Among the megafauna bones scattered on the floor of Hoyo Negro alongside Naia’s skeleton were the remains of giant ground sloths — animals that are hard to visualize accurately because there is nothing living that captures their scale and their specific quality.

Ground sloths were not small.

The largest species — Eremotherium and related genera — could reach lengths of six meters and weights exceeding three thousand kilograms.

They were massive, slow-moving herbivores, distantly related to the modern tree sloths of South America and Central America but not resembling them in any way that would be obvious.

They walked on their hind legs and the outer edges of their front limbs, leaving distinctive tracks.

They used their powerful forelimbs — armed with large, curved claws — to pull down branches and strip vegetation.