Friday, February 5, 2010

Three Toed Sloths

There are only four different species of three toed sloths: the Brown-throated, Pale-throated, Maned, and Pygmy. They are all arboreal (live in trees), and have a reputation for being quite slow. They are, however, great swimmers. The sloth pictured here is wet because he just went for a swim.

Interestingly enough, they don't have normal teeth (kind of a molars--kind of not) called molariforms. Also interestingly, they do not maintain a constant body temperature--it fluctuates with the outside air temperature. As a result they need to live in warm, humid environments near the equator [like Panama and northern South America].

The picture is credited to Bryson Voirin and the BBC.  The link to great slide show is here.


  1. So this beggars the question: Are they mammals? If I remember correctly, all mammals are warm-blooded.

  2. Great question Lord Haldane. Once upon a time I learned that the bare-boned definition of mammals was a "lactating hirsute." I'm not so sure that still doesn't apply. What does that mean? It means that all mammals have, at the minimum, mammary glands and are hairy. Live birth, for instance, isn't a requirement. Neither, in this case is endothermy. I think though, that the inability to regulate body temperature is a little exaggerated. Fluctuations in internal body temperatures must be accounted an allowed for...marine life would have to be flexible. The heat capacity of water would force a varying internal temperature. IMHO

  3. Oh, and Carly, I like Sloths too. And I love the picture of the sloth I posted. Thanks, for the post.

  4. The baby ones are especially adorable. :)