Unit 4 Primates Chapter 15 Apes Great and Small

Swingers: Gibbons Rainforest Arboreal Eat fruits, leaves, eggs Coat and facial colors Vocal patterns Move by brachiation Small Long fingers and small thumb Do not sleep in nests monogamous

Orangutans Solitary, shy (only together mating) Rainforest Sumatra, Borneo Adult males 165 lbs, 8 ft arm span Females half size (sex dimorphism) 50 year life span Eat fruit, forage a lot Males territorial, charging, some fighting Females parent alone

Gorillas Shy and gentle Live in small family groups Silverback is alpha male over harem Rainforest, plants and fruit, forage Ground dwelling, hands and feet not specialized for trees Knuckle walking

Silverback leads troop single file Silver at about 11 yrs and older Groups 8-24 Silverback and blackbacks lookout for trouble

Threat gestures Tight lips Eye contact Growls, pants Teeth baring Stiff strut Chest beats Charges (bluff, slam, fight-rare)

Submission gestures Cower No eye contact Bite lip Yawn Groom others Fake eating

Gorillas cont. Nap during day Elaborate night nests on ground or higher up Females do not mate w/ relatives Females solicit male attention, bond to alpha male

Gorillas cont. Young learns social structure Caring mothers Ride on belly or back for many years

Chimpanzees Share 99% of DNA w/ humans Chimps, gorillas, humans are distinctly diff Humans did NOT come from chimps! We share a distant common ancestor before there were such things as chimps, gorillas, or humans. 3-4 mya

Chimpanzees Western and central Africa Forest, woodlands, savanna Eat fruits, leaves, insects, meat Males 90 lbs, females 70 lbs Arms longer than legs 45 year life span Nest at night

Walk on knuckles Live mostly on ground Use tools Variety of facial expression, body gestures, calls Genitals swell during estrus Females present themselves

Young are cared for many years Rank associated w/ mother Males dominant and aggressive Loose hierarchy Form coalitions, manipulate for power Hierarchy changes over time Complex relationships

Dominance gestures Charging Hair erect Use props for sight and noise Grunting Screams

Submission gestures Bobbing Crouching Pant grunting Fear grin Grooming

Groups vs.. community Groups AKA party 3-6 Related Live w/in community Community Larger territory

Females migrate out, males stay Females must join group where other females accept her Group hunting: driver, blockers, chasers Group defense of territory

Chimps go to war Border patrol parties Raiding parties Group holds male down while others beat him Safety in numbers Need to be a part of group Use weapons

Bonobos Similar in size to chimps Diff build and facial structure Live more south Walk upright easier No fear of water (web-like toes)

Live in large communities Female dominated Use of sex for bonding Same sex bonding as well Used to avoid or solve conflict Maintain harmony (not dominance)

Can apes use language? Can learn sign language Learn to use computers Use objects to communicate with humans

Conclusions to studies: 1. Can learn symbol systems to comm 2. Can string together symbols 3. Abilities exceed other non-human primates 4. Short sentences 5. Symbols are objects or actions