Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

53 Cards in this Set

  • Front
  • Back
heat sensing in rattlesnakes
Use body heat to find prey – have organ on tops of their heads called “pits” that have cells sensory to heat

-orientation arena w/ hungry rattlesnake inside
-made point source of heat on outside of “arena” so snake could definitely not see it, total darkness
-snake struck at the wall of the arena within a few inches consistently near heat
shark detection of prey
-aquarium with shark in it, set up with sand in bottom, water flowing through tank into sand area
1) Bury live flatfish in sand – shark attacks immediately, finds and eats it 2) Buried dead flatfish (no electric fields) – shark first went where water was flowing out from the sand, then worked its way back until it found the fish – suggests sense of smell (carried by water)
3) Live fish wrapped in insulation (electric field blocked) – shark investigated outflow first
4) Buried set of electrodes in sand, no fish – shark went straight to the electrodes, suggests shark can detect electric field and use it primarily to find their food (smell is secondary)
blue jay foraging
optimality theories
Optimality – doing something the best way
-shaped through trial and error (learning) and evolution (natural selection)
- benefits - costs = net benefits
optimality in rufous hummingbirds
Migrate from Canada to Mexico
Cannot store enough body fat to make whole trip, so they find habitat in Mountains in mid California to feed
Birds change behavior while on these feeding grounds

Scientists observed birds and measured territory size
Captured bird at beginning of day and weighed them, let them feed all day, then measured weight at end of the day
territory weight
DAY 1 2000 m^2 0.2 g
DAY 2 3000 m^2 0.28 g
DAY 3 2500 m^2 0.4 g smaller territory size, more weight gain? Less flying around territory/energy spent defending it
**bird was optimizing territory size for maximum weight gain!!**

Optimum territory size changes every season, must be flexible for birds to maximize eating habits
optimality in crows
Problem – crows can often not fit food into their mouths or break shells
Crows grab shell, fly into air, drop whelks on rocks, shell breaks and they eat
Optimality – behavior should provide benefit and should be the BEST method

Scientists watched crows
Asked why crows always chose whelks of a certain size or bigger
Collected all the whelks on the beach and sorted them into small, medium, and large
Set these shells out in equal numbers and monitored beach every hour

START 70 70 70
HR 1 70 70 62
HR 2 70 70 50
HR 3 70 69 42
HR 6 70 67 3

Large shells obviously preferred
Crows passed over smaller shells even when larger ones were rare
Large shells had 25% chance of breaking on any particular drop
Pure chance, must land on certain angle to break
Dropped from 5m – consistent height
Small shell has to be dropped many more times – have not grown big projection that makes it more vulnerable to breaking
Scientists dropped shells from different heights
Shorter drops less effective, higher drops equally effective but take more energy to fly to
Benefit (calories gained from eating shell) – cost (calories spent handling the shell) = net benefit
Large whelks have positive net benefit, but medium and small have negative net costs – they are not worth it
nutritional constraints to optimality - moose
Constraints on optimality – keep animals from getting calories in the most efficient way
Make sure the animal is getting all the nutrition it needs
In meadow surrounded by grass, go to a stream to eat grass which is very low in calories
Provides moose with salt they need, then they move on to the higher calorie grass
nutritional constraints to optimality - squirrels
Eats pine needles
Prefers fresh green pine needles rather than old one, goes from branch to branch in trees eating fresh needles
Once fresh needles are gone, squirrel leaves tree and finds a new one – doesn’t always go to next nearest available tree – why?
Avoiding a toxin – alpha-pinene, found in pine needles, different quantities in different trees
Can smell or taste too much of the toxin in a tree, skip it over
nutritional constraints to optimality - jumping spiders
don’t build webs, hunt for insects and jump on them
Find area with many insects, eat on or two, and then move on – why would it not eat all of the insects in the one spot???
Scientists raised female spiders with different diets – one with variety of many insect species and one with no variety
Counted number of eggs that female spiders produced
Females that ate variety of insects produced more eggs
predation constraint - chacma baboons
Riparian habitat at bottom of rocky slope and short grass, on the other side there is dry riverbed
Monkeys sleep on rocky slope, every day they go through short grass and trees and feed on dry riverbed
Riparian habitat much higher productivity and closer – why don’t monkeys feed there?
LEAOPARDS – roost in trees of riparian habitat, easy to hide – predation risk very high
In dry riverbed, leopards are much easier to spot in time to escape
predation constraint - leaf-cutter ants
Use leaves of trees to stuff chambers in colony
Leaves rot, fungus grows
Ants put fungus spores on leaves and eat it
Farming their own food!
Constantly needing to replenish supply of leaves
2 kind of worker ants
Large – go out at night, much more efficient, can bring back larger pieces
Small – go out during the day
WHY does colony have smaller ants??
Parasitic wasp – find leaf cuter ants and injects egg into ant that eventually hatches and eats it from the inside out
Large workers are big enough to be used by parasitic wasp, but the small ones aren’t
Parasitic wasp only active during day – colony’s use of small ants during the day is a predation avoidance behavior!
predation constraint/risk management - Great tit
seed eater – can CHOOSE behavior depending on environment and risk
takes seed from feeder, goes away from tree to eat it
Stay near feeder until they believe it is unsafe
Take seeds to more sheltered areas
Can switch behaviors depending on proximity of predators
Have trained falcon fly over are and birds will send out alarm call and change behavior to fly to shelter

