Ancient Footprints Tell a Tale of Early Hunters

A series of ancient fossils reveal our ancestors once tracked and hunted giant ground sloths, a new study published in Science Advances reports. The footprints — which were analyzed by researchers from various U.S. universities — were found 10 years ago at the White Sands National Monument in New Mexico. Though the human prints first caught the researchers’ eyes, they soon found the marks were inside the tracks of giant ground sloths.

That suggests the humans were closely following or stalking the much larger creatures. “The White Sands trackway — a series of tracks and footprints — shows that someone followed a sloth, purposely stepping in their tracks as they did so,” said lead author David Bustos, a naturalist at White Sands National Monument, according to USA Today.

Long extinct, giant sloths were once one of the most fearsome animals on Earth. Not only were they massive — standing seven or eight feet tall on their hind legs — but they were also equipped with gigantic claws. Even as herbivores, the mammals could readily protect themselves when needed.

To overcome that, ancient humans likely secretly hunted them through ambushes or sneak attacks. That falls in line with the tracks, which reveal evidence of evasion and defensive behavior near the human footprints.

The fossils are different than other such prints because they give direct evidence of interaction between humans and giant ice age megafauna. Further analysis of the tracks could help researchers get a better idea of, not just how humans used to hunt, but also if they played a role in the extinction of such large prey.

“Our data confirms that human hunters were attacking megafauna and were practiced at it,” wrote the researchers in the study, according to UPI. “Unfortunately, it doesn’t cast light on the impact of that hunting. Whether humans were the ultimate or immediate cause of the extinction is still not clear.”