The Living Primates

• Understanding the concepts of primatology

• Common Primate Traits• Classification of Primates• Various Primates• Explanations of Variable Primate

Adaptations• Distinctive Human Traits

Primatology

• The goal of this study is to understand how different primates have adapted automatically and behaviorally to their environments.

• The results of such studies may help us to understand the behavior and evolution of the human primate.

Common Traits• All Primates belong to the class Mammalia,

and they share all the common features of mammals.

• Humans are the exempted mammals, since mammals are covered with dense hair or fur.

• Mammals are warm-blooded. The body temperature is more or less constantly warm and usually higher than that of the air around them.

Common Traits• Almost all mammals give birth to live young

that develop to a considerable size within the mother and are nourished by suckling from their mother’s mammary glands.

• The young have relatively long period of dependence on adults after birth.

Physical Features

• Many skeletal features of the primates reflect on arboreal existence.– Areas and important parts of the bones are great

supporters of the body.– the limbs are flexible, built to withstand both

pushing and pulling forces.– The clavicle also gives primates great freedom of

movement, allowing their shoulders to move up and down, back and forth.

Physical Features

• Omnivores– Primates eat all kinds of food, including insects, small

animals, fruits, vegetables, grass and roots.• The teeth of the primates: molars and

premolars for chewing.• The front teeth: incisors and canines are

specialized in lower primates.• All primates have prehensile and opposale

thumbs.

Physical Features• Most primates’ vision are characterized as

stereoscopic or depth vision.• Large brain relative to body size.• Primates reproductive system;– Males have pendulous penis– Females of most primates have two nipples in the

chest.– Uterus is constructed to hold single fetus only

Physical Features/common traits

• Forward-facing eyes• Grasping hands and feet• Rotating forearm (referring to the ulna and

radius)• Relatively larger brain; reduction in sense of

smell (olfactory bulbs); and expansion of primary visual area.

Social Features

• According to anthropologists; Primates, as described as diurnal, developed many patterns of social behavior.– Dependency and Development in a Social Context– Primates at Play– Learning from others

Dependency and Development in A Social Context

• Social relationships begin with the mother and other adults during the fairly long dependency period of primates.

• The prolonged dependency of infant monkeys and apes probably offers an evolutionary advantage.

Primates At Play

• Anthropologist like Harlow, provided an explanation about social learning in young primates.

• Play is important for learning.• It provides practice for the physical skills

necessary or useful in adulthood.

Learning from Others

• Among humans, children imitate others, and adults often deliberately teach the young.

Classification of Primates

Prosimians

• They depend much on smell for information than do anthropoids.

• They typically have more mobile ears, whiskers, long snouts and relatively fixed facial expressions.

Lemur-like forms

• They are quadrupeds.• Their mode of locomotion is vertical clinging and

leaping.• They are usually vegetarians, fruit eaters, leaves,

barks and flowers.• Most of them are nocturnal.• they are mostly living with 60 members.• Most of the females are dominant than males

particularly over access of food.

Loris-like Forms

• They are all nocturnal and aboreal.• They are mostly found in both Southeast Asia

and sub-Saharan Africa.• Subdivided as Loris and bushbabies(galagos).• Their locomotion is more likely on hopping on

the ground.• Female adults and children stay together thus,

male disperse.

Tarsiers

• They are nocturnal, tree-living tarsiers, and can only be found in the islands of Philippines and Indonesia.

• They are usually insect eaters and sometimes capture and eat other small animals like lizards.

• They get their name from the elongated tarsal bones.

• Male and female sing together at night in order to advertise their territories.

Tarsiers

• Anthropologists classified tarsiers into two:– Strepsirhines (includes lemurs and loris)– Haplorhines(includes tarsiers and anthropoids)

Anthropoids• The sub-order of the group anthropoids

includes the humans, apes, and monkeys.• They shared common several traits in varying

degree:– Rounded braincase– Reduced, nonmobile ears– Relatively small, flat faces instead of

muzzles(covering).• They have highly efficient reproductive system.

Anthropoids• Anthropoids order is divided into two:– PLATHYRRHINES– CATARRHINES

• PLATHYRRHINES– Have broad, flat-bridged noses with nostrils facing

outward– These monkeys are usually found in the New World, (in

Central and South America.)• CATARRHINES– Have narrow noses with nostrils facing downward.– These includes the monkeys of the old World(Africa,

Asia, and Europe), as well as apes and humans.

Plathyrrines

Catarrhines

Anthropoids• OLD WORLD MONKEYS– Also known as cercopithecoids– Related more closely to humans than to the New

World monkeys.• NEW WORLD MONKEYS– They possess three premolars than the old world– They are considered as prehensile(grasping tail)– Two main families are the marmosets and

tamarins and the cebid monkeys.

The Hominoids: APES and HUMANS• Divided into three groups:– Hylobates(the lesser apes/gibbons and siamangs)– Pongids(the great apes/orangutans, gorillas,

chimpanzees)– Hominids ( the humans)

Hylobates

Pongids

Hominids

Distinctive Human TraitsPHYSICAL TRAITS• Only humans consistently walk erect on two

feet.• Comparing with the other anthropoids, pongids

walk on two feet but only for short periods.• All other primates require thick, heavy

musculature to hold their heads erect• Humans missed this thick musculature; our

heads are balanced on top of our spinal columns.

Distinctive Human Traits• The human brain is more larger than of the

apes.• Humans may engage to sex every time of the

year.• Apes and other pongids only engage

periodically.

Distinctive Human TraitsBEHAVIORAL TRAITS• Tool making and inventiveness• Language

Distinctive Human TraitsOTHER HUMAN TRAITS• Humans are one of the primates who are

terrestrial.• Humans have the longest dependency period

of any of the primates, requiring extensive parental care up to 20 years.

• Humans have system of in having division of labor by gender in food-getting and food-sharing in adulthood.

• Humans have more gender-role specialization.