Trips to and from feeder take more energy, but keep birds safe from predators
predation consntraint/risk management - salmon
When they hatch, the find hiding holes to wait for prey (insects)
When they see prey, they zip out of holes, grab prey, and go back into hiding
Distance travelled to capture prey depends on value of the prey and risk of either being captured by a predator or being beaten by competition

Aquarium set up with rocks and baby salmon in hiding
Bugs dropped onto surface of water, salmon makes choice whether or not to go for it
Plotted size of prey vs. distance travelled by the salmon
The larger the prey, the more willing the salmon were to travel farther

Situation 1 – control
Situation 2 – held a picture of an adult brown trout up to glass where salmon could see it, repeated experiment
Salmon willing to travel shorter distances for same size prey
Took fewer risks when a predator was nearby
Situation 3 – help mirror to the glass (salmon thinks there is another salmon – competition), repeated experiment
Samon willing to travel LONGER distances for same size prey
Took more risks when there was a competitor present

CONDITIONAL STRATEGY – variety in behavior dependent on conditions of environment
frequency dependent selection in Perissodus
Frequency dependent selection – whether a trait is selected for or not depends on its frequency in the population

Two kinds of Perissodus fish – slant on left jaw and slant on right jaw
Population seesaws in terms of which type is dominant
If one is less dominant, it will have less competition, be more successful, and reproduce more
When one type is dominant, prey learns to protect that side, so the minority becomes more successful
Jaw slant is genetic
different circadian rhythms in drosphilia
Periodgene – controls the length of the time that a rhythm takes
Per+ - about 24 hours (orange)
Perl – about 27 hours (purple)
perS – about 19 hours (blue)
Per0 – null allele – doesn’t work at all, results in arrhythmia

TIDAL RHYTHM - fiddler crabs
Other rhythms besides circadian rhythms
Fiddler crab has tidal rhythm
-feed on tidal mudflats
-when tide comes out, crab crawls around on mud and gathers food
-stops feeding and goes back to burrow before tide comes back up
-How do they anticipate the return of the high tide?
>program of activity pattern that is tuned to the tides (about 12 ½ hours)

EXPERIMENT : crabs in lab put in aquarium with mud flat and water
-crabs dig burrows in mud
-after brought from the wild, crabs still showed tidal rhythm - lasted for weeks in the lab
-tidal rhythm they show reflects tidal pattern from the environment they were taken from
-tidal rhythms matched local patterns – suggests that rhythm can be tuned to local environmental cues
-entrainment – when internal rhythm matched external cues
Grunion – semilunar rhythm – half a lunar cycle long, dependent on tides fluctuation every two weeks or so (highest tide to highest tide)
-fish swim up onto sand to lay eggs on sand where they will not be covered with water for two more weeks
-when the water hits two weeks later, the eggs hatch and swim back out into the water
-protects eggs from predation in water

