Scientists refer to lemurs (includes sifakas), lorises, galagos, pottos, and tarsiers as " prosimians" to distinguish them from monkeys, apes and humans. "Prosimian" means "pre-ape", that is, primates that appear in the fossil record before monkeys, apes and humans. They more closely resemble primitive primates that lived millions or tens of millions of years ago than do other living primates. Generally, prosimians look and act much differently than monkeys and apes. For example, lemurs tend to have longer fox-like, wet noses, compared to monkeys which have flatter faces and dry noses. One could guess from this difference that smell plays a greater role in prosimian behavior than it does in that of monkeys, who tend to be more visually oriented. ( Duke Univ. 2003)
Prosimians are the most primitive extant primates; they represent forms that were ancestral to monkeys, apes and humans. Prosimians are the only primates native to Madagascar, and are also found in Southeast Asia. With the exception of the tarsiers, all of the prosimians are in the suborder Strepsirrhini.
