Last Friday I gave you this exploded skull from the incredible Galerie d’anatomie comparée et de Paléontologie in Paris:

As I suspected, it was a bit of an easy one for many of you, but that provided the chance for some cryptic clue fun.

So my thanks to Agata Stachowiak, Chris, Allen Hazen, henstridgesj, Claire Miles and witcharachne who all hinted at an identification of Sloth, more specifically a Two-toed Sloth, I think of the species Choloepus hoffmanni Peters, 1858 as opposed to C. didactylus Linnaeus, 1758, which appears to have a smaller angular process on the mandible and a less broad zygomatic region.

A two-toed sloth (Choloepus hoffmanni) at La Selva Biological Station, Sarapiqui, Costa Rica. By Geoff Gallice

The teeth of Sloths are fascinating, due to their fairly simple rooting and their impressively sharp premolars that look like canines.

These Sloths have an interesting feature of their hair, which has a groove to help support algae, which help keep the Sloth camouflaged. This is pretty handy given the Sloth’s notorious lack of speed with which to escape predators. This may help explain the need for those sharp premolars as well!