Post on 25-Feb-2022
Appreciating Human Diversity
Fifteenth Edition
Conrad Phillip Kottak
University of Michigan
A n t h r o p o l o g y
McGraw-Hill © 2013 McGraw-Hill Companies. All Rights Reserved.
7-3
THE PRIMATES
• Our Place Among Primates
• Homologies and Analogies
• Primate Tendencies
• Prosimians
• Monkeys
• Apes
• Behavioral Ecology and Fitness
• Primate Evolution
• Chronology
• Early Primates
• Miocene Hominoids
7-4
THE PRIMATES
• How and why are monkeys and apes similar
to humans?
• When, where, and how did the first primates,
monkeys, apes, and hominids evolve?
• How did diversity among Miocene proto-apes
figure in hominid origins?
7-5
PRIMATOLOGY
• Primatology: the study of nonhuman primates—fossils and living
apes, monkeys, and prosimians—including their behavior and social
life; helps anthropologists make inferences about early social
organization of hominids
• Two kinds of primates are especially relevant:
• Terrestrial monkeys and apes: primates that live on the ground
rather than in trees (ecological adaptation similar to humans)
• Great apes (chimps, gorillas, orangutans, bonobos), specifically
chimpanzees and gorillas
• Most closely related to us
• Humans and apes share a common ancestor; humans did
not descend from apes
7-8
OUR PLACE AMONG PRIMATES
• Similarities between humans and apes are evident in anatomy, brain
structure, genetics, and biochemistry; physical similarities between
humans and apes are recognized through zoological taxonomy
• Taxonomy: assignment of organisms to categories
• Classifications based on degree of genetic relatedness
• Phylogeny: genetic relatedness based on common ancestry
• Hominoidea (hominoids): a superfamily containing humans
and apes
• Classification of descending hierarchy, from most inclusive to
least inclusive
Species: group of organisms whose mating produces viable
and fertile offspring
7-9
OUR PLACE AMONG PRIMATES
• Homologies: similarities that organisms
share because of a common ancestry; similarities used to assign organisms
to the same taxon (category)
• Biochemical homologies between apes and humans confirm common
ancestry (i.e. humans, chimps, and gorillas have more than 98% of their
DNA in common)
• Humans: mammals (class) (share traits like mammary glands) that
belong to the order of primates (order)
• Primates share structural and biochemical homologies that distinguish
them from other mammals (i.e. versus carnivore, rodentia)
• Resemblances have been inherited from common early primate
ancestors
• Humans, whales, bats, eagles, lizards, frogs, and chimps – forelimb
bones
7-10
HOMOLOGIES AND ANALOGIES
• Extensive biochemical homologies between
apes and humans confer a common ancestry
• Analogies: similar traits that arise if species
experience similar selective forces and adapt to
them in similar ways; not result of common
ancestry
• Dolphin and fish
• Convergent evolution: process by which
analogies are produced
7-14
HOMOLOGIES AND ANALOGIES
• Hominid: the zoological family that includes
fossils and living humans, chimpanzees,
gorillas, and their common ancestors
• Hominin (tribe) describes all human species that
have ever existed, excluding chimps and gorillas
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PRIMATE TENDENCIES
• Primates have varied because of adapting to
diverse ecological niches
• Modern primates share homologies reflecting a
common arboreal (living in trees) heritage
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PRIMATE TENDENCIES
• Many trends in primate evolution best exemplified by
anthropoids: monkeys, apes, and humans
• Grasping:
• Five-digited feet
• opposable thumbs can touch all other fingers
• Flexible hands and feet
• Adaptation of hominins to bipedal locomotion: two-footed, upright locomotion
eliminated foot’s grasping ability
• Shift from smell to sight
• Stereoscopic vision
• Eye placement
• Brain organization
• Color vision
7-17
PRIMATE TENDENCIES
• Hand, rather than nose, is main touch organ
• Increased brain complexity
• Parental investment in single offspring
• Longer development period
• More attentive care
• More opportunities for learning
• Increased social complexity
• Sociality
• Social animals that live with others of their species
• Associated with parental investment
• Support of social group valuable
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PROSIMIANS
• Primate order has two suborders:
• Prosimians
• Anthropoids
• Early history of primates limited
to prosimian-like animals known
through the fossil record
• The first anthropoids appeared
around 50 million years ago
7-19
PROSIMIANS
• Some prosimians managed to survive
in Africa and Asia because
they adapted to nocturnal life
• They do not compete
with anthropoids, which
are active during the day
• Lemurs
• Tarsiers
• Lorises
7-20
MONKEYS
• All anthropoids share resemblances
that can be considered
trends in primate evolution
• Anthropoid suborder
has two infraorders:
• Platyrrhines: flat-nosed,
New World monkeys
