Altruism (exam 2) Flashcards
Altruism
Genetically, increaseing fitness of another while decreaseing fitness of an individual
Group selection
altruism between a group thats not related
prisoner’s dilemma / Cooperation theory
Over long term, fitness is maintained or improved through cooperation
Kin selection
altruism in a group of related organisms
Inclusive Fitness
Fitness based on either personal reproductive success or that of individuals that carry copies of genes
Coefficient of relatedness, r
Identical twins 1.0
Parent,child 0.5
Full siblings 0.5
Half siblings 0.25
Uncle/aunt,niece/nephew 0.25
First cousin 0.125
Hamilton’s hypothesis
Genes for altruism can increase frequency if
benifit / cost > 1/r
benifit / cost definition
number of saved relatives / percent of likly death
1/r definition
1 / r of related individuals
“Helpers at the nest”
delayed, deferred reproduction while assist in rearing of full, half sibling’s (altruism example)
Eusociality
species produce non reproductive members to care for the reproductive member/s (insects)
Haplodiploidy and eusociality
-males are haploid, and females are diploid
-Non-reproductive worker sister serves reproductive queen
-Sister/sister r > mother/daughter r
-Fitness increases by rearing more sisters (r=0.75)
Naked mole rats and eusociality
-Queen and 2-3 repro males breed, care for young
-Large non-breeders dig
-Small non-breeders transport food
Biological species (2)
-group of individuals of a species that occupy a definded area
-bounderies determined by an ecologically relevent change in enviroment
Evolutionary species
-group of individuals of a species that mate at random
-bounderies determined by the barriers to mating and gene flow
