The ordinal name primates, means the first or primary animals. This naming convention reflects the egocentric orientation of humans, but is of no help in defining the group of mammals included in it. Primates are mainly arboral mammals, but terrestrial forms occur in several groups. Most primates are omnivorous. Several groups are almost entirely herbivorous. The galagos and tasrsiers are largely insectivorous. Most primates are pentadactyl, although some fingers are shorter in some Lorises. The thumb is reduced in several brachiating forms and completely absent in spider monkeys. In most primates the digits are prehensile and the pollex and/or the hallux are more or less opposable. These prehensile and apposable digits yield a hand or foot with great dexterity, allowing the animal to better grasp and manipulate objects. In general the sense of smell in primates becomes less acute as the hand becomes better adapted for manipulation. Primates have developed very good vision, particularly those that are diurnal. The field of vision of the two eyes overlap considerably, resulting in more precise depth perception. The retina of some nocturnal primates is composed entirely of rods. The eyes are directed more or less frontally, and the face is foreshortened in many forms. Only humans are completely bipedal.

A single species, Homo sapiens, is nearly worldwide in distribution. Otherwise other members of the order are found in the Americas from eastern and southern Mexico to southeastern Brazil, most of Africa, Madagascar, the southwestern part of the Arabian Peninsula, south-central and southeastern Asia, Japan and the East Indies as far as Sulawesi and Timor.

Walker includes 13 Families, 71 genera and 233 species within the Order Primates. Since humans are themselves primates, the order has attracted much interest and investigation, and there are numerous views on classification, especially between the order and family levels. Simpson's (1945) scheme is followed by Walker.

Superfamily Cheirogaleoidea
Family Cheirogaleidae

Superfamily Lemuroidea
Family Lemuridae

Family Lorisidae

Family Galagidae

Family Tarsiidae

Family Cebidae
Subfamily Callitrichinae

Subfamily Cebinae

Subfamily Saimiriinae

Family Aotidae

Family Pitheciidae
Subfamily Callicebinae

Family Atelidae
Subfamily Alouattinae

Subfamily Atelinae

Superfamily Cercopithecoidea
Family Cercopithecidae
Subfamily Cercopithecinae

Subfamily Colobinae

Superfamily Hominoidea
Family Hylobatidae

Family Hominidae


List of Specimens | Explore Collections | Brain Sections | Brain Evolution | Brain Development | Brain Circuitry | Brain Functions | Location and Use | Related Web Sites | Contact Us | Search MSU Database | Personnel | Home