Title: An Overview of The Primates
1Chapter 6
- An Overview of The Primates
2Chapter Outline
- Characteristics of Primates
- Primate Adaptations
- Primates Classification
- A Survey of the Living Primates
- Endangered Primates
3Primates As Mammals
- There are approximately 190 species of nonhuman
primates - Primates belong to
- Vertebrate class - Mammalia
- Subgroup of placental mammals.
4Characteristics of Primates
- Fur (body hair)
- Long gestation followed by live birth
- Homeothermy, the ability to maintain a constant
body temperature - Increased brain size
- Capacity for learning and behavioral flexibility.
5Binocular Vision in Primates
6Primate Limbs
- A tendency towards erect posture.
- Hands and feet possess grasping ability.
- Features of the hands and feet
- 5 digits on hand and feet
- Opposable thumb
- partially opposable great toe
- Tactile pads enriched with sensory nerve fibers
at the ends of digits
7Dental Formulae
8Primate Senses and the Brain
- Color vision is a characteristic of all diurnal
primates, nocturnal primates lack color vision. - Depth perception is made possible by eyes
positioned forward on the front of the face. - Decreased reliance on the sense of smell
(olfaction). - The brain has expanded in size and become
increasingly complex.
9Primate Maturation
- Longer periods of gestation
- Reduced numbers of offspring
- Delayed maturation
- Extension of the entire life span.
10Primate Learning and Behavior
- Have a greater dependence on flexible, learned
behavior. - Tend to live in social groups.
- Males are permanent members of many primate
social groups, a situation unusual among mammals.
11Arboreal Hypothesis
- Arboreal (tree) living was the most important
factor in the evolution of primates. - Prehensile hand is adapted to climbing in the
trees. - A variety of foods led to the omnivorous diet and
generalized dentition.
12Visual Predation Hypothesis
- Primates may have first adapted to shrubby forest
undergrowth and the lowest tiers of the forest
canopy. - Forward facing eyes enabled primates to judge
distance when grabbing for insects. - Flowering plants may have influenced primate
evolution.
13Primate Habitats
- Most live in tropical or semitropical areas of
the new and old worlds. - Most are arboreal, living in forest or woodland
habitats. - No nonhuman primate is adapted to a fully
terrestrial environment all spend some time in
the trees.
14Primate Diet and Teeth
- Generally omnivorous, reflected in their
generalized dentition. - Most eat a combination of fruits, leaves, and
insects. - Some primates kill and eat small mammals.
- Some primates are dietary specialists on leaves.
- Most have four types of teeth incisors, canines,
premolars and molars.
15Primate Locomotion
- Most primates are quadrupedal, using all four
limbs in their locomotion. - Arm swinging is found among the apes.
- Siamangs of southeast Asia use this exclusively.
- Monkeys that use a combination of leaping and arm
swinging are termed semibrachiators. - Prehensile tails, found only among the new world
monkeys, are used as an aid to locomotion.
16Human and Chimpanzee Chromosomes
- Human chromosome2 has banding patterns that
correspond to chimpanzee chromosomes 12 and 13. - This suggests that human chromosome 2 resulted
from the fusion of ape chromosomesduring the
course ofhominid evolution.
17Revised PartialClassification of the Primates.
18Alternative Classifications of Great Apes and
Humans
19Prosimians
- The most primitive of the primates.
- Characteristics
- Reliance on olfaction
- Laterally placed eyes
- Shorter gestation and maturation periods
- Dental specialization called the "dental comb
20Lemurs
- Found on the island of Madagascar and other
islands off the coast of Africa. - Extinct elsewhere in the world.
- Characteristics
- Larger lemurs are diurnal and eat vegetable
foods fruit, leaves, buds, and bark. - Smaller lemurs are nocturnal and insectivorous
(insect -feeding).
21GeographicalDistribution of Modern Lemurs
22Lorises
- Found in tropical forests and woodlands of India,
Sri Lanka, southeast Asia, and Africa. - Characteristics
- Use a climbing form of quadrupedalism.
- Some are insectivorous others supplement their
diet with fruit, leaves, gums, and slugs. - Females frequently form associations for foraging
or in sharing the same sleeping nest.
