Sloths weren’t always slow-moving, furry tree-dwellers. Their prehistoric ancestors were huge, reaching up to 4 tons, and when startled, they brandished immense claws. Scientists once believed that the first humans to arrive in the Americas soon killed off these giant ground sloths, as well as many other massive animals, through hunting.
However, new research suggests that people may have arrived in the Americas earlier than once thought. These findings hint at a remarkably different life for early Americans, one in which they shared prehistoric savannas and wetlands with enormous beasts.
Archaeological sites have yielded tantalizing clues, including fossils of giant ground sloths with signs of being manipulated by humans. The bones show evidence of being processed while still fresh, rather than thousands of years after the animals’ deaths.
One significant discovery was made at the Santa Elina site in central Brazil, where bones of giant ground sloths were found to have been altered by humans. The fossils, dated to around 27,000 years ago, were initially thought to be old, weathered remains. However, researcher Mírian Pacheco’s analysis revealed that the surface was surprisingly smooth, with edges that appeared to have been deliberately polished, and a tiny hole near one edge. Pacheco believes that the fossil was intentionally altered and used as jewelry or adornment by ancient people.
Other recent discoveries, including the excavation of the 14,500-year-old stone tools and preserved animal hides at Monte Verde, Chile, have also challenged the long-held idea that humans arrived in the Americas during a single, rapid wave of migration.
The findings suggest that humans may have been existing alongside the massive beasts, including giant ground sloths, mastodons, and saber-toothed cats, for at least 10,000 years, without causing their extinction.
The new discoveries have reinvigorated debates about the timing of human arrival in the Americas and the impact of their presence on the environment. While the exact timing may never be known for certain, it seems clear that the first people to arrive in the Americas did not immediately decimate the giant beasts they encountered.