Neap tide – all tides remain relatively low
Spring tide – sun and moon create super high tide or super low tide

Two day window between spring tide and when tide reached point that it will reach again in two weeks
>this two day window used to lay eggs

This cycle generally used by animals who exploit the intertidal zone
LUNAR RHYTHM - kangaroo rats
-animals didn’t forage if there was a moon
-stripes in graph show inactivity in kangaroo rats due to moonlight
-seasonal effect – activity pattern goes away in late spring/summer when moon is set
-summer – active all say long
-switch from having lunar rhythm to nocturnal/diurnal rhythm to having no rhythm at all
> reflects availability of food? When food is more scarce, they risk foraging even in moonlight
-seem to be able to anticipate when moon is going to rise, don’t even come out of burrows
lunar/circannual rhythm - palolo worm
Palolo worm – long, segmented bodies
>for most of the year, their body ends at the wide, earthworm looking segment
>during mating season, they grow extra segment shown in picture
>this part breaks off and swims up to shore on its own, where it spawns – eggs and sperm are released

Problem – getting eggs and sperm to hook up in big wide ocean
Solution – all individuals spawn at the same time

Circannual rhythm – about a year long, season effect, hits when breeding season hits
>breed in South Pacific – October to December
Lunar rhythm
>spawn on day of last quarter moon AT DAWN (suspected to be circadian rhythm)
rhythms and entrainment - crickets
-to attract males, needs to sing at night when females are active
-needs to stop singing well before sunrise to give him time to forage for food

-male starts singing a couple hours before nightfall, stops a couple hours before sunrise

-If lab cricket is given 12 hrs of light and 12 of dark, he will sing the same time every day (bottom graph, approx 5 pm to 3 am)
-if given constant conditions – all day of light – line shift over
>EX : Day 1 – 5pm-3am, Day 2 – 6pm-4am, Day 3 7pm-5am
>singing for same number of hours, but the timeline is shifting
>cricket following own internal clock, which turns out to have a 25 hour day
-cricket’s endogenous rhythm = 25 hours, free running in this situation

Human beings:
-natural circadian rhythm about 25 hours long on average
*in the absence of environmental cues, the endogenous/free running rhythm runs a certain way; given the environmental cues the animal will tune its rhythm

Rhythm – comes from hormones?
-Short winged – active during day, mostly walk
-Long winged – fly more, active at night
-Bursts in activity correspond with bursts in JH

Entrainment cue for cricket’s rhythm = light
rhythms and entrainment - squirrel
Have to hibernate in the winter – must anticipate need to hibernate to be prepared when winter comes
Towards end of summer, start eating a lot and building up fat stores, prepare burrow, etc


Take baby squirrels and put them in lab environmental chamber
First cycle – go into hibernation around the same time, come out at about the same time
Feed/remain active all summer
Without any environmental cues, go into hibernation – individuals start to hibernate on their own schedule – these are their FREE RUNNING, ENDOGENOUS rhythms!

Another batch of squirrels were given environmental cues
Result – photoperiod is the entrainment cues that create natural rhythm
If it is warm, no hibernation takes place
rhythms and entrainment - green anoles
Male dewlap displays response to testosterone – testes regress in winter and grow back in the spring

Males – temperature increases in spring, triggers testes growth
Females – temperature increases had no effect on ovarian growth

Housed females either… and looked at ovarian growth
alone or slow
with females or slow
with males fast

One hypothesis – male making some sort of pheromone?
Another – social effect?

