chapter six: adaptations for survival Flashcards
the hereditary trait most favored by natural selection
adaptation
an adaptation is the ____ option in the population
absolute best
number of your genes present in the next generation
fitness
predators are being selected for ____
their ability to catch prey
prey are being selected for ____
their ability to escape predators
different selective pressures on predators and prey lead to ___
co-evolution
mice stick beetle’s butt down into the earth and eat the beetle head down because _____
the beetle’s anti-predator defense is to spray the predator from its butt
evolution does not produce ____
adaptive perfection
three reasons not to expect adaptive perfection
- failure of a mutation to appear (can’t adapt if mutations never arise)
- pleiotropy
- co-evolution
pleiotropy refers to a gene that has ____
multiple effects
fitness benefits must be ____ than fitness costs for a trait to be considered adaptive
greater
costs of mobbing
risk of predation, using up energy
benefits of mobbing
scare away predator from nest
hypothesis for the purpose of mobbing?; is it supported?
it is an anti-predator behavior; supported
if mobbing is adaptive, you should see it when ____ > ____, which would be when predation is ____
benefit > cost
high
when two different lineages acquire the same trait with no common ancestor
convergent evolution
ancestors have a trait that a current species no longer has
divergent evolution
the best option will increase in a population as other options decrease
optimality theory
optimality theory says that species should optimize ______
benefits and cost
the best choice for an individual depends on what others are doing
game theory
Adelie penguins don’t want to be the ____ or ____ to jump in the water; this is an example of ____
first or last
game theory
an anti-predator strategy that includes simply not being seen
avoid detection
in order for camouflage to be effective, which four things are important
- color
- pattern
- orientation
- location
a second method to avoid detection is to remove _____
evidence that you are there/were there; hiding
how do the skipper butterfly larvae avoid detection
explosively eject fecal pellets to avoid being detected by scent
____ is easier detected than just ____, so to avoid detection many animals will ____
motion
being still
freeze
what is the most common anti-predator strategy
avoiding capture
how close a predator can get before the prey will flee
critical distance
why will prey wait on a predator to get within the critical distance instead of fleeing before that?
it wastes energy to run if you don’t need to
critical distance for lizards is based on _____
temperature
when it is colder, the lizard’s critical distance ____, when it is warmer it ____. why?
increases (run sooner)
decreases (run later)
they can’t move as fast in the cold
animals can also ____ an attack, mostly with ___ cues
misdirect
visual
false ____ on animals direct attention away from their ___
eyespots
head
animals can also make the predator ____, normally with a ___ or ___ cue
hesitate
visual or acoustic
some animals will play ____
dead
the ____ snake plays dead
hognose
some animals will fight a predator with ___ or ___ defenses
physical or chemical
physical defenses include ___ and ___
horns and hoobes
chemical defenses include ___ and ___
bad taste and venom
when a blue jay eats a monarch, it ____ and will ____
immediately throws up because of the toxicity and will never eat another butterfly that even resembles a monarch
predators have either ___ or ___ aversions to warning coloration of prey
learned or innate
mimicry only works if ____
toxic species outnumbers the nontoxic species
animals can avoid capture by associating with ____
protected species
can associate with species by ___ or ___
proximity or recycling chemical defenses
___ associate in proximity with ___
clown fish
sea anemone
hedgehogs harvest ____ that they then rub on their fur
toad venom
animals can avoid capture by showing that they are difficult to ____
catch or eat
pufferfish ___ so they look difficult to eat
blow up
what is stotting
gazelles will randomly jump upward while standing in a field
stotting is an ____ for fitness of gazelles
honest signal
gazelles who stot show predators that they are ____
strong and hard to catch
Anole lizards _____ is an honest signal
pushup display
animals can also make capture _____
less likely
prey species tend to be ___ and ___, why is this advantageous?
wary and easily spooked; they need to be this way to watch out for predators
animals can make capture less likely through ____ defense
social
social defense involves associating with ___ or ___
a different species or conspecifics
two advantages of associating with a different species
- more eyes watching for predators
- can respond to other species alarm signals
4 advantages of associating with conspecifics
- confusion effect
- mobbing
- group defense
- dilution effect
everybody moves in a different direction, hard for predator to hone in on one and attack
confusion effect
helping each other fight back
group defense
everybody hatches out at the same time and overwhelms the predator with more food than they can possibly eat so some or most will survive
dilution effect
example of dilution effect
mayflies all emerging in May, those that emerge later in the week are more likely to survive because predators are full
