parental care Flashcards
parental care is a strategy to improve ____ success, depending on the conditions of their _____.
animal behaviourists evaluate parental care based on ____ to the parents and offspring.
reproductive; evolution
costs and benefits
parents can judge offspring by appearance or behavior.
what signals do offspring give?
- signal of need hypothesis
- signals advertise on offspring’s levels of need for care - signal of quality hypothesis
- signals advertise on offspring’s quality and condition
barn swallow chicks with redder mouths is an honest signal that they are of good __________. brightness may indicate ____. it shows that they are metabolising ____ from thier diets which is associated with enhanced ______ function.
condition; health; carotenoids; immune
in low quality, unpredictable environments
in predictable, high quality environments
match.
1) chicks in poor condition begged more, and parents responded more to those in most need.
2) parents paid less attention to begging and attended more to body size and signals of quality to choose who to feed.
1) chicks in poor condition begged more, and parents responded more to those in most need. - in predictable, high quality environments (food is abundant, can afford based on need)
2) parents paid less attention to begging and attended more to body size and signals of quality to choose who to feed. - in low quality, unpredictable environments (food is scarce, need to be more selective)
colored gapes not always signal ____, but also enhance _____.
offspring quality; visibility
in red mason bee, daughters have higher ___ value and are cared for better. the males are fed much less because they don’t need to ___.
reproductive; raise offspring
on average, sex ratio should be 1:1. but conditions can affect this ratio and reproductive value of each sex. what 2 hypotheses explain the skew in sex ratio?
- local competition hypothesis
related individuals compete for resources/mates, 1 sex is less valuable to produce - local enhancement hypothesis
1 sex provides resources or enhance mating success of its relatives, then that sex is more valuable to produce
on seychelles warblers.
in low quality environments where food is scarce, parents produce more ________ to ________.
in high quality environments where food is abundant, parents produce more ___________ due to __________.
keep __ around if can afford, and if not have ____.
males; reduce competition
females; enhanced offspring care
females; males
on seychelles warblers.
females are the primary ___ sex while males are the primary ____ sex.
helping; dispersing
what is the trivers-willard hypothesis?
mothers can adjust offspring sex ratio according to their own body condition
if male offspring has high reproductive skew, mothers in good condition will have more males and those in poor conditions will have more females
high sibling conflicts lead to________.
siblicide
obligate siblicide vs facultative siblicide
obligate siblicide is a fixed and essential part of the species’ survival strategy, while facultative siblicide happens only under specific conditions of resource limitation.
nazca boobies exhibit ____ siblicide while blue-footed boobies exhibit _________ siblicide.
obligate; facultative
what is reproductive insurance hypothesis?
additional eggs laid as insurance against failure of first egg to hatch
additional eggs laid as insurance against failure of first egg to hatch. what hypothesis is this?
reproductive insurance hypothesis
in egrets, mother birds lay 3 eggs asynchronously. the first egg has larger quantities of _____, increasing its __________.
last egg to hatch has the greatest likelihood to _______.
egrets exhibit ________ siblicide when parents permit it only when resources are ____.
androgen; combativeness
die
facultative; low
what is life history trade-off?
parental strategies not only take into account choice within a present situation, but also must relate to reproductive potential in future.
if parent cannot survive the current batch of offspring, it will lose out all future reproductive output.
parental strategies not only take into account choice within a present situation, but also must relate to reproductive potential in future.
if parent cannot survive the current batch of offspring, it will lose out all future reproductive output.
what is this concept called?
life history trade-off
birds in north america have shorter lifespan than those in the south. apply the life history trade-off concept.
birds in the south have longer life span –> greater future potential reproductive success. so they will minimise risk to themselves when attacked.
birds in the north will defend their offspring more heavily than themselves as their offspring have greater future potential reproductive success.
what is the paternity assurance hypothesis?
males are more likely to offer paternal care when there is higher certainty that they sired the offspring.
which species of frog show parental care?
poison dart frogs
female bats can discriminate their own young even in caves filled with them, ~4000 pups/m2. they use ___ and ___ cues.
olfactory; vocal
cliff swallows can learn to accurately discriminate pairs of nestling calls faster than barn swallow can. true or false?
true.
what is interspecific brood parasitism?
when one species lays eggs in another species’ nest
when one species lays eggs in another species’ nest, it is called ______.
interspecific brood parasitism
reed warblers will accept all eggs in their nest unless ____.
they see a cuckoo or its decoy nearby, then they wil reject the cuckoo egg but sometimes mistakenly reject their own egg
what is the mafia hypothesis?
host will accept brood parasites’ eggs to avoid retaliation by parasitic parents
host will accept brood parasites’ eggs to avoid retaliation by parasitic parents. what is this hypothesis called?
mafia hypothesis
female prinias discriminated egg difference by ___ and not ___.
color; pattern
state the gradualist shift hypothesis in parasitic cuckoos
interspecific brood parasitism evolved from intraspecific parasitism
most brood parasite specialists don’t target closely related species. The target smaller, unrelated species so their larger offspring are more ikely to be fed. in this case, they are exploiting ________.
sensory bias
in a study where blue tits and great tits were cross-fostered, blue tits were not successful in nests of great tits because they are ____. great tits were very successful in blue tits’ nests because they are ____.
smaller; larger
interspecific brood parasitism evolved from intraspecific parasitism - is this proven?
no. the closest relatives of obligate nest parasites are non-parasitic
