The Living Primates Chapter 7

The Order of Primates 230 species grouped into two suborders of nonhuman primates Strepsirrhini – wet-nosed primates Includes all non-tarsier prosimians Lemurs, galagos and lorises Haplorhini – dry nosed primates Includes tarsiers and simians Tarsiers, monkeys and apes Living primates are not “better” than their predecessors Each possesses qualities that make it more adapted to a particular environment

Hands and Feet Grasping Primates have five digit feet and hands Tactile pads and nails Flexible hands and feet arboreal origins Humans and many other primates have opposable thumbs Thumb can touch other fingers May originate from insect eating Feet Most primates have grasping feet Shift to bipedal locomotion Walking on two feet eliminates useful foot grasping

Smell, Touch, and Sight Smell to Sight Nose to Hand Shift from reliance on smell to reliance on sight Stereoscopic vision – overlapping sight giving to depth perception Monkey, Apes and Humans Prosimians also generally lack color vision Night vision Nose to Hand In primates, the main “touch” organ is the hand

Stereoscopic (Binocular) Vision

Primate Brain and Skull Brain Complexity More brain tissue used for thought and memory than most other mammals High brain size to body size ratio Parental Investment Most primates give birth to single offspring Primates require and receive more attention as infants More opportunities for learning The skull of a male baboon compared with that of a red wolf Note the forward-facing eyes above the snout in the baboon, and the lateral position of the eyes of the wolf

General Primate Behavior Primates show a great deal of behavioral flexibility and the ability to learn from experience Longer period of dependency of offspring Great amount of parental investment Social groups and permanent association of adult males Mostly diurnal – primarily active during the day Most are arboreal - no nonhuman primate is fully terrestrial All spend some time in the trees Gathering Sleeping

Growth and Development The primates are characterized by the prolongation of gestation, during which the fetus grows rapidly Primates are also characterized by a long childhood period and a prolonged life span

The Living Primates The Primate order Divided into 2 suborders The Prosimii (prosimians) The Anthropoidea (anthropoids) The suborder Prosimii is divided into 2 infraorders The Lemuriformes (lemurs, lorises) The Tarsiiformes (tarsiers) The suborder Anthropoidea is divided into 2 infraorders The Platyrrhini (New World monkeys) The Catarrhini (Old World monkeys, apes, humans)

Prosimians The most primitive of the primates. Characteristics: Reliance on olfaction Laterally placed eyes Shorter gestation and maturation Dental specialization called the "dental comb” Rhinarium Moist, fleshy pad at the end of the nose Enhances ability to smell Survived competition in some regions due to nocturnal living Less competition with anthropoids Lemur isolation

The Lemuriformes Larger lemurs are diurnal and eat vegetable foods Smaller lemurs are nocturnal and insectivorous All prosimians possess second toes that end in grooming claws Lemuriformes live on the island of Madagascar (lemur, indri, aye-aye) and on the mainland of Africa and Asia (loris, potto, galago)

Lemur Dental Comb Formed by forward- projecting incisors and canines

The Tarsiiformes Characteristics: Range: Small stature Nocturnal, with large eyes Insectivorous Clinging and leaping Social pattern of a mated pair and their offspring Tarsiers possess grooming claws, but lack a dental comb Range: Tarsiers are found in Southeast Asia Islands of southeast Asia

Primate Distribution

Anthropoids Monkeys, Apes and Humans Common traits: Larger brain and body size Reduced reliance on the sense of smell Greater degree of color vision Bony plate at the back of the eye socket Different female reproductive anatomy Longer gestation and maturation periods

Monkeys 85% of all primate species New World monkeys Old World monkeys

Infraorder Platyrrhini New World Monkeys Monkeys of southern Mexico, Central American, and South America 70 species Almost exclusively arboreal Tend to be smaller than Old World Monkeys Many have prehensile tails Thumb is grasping, but not opposable The platyrrhine nose One nocturnal species Owl Monkey Two families Callitrichidae (marmosets, tamarins) and Cebidae (spider monkeys, capuchin monkeys, howler monkeys)

Common Marmoset - Callithrix jacchus Geoffery’s Spider Monkey - Ateles geoffroyi Venezuelan Red Howler - Alouatta seniculus

Infraorder Catarrhini Old World Monkeys, Apes, and Humans Characterized by: The catarrhine nose Two premolars per quadrant of the mouth A well-developed thumb that in most cases is opposable This infraorder is divided into two superfamilies Cercopithecoidea is composed of the Old World monkeys Hominoidea includes the apes and humans

Superfamily Cercopithecoidea The Old World Monkeys Habitats range from tropical forests to semiarid desert to snow-covered areas in Japan and China Mostly quadrupedal and arboreal Divided into subfamilies: Cercopithecines Baboons, macaques, and guenons Omnivorous Some are terrestrial Cheek pouches Ischial callosities Mostly in Africa Colobines African colobus monkeys and Asian langurs Herbivorous leaf eaters

Mandrill - Mandrillus sphinx Japanese Macaque - Macaca fuscata De Brazza's monkey - Cercopithecus neglectus

Superfamily Hominoidea Hominoids Characteristics distinguishing hominoids from monkeys: Larger body size Absence of a tail Shortened trunk More complex behavior More complex brain Increased period of infant development The family Hylobatidae (Lesser Apes) Gibbon and siamang The family Hominidae (Great Apes) Orangutan, gorilla, chimpanzee, bonobo and humans

Gibbons and Siamangs Found in the tropical areas of SE Asia Diet Fruits, leaves, flowers, and insects Society Monogamous pair and offspring Males and females delineate their territories with whoops and “songs”

Orangutans and Gorillas Belong to the subfamily Ponginae Borneo and Sumatra 40,000 Borneans (P. pygmaeus) 7,000 Sumatrans (P. abelii) Gorillas Belong to the subfamily Gorillinae One large silverback male, a few adult females, and their young offspring Confined to forested areas of western and eastern equatorial Africa Western Gorilla (G. gorilla) Western lowland (G. g. gorilla) Cross River (G. g. diehli) Eastern Gorilla (G. beringei) Mountain (G. b. beringei) Eastern lowland (G. b. graueri)

Subfamily Homininae Tribe Panini Tribe Hominini Chimpanzees (P. troglodytes) and bonobos (P. paniscus) Found in Equatorial Africa Chimpanzees Large communities of as many as 50 individuals Eat a variety of plant and animal foods Bonobos Male-female bonds constitute the societal core Only a few thousand, found South of the Congo (Zaire) River Sexuality Includes frequent copulations Uses: Greetings, forming social bonds, exchange, and conflict resolution Only non-human animal to engage in tongue kissing, face-to-face, and oral sex Tribe Hominini Humans

Chimpanzee - Pan troglodytes Bonobo – Pan paniscus