27,000-year-old pendants crafted from the skin of extinct giant sloths could help rewrite the human history of the Americas

• Researchers found what appeared to be pendants made from the now-extinct giant sloth.
• The artifacts are believed to date from around 25,000 to 27,000 years ago.

Pendants made of bony material from giant sloths suggest humans lived in South America thousands of years earlier than previously thought, researchers say.

Scientists believe the artifacts date to around 25,000 to 27,000 years ago, according to a new study published in the journal Proceedings of the Royal Society B, the Royal Society's main biological research journal.

While it was long thought that humans migrated to the Americas by crossing a land bridge from Siberia into Alaska around 13,000 years ago, recent research has challenged that view.

"We now have good evidence — together with other sites from South and North America — that we have to rethink our ideas about the migration of humans to the Americas," Mirian Liza Alves Forancelli Pacheco, study co-author and archaeologist at the Federal University of Sao Carlos in Brazil, told The Associated Press.

The remains of the now-extinct giant sloth were discovered at the Santa Elina rock shelter in Brazil, and they included thousands of osteoderms — hard bony deposits that form within the skin of certain animals.

According to the study, three of the osteoderms appeared to have been polished and had holes drilled into them, suggesting humans had modified them into what was likely "personal ornaments," researchers said. They added that the holes were not caused by natural abrasion, The AP reported.

The scientists said that the pendants were made within days or a few years of the animal dying, the report adds.

Findings across such sites also challenge the idea that humans arrived in the Americas in one wave of migration over the Bering land bridge, according to Briana Pobiner, a co-author and paleoanthropologist at the Smithsonian Institution's National Museum of Natural History in Washington.

"It's very likely that multiple waves of people came to Americas," she said, according to The AP.

Giant ground sloths could reach 13 feet long, weighed more than a thousand pounds and were equivalent in size to an Indian elephant. It walked on all fours and was one of the largest creatures in South America, per the report.