Sociobiology Flashcards
3 components of sociobiology
Biology
Ethology
Ecology
2 books of sociobiology
Wilson– Sociobiology: the new synthesis (1975)
Dawkins– The selfish gene (1976)
What is sociobiology concerned with
Contribution of behavioral traits to fitness
6 advantages of sociality
Mating and care of young Group defence against predation Foraging and cooperative hunting Manipulation of environment Division of labor Learning through cultural transmission
Why does altruism challenge sociobiology
Putting oneself at risk to help another reduces fitness. Evolution should select for selfishness over altruism
VC Wynne/Edwards
Dispersion and its relation to social behavior. Animals should avoid overexploitation of habitat by regulating birth rate
Carrying Capacity
Amount of animals a habitat can support
4 pieces of evidence for VC Wynne/Edwards
Animals capable of having way more babies than they do
Social subordinates dont reproduce in favor of dominant
Breeding stops after reasonable age
Parents sometimes consumer their own offspring
Group Selection Theory
Overpopulation avoided by altruistic restraint on reproduction for group benefit
Epideitic displays
Communal displays, roosting aggregations, group vocalisations. Provide population density info that regulates reproductive efforts via hormones
Problem with group selection theory
How does a gene that educes its own representation in the next generation survive in a gene pool
Empirical finding to support group selection theory
Reproduction adjusted t produce max number of surviving offspring. Appears sub-maximal but is actually optimal. English swift have more surviving fledglings when only 2/clutch are born
3 other explanations of altruism
Triver reciprocity theory
Alexander parental manipulation
Nowak multilevel selection
Kin Selection theory
Animals only care for others offspring if they are genetically related. Altruism according to genetic relatedness
Darwinian Fitness
Personal fitness–> how many offspring you produce
Inclusive Fitness
Net gene representation in succeeding generations. Indirect fitness
Altruism will occur if (equation thing)
K= ratio of recipient benefit to altruistic cost
R= coefficient of relatedness
K> 1/r
Hamiltons rule
r> c/b
OR
rb> c
Bird helping equation
H= # of helped siblings brought to maturity beyond parents capacity
S= # of siblings raised without help
For selection to favor helping H> S
Eusocial insects
Sterile females sacrifice reproduction to work for the reproductive success of their mother the queen