PSYC 472 Lecture Notes - Lecture 6: Parental Investment, Evolutionarily Stable Strategy, Polygyny Threshold Model
Document Summary
Fetal loss: e. g. eldest shark embryo that kills its siblings before they grow their teeth. Big eggs little sperm and differences in parental investment/amount of offspring produced in lifetime (in general females have more pi, but in many species males still do pi) Parental investment: any effort by a parent to increase the chances of survival of an existing offspring at the expense of the parent"s ability to produce future offspring. By this logic, more likely for e. g. older females because they probably won"t be able to produce offspring for much longer (last chance) In some species (e. g. emperor penguins), the mother"s pi alone cannot sufficiently provide for young, so male reproductive success is linked to their pi. Polygyny: 1 male, more than 1 female (fewer males than females) Polyandry: 1 female, multiple males (more females than males) For females: few gametes, each mating is a large percentage of rs, rs depends on percent of offspring raised to maturity.