More experiments housed females in different situations
Female housed with normal male – fast ovarian growth
Female housed with castrated male (not producing testes) – slow ovarian growth
Female housed with normal male with removed dewlap – slow ovarian growth

Result – seeing courtship displays triggered ovarian growth in the female – visual signal and social cue
biological clock - bees
Time sense – rough ability to track passage of time

-set up feeding stations in random areas around a hive
>consisted of highly concentrated sugar water
>filled feeding stations at different times of day
-bees very good at remembering locations
-after about a week the bees had also learned which stations had sugar water at which times, accuracy within 15 minutes

-behvaior thought to be dependent on biological clock present in some cells
biological clock - silk moths
Giant silk moths – both have circadian rhythm, but timing and activity patterns are different

EXPERIMENT – tried to test circadian rhythm of pupal emergence
-in cecropia moth, animals emerged from pupal case to adult stage in the morning – right after sun rises
-in pernyi moth, pupas emerged just before sun sets
-Is there a biological clock, if so where is it????
1) removed brain of pupa – still went through whole process of emerging into adulthood, but there was no trend in time of emergence
>biological clock or something needed for it to function was destroyed
2) Transplanted brain to abdomen
>resulted in original emergence pattern
>necessary for biological clock – must be a hormone (brain has no neural connection while free floating in the abdomen, distributes hormone through blood) How does the brain know when to release hormone? What is the source of photosensitivity?
1) eyes detect light and cause release or hormone (unlikely because of rhythm functioning when brain was in abdomen)
2) brain itself has photoreceptors

Shone light on different parts of the moth’s body and observed the reactions
Put pupa in box with times lights, gave each side a different pattern
For example: Side 1 (Lights on 9am-9pm)
Side 2 (Lights on 9pm to 9am)
Normal pupa – emerged around 9 am, suggests photosensitivity located in head (eyes AND brain)
Transplanted brain of another pupa to abdomen – emerged just after 9 pm, suggests photosensitivity in the BRAIN
Control > remove brain and put it back in the head – confirms brain’s role (emergence just after 9am)

How to show that the timing mechanism itself was in the brain?
EXPERIMENT – took pernyi and cecropia and did a cross species transplant (put brain of one into the other and vis versa)
Results – moths emerged on schedule of other species (according to brain’s natural timing)
genetics behind biological clock in fruit flies
-Cells themselves have rough circadian rythms
-negative feedback loop – drosphila
>PERgene and TIM gene – together form complex that is a transcription factor
>as soon as there is enough of the complex, it turns itself off
>once the complex runs out, the genes are turned back on – endless loop
-cryptochrome – another protein
>light triggers cryptochrome > events that cause TIM protein to break down > no more complex (PER then becomes destroyed)
>as long as light is shining on the cell, there are no PERTIM complexes
>system works according to whether there is light or not
SCN - biological clock in rodents
SCN – located in hypothalamus, plays part in basic functioning
> when damaged animals often lose rhythms

Took hamster (nocturnal) and lab rat (usually diurnal)
-took SCN from fetal hamster and transplanted it into an adult rat that lacked its own SCN
-rat became nocturnal like the hamster

Cells of SCN – VERY strong rhythm, stronger than most other cells
Conditional Strategies: Ruddy Turnstone
Conditional strategy – NOT GENETIC
Individual alters its behavior based on what is working

Ruddy Turnstone: divide into 3 different types of behaviors
Dominant birds in the flock choose the seaweed – easiest food to get to!
Birds behavior based on social hierarchy
When top birds are taken away, the lower birds will move up
Strategy changes based on what’s available!
the art of blending in – usually a combination of appearance & behavior
examples - look at beginning of Ch 11 slides
distracting or lying to the predator

Blue tailed skink lizard
Has ability to break of tail
Tail is bright blue, wiggles and moves on forest floor, while the rest of the lizard motors away and escapes

Hognose snake
Cryptic – blend in with forest floor
If crypsis fails, have misdirection method
Roll over onto back displaying belly and dislodges jaw to open mouth super wide, wiggles
Startles predators, such as dogs, often won’t attack
When even THIS isn’t effective, snake just flops and plays dead – looks more like rope
Movement often make predators more likely to strike, so this is effective
inflating size
convincing the predator that you are bigger & meaner than you really are

owl butterfly:
Butterfly rests with wings folded
When bird shows up, butterfly opens wings it opens wings and looks like much bigger animal, such as an owl
Birds don’t want to rick owl predation, fly away

