内容摘要：A group nomads rest as others work outside their homes on a bright sunny day in remote Kharnak village in the cold desert region of Ladakh, India, Saturday, Sept. 17, 2022. (AP Photo/Mukhtar Khan)

A group nomads rest as others work outside their homes on a bright sunny day in remote Kharnak village in the cold desert region of Ladakh, India, Saturday, Sept. 17, 2022. (AP Photo/Mukhtar Khan)

This illustration depicts giant sloths, humans and mastodons living alongside one another in central Brazil 27,000 years ago, during the Pleistocene period. (AP/Peter Hamlin)This illustration depicts giant sloths, humans and mastodons living alongside one another in central Brazil 27,000 years ago, during the Pleistocene period. (AP/Peter Hamlin)

Researcher Mírian Pacheco shows fossil sloth bones called osteoderms dated around 27,000-years-old in a lab at the University of Sao Paulo on September 2, 2024. Scientists think these were intentionally altered and used as jewelry by ancient humans. (AP/Christina Larson)In a lab at the University of Sao Paulo, researcher Mírian Pacheco holds in her palm a round, penny-sized sloth fossil. She notes that its surface is surprisingly smooth, the edges appear to have been deliberately polished, and there’s a tiny hole near one edge.“We believe it was intentionally altered and used by ancient people as jewelry or adornment,” she said. Three similar “pendant” fossils are visibly different from unworked osteoderms on a table — those are rough-surfaced and without any holes.

These artifacts from Santa Elina are roughly 27,000 years old — more than 10,000 years before scientists once thought that humans arrived in the Americas.Originally researchers wondered if the craftsmen were working on already old fossils. But Pacheco’s research strongly suggests that ancient people were carving “fresh bones” shortly after the animals died.

This photo provided by researchers shows prehistoric drawings at the Santa Elina excavation site in the Mato Grosso state of Brazil. (Águeda Vilhena Vialou, Denis Vialou via AP)

This photo provided by researchers shows prehistoric drawings at the Santa Elina excavation site in the Mato Grosso state of Brazil. (Águeda Vilhena Vialou, Denis Vialou via AP)While the exact timing of humans’ arrival in the Americas remains contested — and may never be known — it seems clear that if the first people arrived earlier than once thought, they didn’t immediately decimate the giant beasts they encountered.

And the White Sands footprints preserve a few moments of their early interactions.As Odess interprets them, one set of tracks shows “a giant ground sloth going along on four feet” when it encounters the footprints of a small human who’s recently dashed by. The huge animal “stops and rears up on hind legs, shuffles around, then heads off in a different direction.”

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group. The AP is solely responsible for all content.VIENNA (AP) — As construction crews churned up dirt to renovate a Vienna soccer field last October, they happened upon an unprecedented find: A heap of intertwined skeletal remains in a mass grave dating to the 1st-century Roman Empire, likely the bodies of warriors in a battle involving Germanic tribes.