Zoology: Bones

The three-toed sloth (Bradypus tridactylus) lives in the dense jungle regions of Central and South America. They can weigh between 6-11 lbs (3-5kg) and reach up to 19 in (½ m) in length. Solitary and almost entirely arboreal, three-toed sloths have an unusually low metabolic rate and thermoregulate by sunning themselves. While one may think two and three-toed sloths are related, they actually are not! Their separate evolution began 35 million years ago in the late Oligocene. They are separated into two different families because of physical and behavioral differences. Aside from having a different number of fingers, two-toed sloths have 6-7 cervical vertebrae while three-toed have 8-9 cervical vertebrae, two-toed have a vestigial tail while three-toed have short tails about 2-3 inches long. The skull of the three-toed sloth is short and rounded, with an incomplete zygomatic arch, a jugal with ventral and dorsal processes, and peg-like teeth. Compare this with our two-toed sloth skull, BC-098. Both would be an excellent addition to a zoology or evolutionary biology course. 2-part skull (separate cranium & jaw).
3 ½" L x 2" W x 2 ¼" H / 8.4 cm x 4.7 cm x 5.5 cm

Oval display base is available on demand.