Female own at nest
can’t leave because she can’t leave nestlings
Spreads wings out, looks much bigger
Aposematic characteristics
showing the predator that you are dangerous
ex: warning coloration in frogs, skunk
innate avoidance of warning coloration - kiskadees
Innate avoidance of coral snakes (which are poisonous)
Presented kiskadees that had never encountered coral snakes with painted rods similar to different creatures
Avoided the snakes
learned avoidance - blue jay
EXPERIMENT: learned avoidance
Monarch butterfly and naïve blue jay
Blue jay offered monarch butterfly, eats it, then throws up
After this, blue jay never accepted/attacked another monarch butterfly

Why do some animals have such innate mechanisms?
Kiskadees evolved in area with coral snakes – avoidance likely selected for
Environments of blue jays and monarchs environments overlap less, avoidance needed to be learned
Batesian Mimicry
pretending you are dangerous
batesian mimicry - monarch butterfly and viceroys
Monarch butterflies are toxic
Costly biochemical process to eat these toxins and store them
Viceroy butterflies don’t have ability to eat these toxins, but they have coloration much like monarch’s warning coloration
LOOKS LIKE it’s poisonous
Most birds won’t eat viceroy’s because they know not to eat monarchs
batesian mimicry - king snake and coral snake
Coral snake vs. king snake – different patterns of coloration
- King snake safe, but has same scary black yellow red coloration

What about king snakes in places without coral snakes?
Made plasticine models
Left it in nature for a week, counted teeth marks
Had brown, cryptic models, kingsnake patterned models, and longitudinal stripes of same colors
Did experiment in North Carolina (coastal plain vs piedmont) and Arizona (low elevation vs. high elevation)
Had people who had no idea which regions they were from count the teeth marks in rods
Brown cryptic rods – attacked equally in all areas
Kingsnake pattern – attacked more in areas with no coral snakes
Longitudinal – attacked only slightly less in coral snake areas vs no coral snake areas, and less than kingsnakes in no coral snake areas
advertisement - gazelles
Gazelle – behavior called stotting
Gazelle starts bouncing when it spots a predator
Very conspicuous, they do it whether they are by themselves or with the rest of the herd
Does this so cheetah knows the gazelle sees it and will run away
Basically saying “There’s no use, I see you, don’t even bother”

Hypotheses and predictions:
Alarm signal: should not stot alone
Social cohesion: should aim display to other gazelles
Confusion effect: should not stot alone
Pursuit Deterrence: predator should stop the chase
size, armor, and weaponry
ex: elephant, crayfish, elk
hiding places
-first defense is crypsis
-vulnerable to predation, especially by birds
-when they feel threatened, they run into a crevice and begin to swallow air – become so wedged into the crevice that nothing can pull them out
-when they feel safe again, they let out a giant burp and can exit the crevice

-Use burrows/dens to protect babies
-very vulnerable to lions
social defenses: dilusion effect
safety in numbers alone (flocks of birds)
social defenses: confusion effect
-When school sees predator, they create fountain or just swim all different ways
-because the predator cannot choose a target, it rarely gets one
-OR, target switching – manage to pick a target and aim for it, but another fish swims past and they get confused
social defenses: vigilance effect
-many eyes are better than just two
-when many animals are looking for predators, it is safer than just one looking for predators

Experiment: starlings in an aviary
-constructed clothing line over the aviary with pulley system
-dragged “predator” over aviary to see how soon birds noticed it
-When there were more birds, each one spent less time in vigilence (and more time eating) AND reaction time was faster

Goshawk success rate in hunting – MUCH lower in larger flocks
-being in flocks provides some protection
-could be confusion effect, vigilance effect, or something else?

Measure reaction distance
-in larger flocks, single birds were rarely caught because they were rarely taken by surprise
social defenses: cooperative protection
-when threatened by a pack of wolves, adults form shoulder-to-shoulder wall with young protected inside
-if wolves try to penetrate, they are kicked

Other type of behavior – mobbing behavior
-smaller birds call attention of larger birds to help get rid of larger predator
types of animal travels
Foraging trips
To and from a den or nest
Along a regular route with no set den
“Natal Dispersal”
“Post-breeding Dispersal”
Seasonal migrations
dispersal restlessness - screech owls
-parents chase away the young so as to have enough food in their territory
-biological rhythm – do this automatically

