NY Times 1978
Objections We don't think about our reproductive success. Neither do red deer 2. Our behaviour isn't genetically determined Neither is the red deer’s 3. The approach leads to nastiness (racism, sexism, …) Facts are facts; what we do with them is a separate issue
3 main approaches to human b.e. • Treat humans just like any other species • Human behavioural ecology / Darwinian anthropology • 2. Study our evolved psychology (how we perceive, choose, …) • Evolutionary psychology • 3. Build cultural evolution into behavioural ecology • Gene-culture coevolution / Dual inheritance theory
Human behavioural ecology / Darwinian anthropology behavioural solutions to ecological problems human behaviour still adaptive (thanks partly to its plasticity) so, one can apply main methods of behavioural ecology 1. test suitability of behaviour for particular function(s) 2. test whether that increases survival & reproductive success 3. test whether behaviour matches environment across different environments (comparative method)
A behavioural ecology study of recipes Sherman, P.W., Billing, J. 1999. Darwinian Gastronomy: Why We Use Spices. BioScience 49: 453-463.
2. Evolutionary psychology a) behaviours fit past, not present, environments less use of correlations w/ r.s., comparative method b) but we still have the brain that evolved then study psychology as tools for past selective problems
A male mate choice module Low WHR correlates with: higher oestrogen lower rate of health disorders So, do males prefer low WHR? Increasing WHR -> Western undergraduates “Universal” Matsigenka (Peru) Increasing weight -> Yu, D.W., Shepard, G.H. 1998. Is beauty in the eye of the beholder? Nature 396: 321-322.
3. Gene-culture coevolution a) cultural transmission Now he acts the Grenadier, Calling for a Pot of Beer. Where’s his Money? He’s forgot: Get him gone, a Drunken Sot. 1725 1916 Rat a tat tat, who is that? Only grandma’s pussy cat. What do you want? A pint of milk. Where’s your money? In my pocket Where’s your pocket? I forgot it. O you silly pussy-cat. • Variation • Heritable • Variation in reproduction • More suitable traits do better • Traditions that do better have adaptations 1950 Mickey Mouse In a public house Drinking pints of beer. Where’s your money? In my pocket. Where’s your pocket? I forgot it. Please walk out. Opie, I., Opie, P. 2000. The Lore and Language of Schoolchildren. NYRB Classics (reprint of 1959 original).
3. Gene-culture coevolution • b) adaptive value of culture • c) interplay of genes and culture Holden, C., Mace, R. 1997. Phylogenetic analysis of the evolution of lactose digestion in adults. Human Biology 69: 605-628.
Where’s behavioural ecology headed? [I’ll say something brilliant here; just haven’t quite decided what]