Types of Primates

Prosimians and Anthropoids The primate order has two suborders: Prosimians: (from the Latin for “before monkeys”) because they possess traits common to the ancient primates. Anthropoids: Monkeys, apes, and humans are grouped together as anthropoids (from the Greek for “humanlike”).

Prosimians and Anthropoids The early history of the primates is limited to Prosimian-like animals known through the fossil records. The first anthropoids, ancestral to monkeys, apes, and humans, appeared about 50 million years ago.

Prosimians and Anthropoids Some prosimians managed to survive in Africa and Asia because they were adapted to nocturnal life. As such they were not competing with anthropoids, which are active during the day.

Prosimians and Anthropoids Lemurs in Madagascar had no anthropoid competition until people arrived on that island about 2,000 years ago. In their behavior and biology, Madagascar’s Lemurs, which include some50 species, show adoptions to an array of environments, or ecological niches.

Prosimians and Anthropoids Their diets and times activity differ. Lemurs eat fruits, other plant foods, eggs, and insects. Some are nocturnal; others are active during the day. Some are totally arboreal; others spend some time in the trees and some on the ground.

Prosimians and Anthropoids Another kind of Prosimians is the tarsier, today confined to Indonesia, Malaysia, and the Philippines. From the fossil record, we know that after 55 million years ago, several genera of tarsierlike prosimians lived in Asia, North America, and Europe, which were much warmer then than they are now. The one genus of tarsier that survived is totally nocturnal.

Prosimians and Anthropoids Lorises are other nocturnal prosimians found in Africa and Asia.

Common Traits of Prosimians Arboreal or tree living Grasping hands and feet Long, mobile limbs Quadrapedal Binocular vision Upright sitting position Nails instead of claws Use scent marking to communicate – wet nose

Monkeys All anthropoids share resemblance that can be considered trends in primate evolution in the sense that these traits are fully developed neither in the fossils of primates that lived prior to 50 million years ago nor among contemporary prosimians.

Monkeys The anthropoid suborder has two infraorders: Platyrrhines (New World Primates). Catarrhines (Old World monkeys, apes, and humans). Old World monkeys, apes, and humans are all catarrh. Being placed in the same taxon (infraorder, in this case) means that Old World monkeys, apes, and humans are more closely related to each other than to New World monkeys. In other world, one kind of monkeys (Old World) is more like a human than it is like another kind of monkey (New World).

Monkeys The New World monkeys were reproductively isolated from the catarrhines before the latter diverged into the Old World monkeys, apes, and humans. This is why New World monkeys are assigned to a different infraorder.

Monkeys All New World monkeys, and many Old World monkeys are arboreal. Whether in the trees or on the ground, monkeys move differently than apes and humans. Their arms and legs move parallel to one another, as dogs’ legs do. Unlike apes, which have longer arms than legs, and humans, who have longer legs than arms, monkeys have arms and legs of about the same length.

Monkeys Most monkeys have tails, which help them maintain balance in the trees. Apes and humans lack tails. The apes’ tendency toward orthograde posture is most evident when they sit down. When they move about, chimps, gorillas, and orangutans habitually use all four limbs.

New World Monkeys New World monkeys live in the forests of Central and South America. Unlike Old World monkeys, many new world monkeys have prehensile, or grasping, tails. Sometimes the prehensile tails has tactile skin, which permits it to work like a hand.

Old World Monkeys The Old World monkeys have both terrestrial and arboreal species. Baboons and many macaques are terrestrial monkeys.

Old World Monkeys Certain traits differentiate terrestrial and arboreal primates. Arboreal primates tend to be smaller. Smaller animals can reach a greater variety of foods in shrubs and trees, where the most abundant foods are located at the ends of branches. Arboreal monkeys typically are lithe and agile. They escape from the few predators in their environment. Large size, by contrast, is advantageous for terrestrial primates in dealing with their predators, which are more numerous on the ground.

Old World Monkeys Another contrast between arboreal and terrestrial primates is in sexual dimorphism- marked differences in male and female anatomy and temperament. Sexual dimorphism tends to be more marked in terrestrial than in arboreal species. Baboon and macaque males are larger and fiercer than are females of the same species. However, it’s hard to tell the sex of an arboreal monkey.

Old World Monkeys Of the terrestrial monkeys, the baboons of Africa and the (mainly Asiatic) macaques have been the subjects of many studies. Terrestrial monkeys have specializations in anatomy, psychology, and social behavior that enable them to cope with terrestrial life.

Old World Monkeys Adult male baboons, for example, are fierce looking animals that can weight 100 pounds. They display their long, projecting canines to intimidate predators and when confronting other baboons. Facing with a predator, a male baboon can puff up his ample mane of shoulder hair, so that the would-be aggressor perceives the baboon as larger than he actually is.

