Description
This order includes the lemurs, tarsiers, monkeys, and apes. Most live in tropical or subtropical regions of the Americas, Africa, and Asia.
Fossil evidence indicates that Plesiadapis may have been their ancient ancestor. It looked somewhat like a squirrel, and it lived in North America and Europe around 55 million years ago. Scientists have long recognized that the animals in this group are still evolving. This is reflected in the classification system that divides the order / clade into two groups: (1) the primitive Prosimians, which have physical characteristics found in the earliest known species, including the lemurs, lorisiforms, aye-aye, and tarsiers; and (2) the more
advanced simians, which include the monkeys and apes.