GAINSVILLE, Fla., May 4 (UPI) -- Modern humans reached the Western Hemisphere during the last ice age and lived alongside giant mammals that since became extinct, a U.S. study found.
A study published in the Journal of Vertebrate Paleontology addresses the long-standing debate about whether human and mammal remains found in the early 1900s in Vero Beach, Fla., date to the same time period.
Measuring the concentration of naturally occurring metals absorbed during fossilization, researchers from the University of Florida have shown modern humans in North America co-existed about 13,000 years ago with large extinct mammals, including mammoths, mastodons and giant ground sloths.
"The Vero site is still the only site where there was an abundance of actual human bones, not just artifacts, associated with the animals," said researcher Barbara Purdy, University of Flordia anthropology professor and archaeology curator at the Florida Museum of Natural History on the university campus.
"Scientists who disputed the age of the human remains in the early 20th century just did not want to believe that people were in the Western Hemisphere that early.
"And 100 years later, every single book written about the prehistory of North America includes this site and the controversy that still exists," she said.
The researchers analyzed samples from 24 human bones and 48 animal fossils and determined the specimens were all from the late Pleistocene epoch about 13,000 years ago, the university reported.
"Humans would have been following the animals for a food supply but that's about all we know," Purdy said. "We know what some of their tools looked like and we know they were hunting the extinct animals but we know practically nothing about their family life, such as how these ancient people raised their children and grieved for their dead."