Ring-tailed lemurs have four thin fingers and a thumb, with an opposable first toe on the lower appendage to help with climbing trees.
Ring-tailed Lemurs have four thin fingers and a thumb on their upper and lower appendages, each ending in a dark colored nail.
The thumbs on the upper appendages are not opposable as the joint is fixed. The first toe on the lower appendage is opposable and is used while climbing trees in the mid- and upper-level canopies.
Sources: (Baumhofer, 2017; Cawthon Lang, 2005; Gould, Sussman, & Sauther, 2003; Sussman, 1991; Wilson & Hanlon, 2010)
Image: Mathias Appel