Experiment: in the field
-identified owl nests and fitted baby owls with radio transmitters to keep track of where they went
-at first, owls stayed very close to home, fly out every night and come perch right where parents nest was before dawn
-gradually travelled longer distances, didn’t return after 50 days
-moment of natal dispersal

2nd experiment: isolated in laboratory
-raised owls in lab in enclosures
-fitted each with pedometer and examined activity
-each owl showed increasing activity with age, peaked at 50 days then came back down
-biological rhythm – same activity evident when social interaction/parental influence were removed
-dispersal restlessness
why migrate?
Allows exploitation of new habitats
Reduces competition at home
STORY: Dispersers led to short-range migrants who developed (1) navigational abilities and (2) tendency to move from one region to another to exploit short-lived conditions. Short-range migrants set the stage for evolution of long-distance migrants.
reducing cost of migration
birds flying in V's - preserves energy
conditional strategy
migrate only if you have to

European blackbirds migrate if they cannot expect to get enough food; this depends on SOCIAL STATUS which usually reflects age
This is a Conditional Strategy
sun compass - european starling
-trained bird in circular bin to go to SW bin for food
-Used mirrors to create a “false sun” 180 degrees away from where it normally would have been
-Bird looked for food in NE bin

Clock shift experiment:
-birds must pay attention not only to sun position but also to time of day (because sun “moves” through sky)
-E (6 a.m.) SE (9 a.m.) S (12 p.m.) SW (3 p.m.) and w (6 p.m.)
-Suppose lights on at 3a.m. real time and off by 3p.m. If we test at 9a.m. real time, what direction should it go if using a sun compass?
-Bird time will be 12 noon, thinks the sun will be located in S – will look for food so many degrees west of where the sun is
star compass - indigo bunting
1)Normal sky – S
2)180 degree rotated – N
3)Clockshift – S
4)Without north Star (not moving through sky) – S
5)Removed whole North Pattern (cluster of stars that make very small circle) - random
Asymmetry in Resource Value of a territory: eggfly butterfly
Territory holder – or RESIDENT – has an advantage

Why is this?
-In some cases, is more familiar with territory and can use this to advantage
-Territory could be more valuable to the resident than it is to the intruder
-The longer an individual has been on it’s territory, the bigger advantage that is seen
-established relationships
-doesn’t have a lot to lose by fighting hard for his territory – is older, doesn’t have to worry about future reproductive fitness
-younger animal has more to lose in a fight in terms of reproductive fitness
-if he loses the territory, he’s probably not strong enough to find another

In this graph:
Paired butterflies of different ages with fresh new intruders
The older the butterfly was, the longer he was willing to fight for his territory

COST always taken into account in any battle – reproductive fitness, ability to avoid predators, energy reserves, etc
dear enemy hypothesis - fiddler crab
Fiddler crabs live on mudflaps, repel intruders from territories
-often, if one crab is involved in a territorial dispute, its neighbors will come to its aid
-researchers looked at issues such as location and size of helping crabs
**the helper crab is usually bigger than the intruder, which is bigger than the resident crab
-the bigger crab is helping the smaller crab because he’s not such a bad enemy to have close to him – the crab is small enough to not be a threat
-a new, bigger intruder, is a potential more relevant enemy

DEAR ENEMY HYPOTHESIS – resident crab is an enemy, but a less bad enemy, and one more well known
Speckled Wood butterfly – arbitrary asymmetry or RHP assessment?
Fly around searching for shafts of sunlight, when they find one they claim it for courtship territory
-possibly makes them more visible
-If another butterfly comes around and sees a male displaying, he will go away
-First come first serve? Intruder never challenged resident

Experiment – released one butterfly into shaft with another

-removed white butterfly with net and allowed black butterfly to become the owner
-rereleased white butterfly back
-white butterfly would try to fight, but usually lost
-supported hypothesis that OWNER ALWAYS WINS

-If kept in a box, instead of a net, the original owner almost always won

Look at physiology of the butterfly – cold blooded, don’t move as well when they are cold
-Butterflies kept in warmer boxes always won

-The reason the original owners don’t even get challenged is because they are already warmed up!!!!!!!