IB 329 EXAM 3 QUESTIONS WITH VERIFIED ANSWERS
what are the types of investment - Answers - -protection from predation
-protection from elements
-provisioning/feeding
why is parental care costly - Answers - time, energy, and vulnerable to predation
bigger gametes - Answers - increase zygote size and survival
more gametes - Answers - increase potential number of offspring
time spent caring for offspring = - Answers - less mating opportunities
who has greater cost for parental care - Answers - males
increased investment = - Answers - =increased probability of young survival
=increased fitness for parents
life history traits - Answers - characteristics of an individual that influence survival and
reproduction
operational sex ratio - Answers - ratio of sexually receptive males to receptive females
(females limited by number of eggs, gestation, so ratio often male biased)
male biased parental care - Answers - eggs attach to male body until they hatch - male
burden
caring for wrong offspring - Answers - it is not worth it to care for wrong offspring -
communal care of offspring common in some species that live in groups
sibling aggression and siblicide - Answers - occurs when resources are variable or in
short supply
can parents control sex of offspring - Answers - haplo/diploid organisms:
fertilized=female, unfertilized=male
Temperature dependent sex determination: many reptiles
vasopressin - Answers - receptor gene that makes species monogamous and males
exhibit parental care
mechanisms of parental favoritism - Answers - differential feeding/care
number of eggs/size of litter
hatching order/asynchrony in hatching
, sex of offspring
benefits of juveniles staying to help second nesting effort - Answers - Direct (learning
about maternal care, inherit resources)
Indirect (inclusive fitness by helping related offspring)
Inclusive fitness = - Answers - Direct fitness (own reproduction) + indirect fitness
(relatives reproduction)
why does inclusive fitness matter - Answers - we share more genes with our relatives
than w/ population at large so by helping relatives we pass on those genes that we
share
Hamilton's Rule - Answers - Cooperation is favored when: rB - C > 0
r=relatedness between altruist and recipient
B=fitness benefit to recipient
C=fitness cost to the altruist
reproduction skew - Answers - the distribution of reproduction across members of a
group
high skew vs low skew - Answers - high= one or few individuals reproduce
low=everybody reproduces equally
dominants - Answers - control who breeds
subordinates - Answers - control whether they stay or go
reproductive skew should increase with - Answers - greater ecological constraints on
reproducing alone, higher relatedness, and low individual fighting ability
staying incentives - Answers - subordinates get a share of reproduction for not leaving
peace incentives - Answers - reduce aggression toward dominants for a share of
reproduction
benefits of sociality - Answers - pooled resources/shared defenses, division of labor,
increase indirect fitness (by helping relatives reproduce)
costs of sociality - Answers - shared resources, parasitism/disease, cheaters
dispersing costs - Answers - costs: risky, death, finding resources, finding mate
risks of not dispersing - Answers - competing with relatives
limited resources
inbreeding
what are the types of investment - Answers - -protection from predation
-protection from elements
-provisioning/feeding
why is parental care costly - Answers - time, energy, and vulnerable to predation
bigger gametes - Answers - increase zygote size and survival
more gametes - Answers - increase potential number of offspring
time spent caring for offspring = - Answers - less mating opportunities
who has greater cost for parental care - Answers - males
increased investment = - Answers - =increased probability of young survival
=increased fitness for parents
life history traits - Answers - characteristics of an individual that influence survival and
reproduction
operational sex ratio - Answers - ratio of sexually receptive males to receptive females
(females limited by number of eggs, gestation, so ratio often male biased)
male biased parental care - Answers - eggs attach to male body until they hatch - male
burden
caring for wrong offspring - Answers - it is not worth it to care for wrong offspring -
communal care of offspring common in some species that live in groups
sibling aggression and siblicide - Answers - occurs when resources are variable or in
short supply
can parents control sex of offspring - Answers - haplo/diploid organisms:
fertilized=female, unfertilized=male
Temperature dependent sex determination: many reptiles
vasopressin - Answers - receptor gene that makes species monogamous and males
exhibit parental care
mechanisms of parental favoritism - Answers - differential feeding/care
number of eggs/size of litter
hatching order/asynchrony in hatching
, sex of offspring
benefits of juveniles staying to help second nesting effort - Answers - Direct (learning
about maternal care, inherit resources)
Indirect (inclusive fitness by helping related offspring)
Inclusive fitness = - Answers - Direct fitness (own reproduction) + indirect fitness
(relatives reproduction)
why does inclusive fitness matter - Answers - we share more genes with our relatives
than w/ population at large so by helping relatives we pass on those genes that we
share
Hamilton's Rule - Answers - Cooperation is favored when: rB - C > 0
r=relatedness between altruist and recipient
B=fitness benefit to recipient
C=fitness cost to the altruist
reproduction skew - Answers - the distribution of reproduction across members of a
group
high skew vs low skew - Answers - high= one or few individuals reproduce
low=everybody reproduces equally
dominants - Answers - control who breeds
subordinates - Answers - control whether they stay or go
reproductive skew should increase with - Answers - greater ecological constraints on
reproducing alone, higher relatedness, and low individual fighting ability
staying incentives - Answers - subordinates get a share of reproduction for not leaving
peace incentives - Answers - reduce aggression toward dominants for a share of
reproduction
benefits of sociality - Answers - pooled resources/shared defenses, division of labor,
increase indirect fitness (by helping relatives reproduce)
costs of sociality - Answers - shared resources, parasitism/disease, cheaters
dispersing costs - Answers - costs: risky, death, finding resources, finding mate
risks of not dispersing - Answers - competing with relatives
limited resources
inbreeding
