What is your favorite type of sloth - two-fingered or three-fingered?
There are currently two families of sloths and six species. While it is customary to designate the two families as "two-toed" and "three-toed," in fact all sloths have three toes on each foot. The distinction is in their fingers - so it is good that the student who asked this question did not make that mistake.
People typically are most familiar with three-fingered sloths, and they love the sort of black mask they have on their faces. Two-fingered sloths are less flashy in appearance. They typically have brown fur that is lighter in color on their faces. They have a bunch of moss growing on their fur that they graze on from time to time. The fur also provides a habitat for moths. Recently scientists have discovered that the moths provide nutrients for the moss, which then is more nutritious when the sloths eat it. In exchange, the moths get a nice, warm home and some protection from predators. Sloths are fascinating animals.
I personally met with some two-fingered sloths at the Zoological Wildlife Center in Rainier, OR. For the most part, they were pretty friendly, although I did spend quite some time getting a particular old grump to warm up to me. My family had a better experience feeding and petting some more personable sloths.
I usually say that I prefer the two-fingered sloths. Mostly, I like them because they look cool, they are less popular, they are friendlier (I think), and Mr. Sloth (my puppet) is a two-toed sloth.
Recently, though, I have developed a soft spot for a particular species of three-fingered sloth: the pygmy sloth. This is the most endangered of all the sloths. These sloths are endemic only on one island near Panama. They have coloring similar to that of other three-toed sloths, but are much smaller. An adult pygmy sloth is 19 - 21 inches long. I like these sloths because they are small, cute, and people need to know about them so we can try to save them.