Bio 281 2011 Lecture 18 - Animal Culture

Animal culture Consequences of sociality Animals are exposed to behavior, sometimes novel, of others Do animals display culture? What is culture? “The totality of the mental and physical reactions and activities that characterize the behavior of individuals composing a social group collectively and individually in relations to their natural environment, to other groups, to members of the group itself and of each individual to himself” - Franz Boas (1911) “An extrasomatic (nongenetic, nonbodily), temporal continuum of things and events dependent upon symboling. Culture consists of tools, implements, utensils, clothing, ornaments, customs, institutions, beliefs, rituals, games, works of art, language, etc.” - Leslie White (~1949) What is culture? “Patterns, explicit and implicit, of and for behavior acquired and transmitted by symbols, constituting the distinctive achievement of human groups” - Kroeber and Kluckhohn (1952) Cultural transmission May occur via copying… “Learned systems of meaning, communicated by means of natural language and other symbol systems, having representational, directive, and affective functions, and capable of creating cultural entities and particular senses of reality” - Roy D'Andrade (~1984) …or via direct instruction Tool use in chimpanzees “The universal human capacity to classify, codify and communicate their experiences symbolically…a defining feature of the genus Homo” - Wikipedia (2006) Culturally transmitted behavior must persist beyond life of originator 1 Cultural transmission in macaques Cultural transmission in macaques First learners = her mother, two juveniles • Macaques on Koshima Island provisioned by humans • One-year old female named Imo introduces novel behavior Passed mother to offspring (imitation and teaching) In 1956, Imo originated another feeding behavior Cultural transmission in macaques Mature males never learned either behavior Cultural transmission in macaques 1950s: Japanese diverted river flow to cool hot springs for human use 1979: one event in 14 months of observation Colonized by macaques along similar demographic lines stone-play 1983: habitual behavior in approximately half of the troop Adult males did eventually learn to use thermal pools A culture of conformity? A culture of conformity? Within 10 days of first exposure to apparatus Two months later black bars = “poke”, white bars = “lift” 2 A culture of conformity? Percent of tasks demonstrated of that type Percent of demonstrations observed Chimps trained at either “lift” or “slide” technique Feeding strategies in cetaceans Feeding strategies in cetaceans Rudimentary attempts by calves Percent lobtail feeders Humpback whales release cloud of bubbles prior to breaching Calf Dive sometimes preceded by tail slap (lobtail feeding) Feeding strategies in cetaceans In spite others’ ability to spontaneously generate (control group) Faithfully transmitted to 5-6 others (lift left, slide right) 2 3 4 5 6 7 8 9 Increased lobtail feeding due to diet change from herring to sand lance? sand lance Feeding strategies in cetaceans “Sponging” in Shark Bay, Australia Occurs within one matriline Analysis (1 male, 12 females, 172 non-spongers) suggests no genetic basis Same population observed “conching” in 2007 and 2009 3 Feeding strategies in cetaceans Cultural transmission in birds • Recent evidence of another novel feeding strategy in captive orcas • Pattern of cultural transmission similar young male half brother adult female adult female calf adult male Cultural transmission in birds Cultural transmission in birds Null hypothesis: behavior spread not via cultural transmission, but via independent learning events Titmice were the culprits Chickadees show high rates of spontaneous opening Does cultural transmission make a culture? Many species have complex societies, but no culture • Criteria for culture include – Differences among populations – Cultural transmission (i.e. social learning) – Differences not genetic or purely ecological Evidence suggests three independent origins followed by cultural transmission Culture in great apes: chimpanzees • Combined 151 years of data (7 sites) • 39 cultural traditions customary in ≥ 1 population, absent in others • Include tool use, courtship rituals, and grooming techniques • Excludes ecological differences – e.g. nesting in relation to predation risk 4 Culture in great apes: orangutans colored square > colored circle > monochrome circle > empty circle Is culture evolutionarily important? • Similar analysis yielded 24 cultural characters • Included snagriding, leaves as gloves and sound amplifiers Conclusions regarding animal culture • Animals undoubtedly transmit behaviors culturally in a manner similar to humans • Some animals possess cultures similar to our own, though substantially less complex • Cultural transmission of behavior may be evolutionarily important So what is culture? • Many whales species have low diversity of mitochondrial DNA • Most pronounced in those with matrilineal social system – suggestive of cultural effect? “An animal tradition that rests either on tuition of one animal by another or on imitation by one animal of acts performed by another” - Galef (1992) 5