• Catarrhines: sharp-nosed,
Old World monkeys, hominoids (apes and
humans)
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MONKEYS
• Different infraorder - New world monkeys (platyrrhines) were
reproductively isolated from the catarrhines before the latter split into
the Old World monkeys, apes, and humans
• All New World monkeys, and many
Old World ones, are arboreal
• Monkeys move differently
from apes and humans
• Their arms and legs are about same length &
move parallel to each other
• Most monkeys have tails
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NEW WORLD MONKEYS
• Live in the forests of Central and South America
• arboreal
• Have prehensile, or grasping, tails
• With one exception (night or owl monkey), all monkeys, apes,
and humans are diurnal
7-25
OLD WORLD MONKEYS
• Terrestrial and Arboreal
• Significant distinctions exist between arboreal and terrestrial Old World monkeys
• Size: arboreal monkeys smaller than terrestrial ones
• Sexual dimorphism: marked differences in male and female anatomy and
temperament and size
• Terrestrial males significantly larger and fiercer than terrestrial females,
but little or no such differentiation exists among arboreal monkeys
• Terrestrial monkeys - specializations in anatomy, psychology, and social
behavior enable them to cope with terrestrial life
• Social organization:
• Old World Monkeys
• Males seek mates outside natal group
• Core group of females
• Chimps and gorillas:
• Females more likely to leave natal group to seek mates
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APES
• Old World monkeys have separate superfamily (Cercopithecoidea)
• Humans and apes make up hominoid superfamily
• Subdivided into families:
• Great apes: orangutans, gorillas, chimpanzees
• Lesser (smaller) apes: gibbons, siamangs
• The third African ape: humans
• Hominid: the zoological family that includes fossils and living
humans, chimpanzees, gorillas, and their common ancestors
• Hominin (tribe) describes all human species that have ever existed,
excluding chimps and gorillas
• Traits shared by apes and humans
7-27
APES
• Live in forest and woodlands
• Light and agile gibbons are completely arboreal
• Skilled brachiation: hand-over-hand movement
through the trees
• Heavier gorillas, chimpanzees, and adult male
orangutans spend considerable time on the
ground
• Ape behavior and anatomy reveal past and
present adaptation to arboreal life
7-28
GIBBONS
• Smallest of the apes
• Spend most of their time just
below the forest canopy
• Use arms as balance when
they occasionally walk erect
• Tend to live in primary groups
composed of permanently
bonded males and females
and their preadolescent offspring
• Siamangs – slightly larger relative
7-30
ORANGUTANS
• Two existing species
• Marked sexual dimorphism
• Male is between chimps
and gorillas in size (large, approx.
200 lbs.)
• Move between arboreal
and terrestrial habitats
• Tend to be solitary
• Tightest social units: females
and preadolescent young
7-31
GORILLAS
• Three subspecies:
• Western lowland
• Eastern lowland
• Mountain (largest)
• Largest - Full-grown male may
be 400 pounds, 6 feet tall
• Marked sexual dimorphism
• Female weighs half as much as
male
• Primarily terrestrial
• Build nests in trees to sleep
• Live in a troop of males and
females with their offspring
• Silverback male – only male breeder
7-32
CHIMPANZEES
• Two kinds of chimpanzee:
• Common
• Pygmy (Bonobo)
• Adult males weigh 100 to 200 pounds
• Less sexual dimorphism than gorillas
• About the same as humans
• Social organization relatively well known – Jane Goodall
• Communities of about 50 chimps that
regularly split into smaller groups
• Exhibit dominance in relationships
• Chimps greet with gestures, facial expressions, and calls
• Social network of males closer; females more likely to migrate
outside natal group to find mate
• Occasional hunting parties
7-34
BONOBOS
• Live in humid forests of
Democratic Republic of Congo
• Adult males average 95 pounds
• Female-centered communities
• Peace loving
• Egalitarian
• Frequently use sex to
avoid conflict within community
7-35
BEHAVIORAL ECOLOGY AND FITNESS
• Behavioral ecology: study of evolutionary basis for social behavior
• Assumes genetic features of any species reflect a long history of differential
reproductive success (natural selection)
• Biological traits are transmitted across generations because they enabled
ancestors to survive and reproduce more effectively than competition
• Natural selection is based on differential reproductive success
• Members of same species may compete to maximize their reproductive fitness
• Individual fitness measured by number of direct descendants an individual has
• Inclusive fitness is measured by genes one shares with relatives
• Genetic contribution enhanced by cooperation, sharing, and other unselfish
behavior
• Individuals may invest in kin relations; sacrificing for kin increases genetic
contribution through shared genes