Chapter 16: The Evolution of Behavior

Question 1

behavioral ecology

Answer 1

the science that explores the relationship between behavior, ecology, and evolution to elucidate the adaptive significance of animal actions

Question 2

individual selection

Answer 2

differential performance (fitness) of individuals causes some genotypes to outcompete and replace other genotypes

Question 3

group selection

Answer 3

differential performance (fitness) of groups of individuals causes some groups to outcompete and replace other groups

Question 4

game theory

Answer 4

a mathematical approach to studying behavior that solves for the optimal decision in strategic situations (games) where the payoff to a particular choice depends on the choices of others

Question 5

dilution effect

Answer 5

the safety in numbers that arises through swamping the foraging capacity of local predators

Question 6

altruism

Answer 6

occurs whenever a helping individual behaves in a way that benefits another individual at a cost to its own fitness

Question 7

inclusive fitness

Answer 7

an individual’s total fitness, including its own reproduction (direct fitness) as well as any increase in the reproduction of its relatives due specifically to its own actions (indirect fitness)

Question 8

kin selection

Answer 8

selection arising from the indirect fitness benefits of helping relatives

Question 9

green beard effect

Answer 9

a situation in which an allele (or a linked suite of alleles) produces three things: a recognizable phenotypic trait (the “green beard”), the ability to recognize this trait in other individuals, and preferential treatment of individuals with the trait

Question 10

coefficient of relatedness (r)

Answer 10

probability that the homologous alleles in two individuals are identical by descent; get it by looking at a pedigree; an allele for altruism will spread if the benefit is greater than the cost as in Br - C > 0 and the participants are closely related

Question 11

weaning conflict

Answer 11

occurs when parents want to stop investing in current offspring to be able to better provide for future offspring, ends when both sides agree that parents are better off investing in future offspring and the benefit to cost ratio drops off to below .5; weaning conflict lasts longer with half siblings because current offspring are less closely related to future offspring

Question 12

reciprocal altruism

Answer 12

being nice to non-relatives because you expect something in return in the future; quid pro quo