Sloths mate and give birth while hanging in the trees. Three-toed sloth babies are often seen clinging to their mothers—they travel by hanging on to them for the first nine months of their lives.

Sloths mate and give birth while hanging in the trees. Young two-toed sloths are often seen clinging to their mothers; they travel by hanging onto them for the first five weeks of their lives.

In the above clip narrated by Sir David Attenborough, a male sloth swims as fast as he can—which is pretty fast, all things considered—to track down a female sloth’s mating call. It’s no secret that ...