problem 4 Flashcards
(25 cards)
Kin selection
evolutionary strategy that favors the reproductive success of an organisms relatives, even at a cost to own reproduction/ survival
Hamilton’s rule
Kin selection causes genes to increase in frequency when the genetic relatedness of a recipient to an actor multiplied by the benefit to the recipient is greater than the reproductive cost to the actor (r*b > c)
inclusive fitness
Ability of an individual organism to pass on its genes to the next generation, taking into account the shared genes passed on by the organism’s close relatives
alloparenting
An individual other than the biological parent of an offspring that performs the functions of a parent
altruism
Selfless concern for the well-being of others – behaviour that benefits others at costs for the actor
mutual-benefit behavior
Behaviour that is beneficial both to the actor and the recipient (type of cooperation)
by-product benefits
Situations where the mutual benefit arises simply from every individual following its own immediate self-interest
direct reciprocity
we help individuals that help us (tit-for-tat)
indirect reciprocity
Help is given to individuals based on their reputation, bad acts (such as not helping) reduce an individual’s reputation while good acts (such as helping) increase an individual’s reputation
green beard effect
explanation of selective altruism among individuals of a species. Occurs when an allele produces 3 effects: a perceptible trait (the green beard), recognition if this trait by others, preferential treatment of individuals with the trait
eusociality
Highest level of organization of animal sociality, is defined by the following characteristics: cooperative brood care, overlapping generations within a colony of adults, a division of labour into reproductive + non-reproductive groups
(bees/ ants)
philopatry
tendency of an organism to stay in/ habitually return to a particular area
reproductive altruism
behavior that increases others fitness + permanently decreases own fitness
ultimate explanations
Why something occurs – “real” reason behind a behavior, concerned with the fitness consequences of a trait or behavior + whether it is (or is not) selected
proximate explanations
How something occurs, concerned with the mechanisms that underpin the trait or behavior
parochial altruism
Self-sacrifice to benefit our own group (“in-group love”) and to hurt or sabotage out-groups (“out-group aggression”)
grudger
always co-operates unless the other defects – then he only defects (he is pissed off)
tester
strategy starts of cooperating and then defects to see what the opponent does and to find out their strategy
network reciprocity
If a co-operator pays a cost, c, for each neighbor to receive a benefit, b, + defectors have no costs + their neighbors receive no benefits, network reciprocity can favor cooperation. The benefit-to-cost ratio must exceed the average number of people, k, per individual: b / c > k
group selection
describes natural selection operating between groups rather than between individuals
Multi-level selection = Selection on the lower level (within groups) favors defectors, whereas selection on the higher level (between groups) favors co-operators, b/c > 1+(n/m)
generous tit-for-tat
If the other cooperates, you cooperate – if the other doesn’t cooperate, you sometimes do not cooperate as well
stay-loose-shift
You keep your strategy as long as you win, if you lose, you change your strategy
prisoner’s dilemma
Situation in which 2 players each have 2 options whose outcome depends crucially on the simultaneous choice made by the other, often formulated in terms of 2 prisoners separately deciding whether to confess to a crime
reproductive restraint
adaption that has evolved because it increases likelihood of population surviving through bad years
