Chapter 6: Primate Evolution

• Introduction to the Primates• Why do anthropologists study primates?

– To understand human evolution by:• Homology

– The same adaptations in close relatives offer clues to design structures in ancestral and contemporary human populations (culture?)

• Analogy– How do other primates respond to the same

and different environmental pressures?

ANTH 101, Fall 2005, Exam 1

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Adaptive Radiation

• What was the niche?

• Birds and Mammals move into vacated Dino niches

• Early primates were common

• In Tropics implies that they were forest/tree dwellers

• Climate was warm and wet (rainforests)

Distribution

Derived Traits

• Opposable Thumbs• Nails (no claws)• Hind limb dominated locomotion• Reduced sense of smell• Increase importance of sight (stereoscopic

vision)• Small litters• Large Brain• Unspecialized teeth

Two types (suborder):

• Prosimians: VCL, Lemurs (Madagascar), Aya-ayes, Lorises, & Galagos.

• Anthropoides: Old and New World Monkey and Apes (humans)

New World Monkeys

• Marmosets and tamarins (small bodied)– Twins– Polyandry– Monogamous families with alloparental care

• Others: – Howlers– Spider– Wooly– Squirrel– Capuchins (tool users)– Night monkeys (owl monkey)– others

Old World Monkeys

• Colobus & Lagurs (harems)

• Macaques, baboons & vervets (multi-male and multi-female, matrilocal)

• Apes– Derived traits

• Lack tails• Bigger brains• Y-Shaped pattern on lower molar

Lesser apes: Gibbons and Siamangs (Asia, true brachiators, Monogamous)

Great Apes:– Gorilla (knuckle walking, Africa,

polygamous harems)

Orangutans (Asia, solitary, home range, rape )

Common Chimps (Africa, promiscuous, multi-male and

multi-female)

Bonobos “Pygmy Chimps” (Africa, very promiscuous, multi-male and multi-female,

matriarchal)

Chimps and Humans are our closest relatives (98.4% Genes)