Prosimians

primates The taxonomic order of mammals that includes prosimians (lemurs and tarsiers), monkeys, apes, and humans; characteristics include large brain, stereoscopic vision, and grasping hand.

In some prosimians, such as the Red-bellied Lemur, scent glands occur atop the head. In many species, olfaction is highly tuned to pheromones; a male silkworm moth, for example, can sense a single molecule of bombykol.

A member of the order of mammals that includes anthropoids and prosimians.
primitive
[L. primus, first]
Not specialized; at an early stage of evolution or development.

See also: Mouth, Nucleotide, Organ, Membrane, Protein