Behaviour and adaptation Flashcards
proximate vs ultimate explanation
- define
proximate = immediate explanation for a behaviour
ultimate = evolutionary significance of a behaviour
proximate vs ultimate explanations
- inbreeding avoidance
proximate
= general behaviour that avoids inbreeding
e.g. don’t mate with those you shared a nest with
ultimate
= avoid deleterious recessive phenotypes
why do orgs avoid inbreeding?
avoids combinations of deleterious alleles
- need to produce successful offspring that can pass on genes
hunting example
- facts
cheetahs hunting impala
C short bursts of up to 100km/hr
I top speed ~60km/hr
only 10% cheetah hunts successful due to short bursts and not as agile
hunting example
- selection predictions
- why?
should favour high speed in BOTH cheetah + impala
fastest cheetah should have highest fitness
slowest impala should have lowest fitness
hunting example
- why might we NOT see these predictions?
no variation in traits
- e.g. all run at same speed
variable running speed but NO heritable component
- determined by enviro = not affected by selection
speed may not be main component to success
- e.g. stealth + agility needed to chase zig zagging prey
trade offs
- fastest cheetahs exhausted after hunt = more vulnerable to predators
coloniality
- facts
many birds breed in colonies
- can be up to 1M in 1 colony
can reach high densities <40nests/m2
coloniality
- hypotheses for why
protection from predators
increased foraging success
coloniality example
- Black-headed gulls
protect the colony from crows
- nests inside colony protected more than those on outside
correlation suggests higher probability of a crow being attacked by a gull inside the colony
-> lower % of successful predation
coloniality
- predators
- prediction
colonies attract predators
- some colonies more vulnerable than others
depending on the enviro, will be susceptible to different predators
exposure to predators influences egg camouflage and the behaviour of adults + chicks
coloniality predator example
- nests
exposed nests e.g. black-headed gull on ground
- camouflaged eggs
- eggs shaped to maximise incubation efficiency
protected nests e.g. bald eagle on steep cliffs etc.
- eggs not camouflaged
- eggs shaped to not fall out nest
coloniality predator example
- chicks
exposed chicks
- camouflaged
- wander around nest
protected chicks
- not camouflaged
- stay in nest
coloniality predator example
- adults
exposed nests
- remove egg shells immediately after hatch
protected nests
- egg shells NOT removed immediately
why are egg shells removed by parents?
white inner of eggs makes nest conspicuous
= attracts predators
phylogenetic inertia
- define
- how does this affect taxa?
if your ancestors had a trait
-> likely you will too
related taxa likely to have similar traits due to phylogenetic inertia
.:. those taxa aren’t independent observations of the trait