Old World Monkeys Old World monkeys, however, have developed their own characteristic anatomical specializations. They have rough patches of skin on the buttocks, adapted to sitting on hard, rocky ground and rough branches.

Apes The Old World monkeys have their own separate superfamily (Cercopithecoidea), while humans and the apes together compose the hominoid superfamily (Hominoidea). Among the hominoids, the so-called great apes are orangutans, gorillas, and chimpanzees. Humans could be including here too. The lesser (smaller) apes are the gibbons and siamangs of Southeast Asian and Indonesia.

Apes Several traits are shared by apes (and humans) as distinct from monkeys and other primates. Body size tend to be larger. The life span is longer. There is a longer interval between births of infants, which depend longer on their parents. There is a tendency toward upright posture, although habitual upright posture, although habitual upright bipedalism is characteristic only of hominine. The brain is larger, the muzzle or face is shorter and less projecting, and no hominoid has a tail.

Apes Apes live in forests and woodlands, and almost all apes are threatened or endangered today because of human encroachment. The light and agile gibbons, which are skilled brachiators, are completely arboreal. Brachiators is hand-over-hand movement through the trees.) The heavier gorillas, chimpanzees, and adult male orangutan spend considerable time on the ground.

Gibbons Gibbons are found in the forests of Southeast Asia, especially in Malaysia. Smaller than apes, male and female gibbons have about the same average height (3 feet). Gibbons spend most of their time just below the forest canopy (treetop). For efficient brachiation, gibbons have long arms and fingers, with short thumps.

Gibbons Slender built, gibbons are the most agile apes. They use their long arms for balance when they occasionally walk erect on the ground or along a branch. Diet mainly of fruits, with occasional insects and small animals. Gibbons and siamange, their slightly larger relatives, tend to live in primary groups, which are composed of a permanently bonded male and female and their preadolescent offspring.

Orangutans There are two existing species of orangutan, Asiatic apes that belong to the genus Pongo. Highly endangered, contemporary orangs are confined to two Indonesian islands. Orangutans once were found throughout Southeast Asia, but today 90% of them live in Indonesia. The degree of sexual dimorphism in Orangutans is striking.

Orangutans Adult males weight more than twice as much as females. Orangutans are arboreal, although they climb, rather than swing from trees. Orangutans have a varied diet of fruit, bark, leaves and insets. 80% of the Orangutans habitat has been either depopulated or totally destroyed.

Gorillas With just one species, there are three subspecies of gorillas. The smallest subspecies of gorilla, lives mainly in forests in the Central African Republic, Congo, Cameroon, Gabon, Nigerian and Guinea. There are only 650 mountain gorillas left. These are the larges gorillas, with the longest hair (to keep them warm in their mountainous habitat.)

Gorillas Full-grown male gorillas may weight 400 pounds, and stand 6 feet tall. The average female weights half as much. Gorillas spend little time in the trees. When gorillas sleep in trees, they build nests, which usually are no more than 10 feet off the ground. By contrast, the nests of chimps and female orangutan may be 100 feet above ground. Most of the gorilla’s day is spent feeding.

Gorilla Like most primates, gorillas live in social groups. The troop is a common unit of primate social organization, consisting of multiple males and females and their offspring. Although troops with up to 30 gorillas have been observed, most gorillas live in groups of 10 to 20. Gorilla troops tend to have fairly stable memberships, with little shifting between troops. Each troop has a silverback male. The silverback is usually the only breeding male in the troop

Gorillas Members of a mountain gorilla troop sit with primatologist Dian Fossey. Photo Credit: Peter Veit/DRK

Chimpanzees Chimpanzees have two species: Pan troglodytes (the common chimpanzee) and Pan paniscus. Like humans, chimps are closely related to the gorilla, although there are some obvious differences. Chimps live in tropical Africa, but they range over a larger area and more varied environments than gorillas.

Chimpanzees Chimps prefer fruits, but they are omnivorous, adding animal protein to their diet by capturing small mammals, birds’ eggs, and insects. Chimps weight between 100 and 200 pounds. There is much less sexual dimorphism among chimps. Females approximate 88% of the average male height.

Chimpanzees The long-term research of Jane Goodall provides provide especially useful information about Chimpanzees. Goodall has described communities of about 50 chimps, all of which know one another and interact from time to time.

Chimpanzees Communities regularly split up into smaller groups. When chimps, which are very vocal, meet, they greet one another with gestures, facial expressions, and calls. Males occasionally cooperate in hunting parties.