Lecture 6
Primate Behavior


Sociobiology
	Evolution affects behavior, both innate & learned
	Primates K-selected reproductively
		Few offspring
		Long period of dependency
		Social & learned behavior very important
Social behavior
	Dominance hierarchies & displays
		Multimale, multifemale groups
		Rank within sexes- Alpha Male
		Displays maintain rank
		Not always strongest, smarts & alliances work too
		Can be very violent- including to death
	Grooming and affiliative behavior
		Provides hygiene- gets rid of dirt, bugs
		Also cements social relationships
			"Stroke" higher ranks
			Maintain friendships
			Lower tensions after conflict
		Play- practice for adulthood
			Builds friendships
			Sets rankings
			Adults often join in as well
	Reproduction
		Usually high-ranking male when female in estrus
		Non-dominant males can mate on sly
			cultivate friendship w/female
			attack female when alone
		Pygmy Chimps (Bonobos) use sex like grooming
	Communication
		Wide variety of facial expressions & vocalizations
			Fear grin, play face, threat yawn
			pant hoot, fear scream
		Vervet threat calls
		Displays, grooming also communication
	Cultural behavior
		Learned behavior- Japanese macaque Imo & the sweet potatoes
		Hunting in chimpanzees
		Tool use in wild chimps
			All great apes make nests
			Termite and ant fishing wands
			Leaf sponges
			Nut-cracking stones
		Captive chimps
			Ape-language research
				Sign language
				Computer boards- Yerkes Primate Center in Atlanta
			Kanzi
				Learned language spontaneously
				Taught to make stone tools