IT’S BEEN A VERY LONG DAY AND I THOUGHT FOR A SECOND I’D BEEN DRINKING TOO MUCH: But no, Science Magazine is doing its job. North American human-giant ground sloth interactions in the terminal Pleistocene. Remarkable footprints found in White Sand National Monument.

BEHAVIOR:

…we present the first well-documented co-association of unshod human tracks with those of extinct Pleistocene ground sloth in the Americas, and we infer behavioral implications from these contemporaneous tracks.

MORE:

We argue that the tracks evidence temporal and spatial associations of sloths and humans and infer that humans actively stalked and/or harassed sloths, if not hunted them. The absence of a carcass is not surprising for several reasons. The vast majority of hunts by modern hunter-gatherers are unsuccessful (for example, 94% for Hadza) (22). Sloths are so densely muscled that an outright kill is unlikely. Even if the hunt had been successful and the animal had died in the study area, the wetting and drying cycles and high pH rapidly degrade bones; thus, preservation of bones in the terminal Pleistocene therefore remains improbable. In terms of alternative explanations, it is possible that the human trackmaker was simply stepping in the sloth footsteps to follow a preexisting path in soft terrain. We dismiss this interpretation because the step length results in a long and uncomfortable human stride. The estimated stature of the human trackmaker (1.4 m; Tracks TE-A-44, -45, and -46; table S2) yields a stride of 0.6 m, contrasted with the sloth stride of 0.8 to 1.1 m. It is possible that the behavior was playful, but human interactions with sloths are probably better interpreted in the context of stalking and/or hunting. Sloths would have been formidable prey. Their strong arms and sharp claws gave them a lethal reach and clear advantage in close-quarter encounters.

American hunters stalking very slow but dangerous game. Cool.