"As our eyes got accustomed to the environment, we started to notice large animal bones resting at the bottom and on the walls of the pit," Nava said.
Overall, international researchers led by anthropologist James Chatters identified the remains of more than 26 large mammals. They included a gomphothere, an extinct elephant-like creature, which was dated to around 40,000 years ago, saber-toothed cats and giant ground sloths, which were largely extinct in North America by 13,000 years ago. Extant species included puma, bobcat, coyote, Baird's tapir, collared peccary and a bear.
In this picture, Nava inspects a forelimb of an extinct Shasta ground sloth, a species not previously found so far in the Americas.