By Mindy Weisberger
There’s a little extra thumb-thing on the hand of the aye-aye, a strange-looking nocturnal lemur native to Madagascar. Tucked near each wrist is a small nub of bone and cartilage that’s like a miniature thumb — and until recently, scientists didn’t know this pseudothumb existed.
Aye-ayes (Daubentonia madagascariensis) are considered by many to be the weirdest of all primates, with their coarse and frazzled bedhead fur, oversize ears, bulging eyes and bony, spindly fingers, one of which is exceptionally long.
But the discovery of the hidden mini-thumb makes aye-ayes even weirder: They are the only primate to have evolved an extra finger to help with grasping. The formerly unknown digit even has its own fingerprint, scientists reported in a new study.
Continue reading by clicking the name of the source below.