Defending a territory Home range is area an animal inhabits Territory is the area of home range that is defended. Female may choose male based on his position in the lek. Think of it as guys hanging around at the corner. Courtship rituals take a lot of energy Selection favors polygamous mating systems Pair bods ensure mating and rearing of offspring Polygynous animals have male impregnation of more than one female, with male not taking care of kids Polyandrous females mate with more than one male. E.O. Wilson looked at pop genetics, evolution, animal behavior.
Reciprocal altruism has a delay until favor is paid back Altruistic behavior has no apparent payoff.
Hamilton pointed out that your genes can be passed on through close relatives, whose offspring will have some of the same genes. Kin selection is natural selection that increases inclusive fitness thru breeding success of close relatives. A prairie dog will raise out of burrow to give alarm call to siblings, even while placing herself in danger.