The Problem of Altruism: paying a cost to benefit another decreases ones
own fitness while increasing anothers fitness
Inclusive Fitness: explains altruism towards kin.
Discriminative altruism directs benefits only towards others
who likely car
Females Invest More
Paternity Uncertainty Hypothesis:
Internal female fertilization>paternity uncertainty will be
strongest >before male (the father), female may have courtship
with other males, then the father may provide resources to whom
Parental Investment Theory
Robert Trivers (1972).
The sex that makes the smaller investment competes for the sex that makes the
o Males compete for females.
The sex that makes the larger investment will be choosier when selecting
Chapter 4-5 May 22nd & 27th
1. Why have sex?
- Red Queen Theory
2. Why have two sexes?
- Disrupted selection, there are only two specializations: size and quantity>have two sexes
will increase both size and quantity th
Lecture May 29th
Preferences of Homosexuals
Homosexual men are similar to heterosexual men:
Prefer youthful partners.
Care less about resources.
More likely to engage in casual sex.
Butch() lesbians have preferences simil
Chapter 10 Aggression & Warfare
Humans & Chimps: male-initiated coordinated coalitions for the purpose of raiding nearby
territories resulting in lethal attacks on members of own species. Only human and chimps
share this unique pattern of aggression. Bond