PSYC 3280 Lecture Notes - Lecture 3: Evolutionary Arms Race, Reciprocal Altruism, Cleaner Fish
4 Feb 2018
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Reciprocal altruism: helping non-relative strangers survive does not increase a person"s inclusive fitness, genes providing benefits to non-relatives will only evolve if these benefits will be returned in the future, symbiosis with a time lag. In ontario, nocturnal predation mostly by racoons: nest in marshes, return to same nesting site and defend territory, males often have same neighbors year to year, males will help defend the nests of neighbors by mobbing predators. Beletsky and orians (1989) washington: females preferred males with familiar neighbors, males with familiar neighbors had more offspring, males not very related to neighbors (male and female, thought that better ability to mob magpies was reason, reciprocal altruism. The problem of cheaters: cheaters that can take advantage of altruists would out-compete altruists. Cheaters will slowly become dominant, pushing altruists out of the population: for altruistic genes to be maintained, altruists need ways to detect cheaters. Evolutionary arms race : stable ratio of cheaters to altruists.
