Here’s a very cute demonstration of the basic differences between monkeys and apes! No apes have tails while most monkeys do. Apes also tend to swing from branch to branch while monkeys tend to jump and run along them.
Mee Na is a 6 month old white handed gibbon and Vincent (featured previously https://www.wfft.org/primates/childs-living-toy-rescued/) is an 8 month old dusky langur. As orphans, they are both being raised by our hospital staff until they are old enough to be paired with others of their kind.