23Tarsiers
- Small nocturnal primates found on the islands of
southeast Asia. - Characteristics
- Eat insects and small vertebrates which they
catch by leaping from branches. - Basic social pattern appears to be a family unit
consisting of a mated pair and their offspring.
24Anthropoids(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
- Fused mandible
25Monkeys
- Represent about 70 of all primate species.
- Divided into two groups separated by geography
and several million years of evolutionary
history - New world monkeys
- Old world monkeys
26New World Monkeys
- Almost exclusively arboreal.
- Found in southern Mexico and central and south
America. - Two families Callitrichidae and Cebid
27New World Monkeys Callitrichidae
- Give birth to twins
- Live in families composed of a mated pair or a
female and two adult males, plus the offspring. - Males are involved with infant care.
28New World Monkeys Cebid
- Possess prehensile tails.
- Most live in groups of both sexes and all ages.
- Others live as monogamous pairs with subadult
offspring.
29Old World Monkeys
- Habitats range from tropical forests to semiarid
desert to snow-covered areas in Japan and china. - Characteristics
- Most quadrupedal and arboreal
- All belong to the Cercopithecidae family
- Divided into subfamilies, the cercopithecines and
the colobines.
30Geographical Distribution of Modern Old World
Monkeys.
31Hominoids (Apes and Humans)
- Characteristics distinguishing hominoids from
monkeys - Larger body size
- Absence of a tail
- Shortened trunk
- More complex behavior
- More complex brain and enhanced cognitive
abilities - Increased period of infant development and
dependency
32Gibbons and Siamangs
- Found in the tropical areas of southeast Asia.
- Adaptations for brachiation may be related to
feeding while hanging from branches. - Diet is largely fruit with leaves, flowers, and
insects. - Basic social unit is a monogamous pair and their
offspring. - Males and females delineate their territories
with whoops and songs.
33Orangutans (Pogo pygmaeus)
- Found in heavily forested areas of Borneo and
Sumatra. - Almost completely arboreal.
- Large
- males 200 pounds
- females 100 pounds
- Pronounced sexual dimorphism.
- Solitary
- Principally frugivorous (feed-eating).
34Geographical Distributionof Modern African Apes
35Gorillas (Gorilla Gorilla)
- Largest of the living primates.
- Confined to forested regions of central Africa.
- Males can weigh up to 400 pounds, females 200
pounds. - Primarily terrestrial, using a posture called
knuckle walking. - Groups consist of one large silverback male, a
few adult females, and their subadult offspring.
36Chimpanzees (Pan Troglodytes)
- Found in equatorial Africa.
- Anatomically similar to gorillas particularly in
limb proportions and upper-body shape. - Locomotion includes knuckle-walking on the ground
and brachiation in the trees. - Eat a variety of plant and animal foods.
- Large communities of as many as 50 individuals.
37Bonobos (Pan paniscus)
- Only found in an area south of the Zaire river.
- Population is believed to only number a few
thousand individuals. - Exploit the same foods as chimps, including
occasional small mammals. - Male-female bonds constitute the societal core.
- Sexuality includes frequent copulations
throughout the female's estrous cycle.
38Humans (Homo Sapiens)
- The only living species in the family Hominidae.
- Human teeth are typical primate teeth.
- Dependence on vision for orientation to the world
39Humans (Homo Sapiens)
- Flexible limbs and grasping hands
- Omnivorous diet
- Cognitive abilities are the result of dramatic
increases in brain size. - Bipedal
40Endangered Primates
- Over half of all living primates are endangered,
many face immediate extinction - Most primates live in tropical rain forests that
are being destroyed for their natural resources. - Some primates are hunted for their meat.
- Others are victims of the exotic pet trade.
41Tropical Rain Forests of the World (Before Recent
Massive Destruction)
42Hunting of Primates
- In West Africa the most serious problem is
hunting to feed the growing human population. - Estimated that thousands of primates, are killed
and sold for meat every year. - Primates are also killed for commercial products.
43Conservation Efforts
- Many developing countries have designated areas
as national parks or reserves. - Private organizations, such as the rain forest
information center in Ecuador, have set up
biological reserves. - Through conservation and educational programs,
primate species may have a chance at escaping
extinction.