Cebidae
Aotidae
Pitheciidae
Atelidae
Cercopithecidae
Hylobatidae
Hominidae
The simians (infraorder Simiiformes) are the "higher primates" very common to most people: the monkeys and the apes, including humans. Simians tend to be larger than the "lower primates" or prosimians.
Classification and evolution
The simians are split into three groups. The first division is literally as wide as the Atlantic Ocean. The New World monkeys in clade Platyrrhini split from the simian line about 40 million years ago, leaving clade Catarrhini occupying the Old World. This group split about 25 mya between the Old World monkeys and the apes. Earlier classifications split the primates into two large groups: the "Prosimii" (strepsirrhines and tarsiers) and the "Anthropoidea" (simians).