Live in Africa, Asia, South America

• Arboreal: live in trees

• Five digit hands with a thumb (“opposable thumb”)

• Nonspecialization: kept all 5 digits…did not specialize into fins, hooves, claws, or paws

• Limb flexibility: arm and hand rotation unique to primates

• Visual acuity (great sense of vision)

• frontal direction, stereoscopic (3-D), color perception (typical for animals that fly)

• Upright posture: bipedalism

Chapter 14-15-16 Blue Book (“Sitter”)

Lemurs: size of a cat, diurnal, found in Madagascar only, long furry tail, feed on leaves and fruits, live in structured groups

Lorises: solitary, slow moving, hunt insects, no tail, eyes close together

38-65 mill years. Smaller, nocturnal, arboreal, “furry”

38-50 mill years. Larger than prosimians, prominent skulls, more intelligent, full color 3-D vision, flat nose

Howler Monkey: arboreal, diurnal, rain forest habitat, feed mainly on leaves. Prehensile tails (“grasping” appendage). Loudest calls among primates (i.e. the name!!)…consequently, very low aggressive encounters.

Squirrel Monkey: smaller, arboreal, white face, dark eyes, long NON-prehensile tails used for balance, abundant food in leaves, fruits, flowers, and even insects…consequently – widespread habitat

Largest group of primates, African in origin.

Guenons: (Blue Monkey) Small (12-20lbs), arboreal, omnivores, live in troops of about 20 with one dominant male.

Larger sexual dimorphism due to competition among mating males,

Non-dominant males live solitary and will mate with wandering females of a troop.

Large vaiation in facial patterns

Baboons: largest monkey species (80-150lbs). adapted for walking on the ground (non-arboreal) using all 4 limbs.

Classic dimorphism…large difference btw male and female. Large muscles, long tail, large teeth and jaws…used only for aggressive “display”. Will actually stand and defend against predators!!

Complex social organization…both male (“alpha”) and female have rank.

Males leave the troops around age 4, females stay (prevents inbreeding)

Highly successful social species.

Hairless “Ischial callosites” on their butts…bare callous to sit

Apes: larger brain, no tail, Evolved from Old World Monkeys about 25 million years ago.

Gibbons: 3 feet tall. Strictly arboreal, mostly herbivorous.

Walk upright (bipedalism), but mostly move by Brachiation (“swinging). Can leap 20 feet and brachiate at 35 mph (fastest of all primates!!)

Thumbs are small and useless. Hands are used like hooks for swinging quickly

Monogamous couples live with offspring (like human!!). Leaves the family after 6-8 years.

Very little sexual dimorphism, due to low competition among males

Non confrontational, and due to their speed, are rarely preyed upon.

A. Orangutans

• first of the Great Apes to evolve (10 million years)

• Heaviest tree dwelling animal (arboreal) in the world (165lbs)

• Shy solitary animal, difficult to study naturally. Male and female socialize only to mate.

• Diet limited to hard to find fruits…better to be on you own!

• Can grasp with their feet

B. Gorillas

• only discovered in the 19th century by European scientists

• Contrary to myth, gorillas are the shyest and gentlest of all primates

…in spite of 300-600 lbs body standing over 6 feet tall!!

• Live in small family groups of about 8-24. One large dominant silver-back male leads the troop. Females move out after maturity (no inbreeding)

• Herbivorous – eats 70lbs of vegetation per day!!

• Cannot grasp with their feet….usually walk on all fours…NON-arboreal.

• Chest pounding may indicate threat, sexual arousal, play, frustration, or dominance.

• Yawning is a submissive gesture

• No “rump pad” (ischial callosites) – need to sleep in soft nest of leaves

• Threat display: (usually accompanied with loud screams and roars)

• 1. Bluff Charge: charge past adversary

• 2. Rush Charge: charge and stop short

• 3. Slam Charge: runs directly into adversary Dian Fossey: Gorilla in the Mist (1998)

c. Chimpanzee

• share over 98% of human genes…share common ancestor.

• Jane Goodall, Gombe, Tanzania (1960)…witnessed tool use and carnivores

• 60-90 lbs. Only 200,000 left in the wild.

• Usually NON-arboreal

• Unlike baboons, males stay with the group while females migrate.

• Huge array of facial expressions and vocalizations (pant-hoot)

• Males hunt monkeys in groups, each with a specific role (driver, blockers, chasers, ambushers)

• Chimps at war: they may seek out and kill members of a different community…not eaten for food. Only primate (other than human) to commit “murder”. Suggested that it’s for territorial expansion…war???

Discover chimpanzees; behavior videos, vocal calls

D. Bonobos

• used to be called pygmy chimps, but they’re not much smaller than chimps

• slimmer build, narrower shoulders, longer legs smaller head

• Inhabit different areas in the wild, so they don’t mix with chimps.

• enjoy water (unlike chimps)…also have small webbing between toes!

• walk upright more easily than chimps

• Society dominated by females (unlike chimps!)

• Like humans, bonobos are sexually active all the time

• Love, Not War: Sex is used to maintain harmony within the group!

•Sex is used to avoid aggression, reconcile, or relieve tension (even between same sex bonobos

Criteria traditionally used to show the evolution of human intelligence.

However, it no longer is used to determine intelligence because it is NOT linked with the development or complexity of the Central NS.

It’s an adaptive mechanism for animals to get food rather than changing their physical morphology.

We change our behaviors rather than our bodies(generalization rather than specialization)

Use of a stone to crack open a nut Use of a stick to access a termite mound

Reaching adulthood…

No other species has a longer developmental period than humans do, but other primates are close behind.

The investment in a long learning period and more intense parenting:

•Many animals learn by operant and classical conditioning. Primates spend much more effort on observational learning…watching another perform a behavior, then remembering what they see and trying it themselves in a safe setting.

•This process saves time and energy and also lowers the dangers associated with making a mistake in the wild.

•Taking advantage of what others in the group already know…building tradition (a collection of learned and socially transmitted behaviors)

•Evidence shows that the tendency to imitate is probably innate.

Observational learning occurs primarily in primates, but otherwise is actually quite rare in the animal kingdom (although does occur in a few others, such as some mammals and birds.

It is an efficient, fast, and safe way to function within your environment. The passing on of behaviors through generations may result in traditions.

For most animals, it is innate (you’re born with it). These instinctive responses protect animals from danger.

Lots of research still being done on this!! Nature versus nurture.

Important Early Childhood Experiences:

•Contact Comfort; touch, warmth, protective security

•Peer Relations; social isolation led to over-aggressiveness, sexual inadequacy, rejection by others…also, rocking, swaying, self-mutilation…never learned to get along with others in a very social society.

•Mother Deprivation; motherless mothers would sit on the infant, throw it against the wall, or try to kill it

* Harry Harlow’s work

Mother deprivation continued

• Infants who were raised by mothers then separated from them became passive, sad, upset, tearful, and depressed. (Anaclitic depression)

•Normal development was slowed down on all levels.

•How many of these findings can we generalize to humans?

•Play; may be social, exercise, or exploration.

•Costs; use energy, risk harm•Benefits must outweigh costs…healthy development of the brain and nervous system. (Greater stimulation led to larger brain with more synapses.) Practice movements needed for survival…deer vs. mountain lion playing. Explore in safety. Practice social behaviors. Stimulates the development of the nervous system and thinking abilities. And maybe just for fun!

So what do you think of all of this ‘behavior’ stuff?

Is this class over yet?