1. The Evolution of Helpful Behavior and Altruism

4. Mutualism Team of male lions, 2-3 members Lazuli buntings
Hunt together
Share access to females pretty equally
Going alone would not be as successful (cost-benefit)
Lazuli buntings
Dominant, bright colored males tolerate dull subordinate males in neighboring territories
Good territory for sharing of females

6. Reciprocity
Initial helpful action leads to a benefit later on when that helpful action is returned
Sentinel theory
Personal safety theory
Supported by more
observations than sentinel

7. Reciprocity in flycatchers
Birds observe their neighbors being “attacked” by stuffed hawks on both sides
They help mob the hawk attacking the neighbors that helped them in an earlier experiment
Detect attack, realize implications of attack, recognize neighbors that helped them earlier, decide to help those neighbors now, over the neighbors that did not provide help to them

8. Reciprocity in primates
Sharing ability of the actor, when he was paired with a trained altruist, who always pulled for him, and a “defector” who pulled randomly

9. Problems with reciprocity
Defectors take a free ride
Don’t repay helpers
Prisoner’s dilemma
Multiple interactions
hypothesis
Multiple interactions complicate
Silence=altruism, always better for the other person (cooperate)
Confession=selfish, always better for self (unless both confess) (defect)

10. Altruism and Indirect Selection
Theory relies on the passing on of ones alleles, which are shared with close relatives
Relatedness is key, as siblings>cousins>second cousins in terms of genetic similarity
Relatives fight each other less often, cooperate more often

11. DQ
If an altruistic act increases the genetic success of the altruist, then in what sense is altruism actually selfish? Words like “altrusim” and “selfishness” carry implications about motivation and intent…why might the everyday usage of these words get us in trouble when we hear them in an evolutionary context? If an individual inadvertently helped another at a cost of his own reproductive success, would such an action be considered altruistic in the evolutionary sense?
In the ultimate sense, the intent doesn’t matter at all

12. Relatedness dependent cooperation
Mothers brood eggs in the nest, males guard against intruders

13. Altruism in Belding’s ground squirrel
Alarm call to alert others of predator
Signaler does get killed more often
Altruism as direct and indirect selection: Females call more often when their offspring and/or nondescendent relatives are neighbors