a Paramylodon harlani, was originally misidentified as a Megalonyx jeffersonii sloth, three of which-an adult, a toddler, and a baby-have been uncovered at the site. IOWA (US)-Researchers excavating a site in southwestern Iowa have discovered a bone from a type of giant Ice Age sloth never before recorded in the state. This bone from an Ice Age sloth is the first of its kind found in Iowa.