experiments Flashcards
Observational Study: Elephant Ethogram
What behaviors to captive Asian elephants exhibit?
- every 5 minutes for 1 day for a week for 11 months – observed elephants behavior
- they show stereotypical behavior of spending 1/4 of their time eating (boredom)
- clumped vs. spaced feeding sights
- less bored when paced out
Observational Study: Why do crab eating macaques use special sleeping trees
- not a food source
- no evidence for predator avoidance
- an explanation was that they slept in trees opposite to other groups
- advertisement theory supported
Spallanzani’s 1st experiment
owls in complete darkness
- owls could not fly well
C - owls need sight for light
Spallanzani’s 2nd experiment
bats in complete darkness
- bats flew fine
C- bat’s don’t need sight for flight
Spallanzani’s 3rd experiment
black hoods on bats
- black hooded bats couldnt fly
C- bats need sight for flight
Spallanzani’s 4th experiment
transparent hoods on bats
- clear hooded bats couldn’t fly as well
C - hood was trouble whether or not light got in
Spallanzani’s 5th experiment
blind bats without covering ears
- flew just fine
C - bats don’t really need sight for successful flight
Spallanzani’s 6th experiment
plug ears wtih grease or cotton
- deadened bats couldnt fly well and didnt feed
C - bats need good hearing for successful flight
Spallanzani’s 7th experiment
control
deafened bats were distressed by objects in ears, placed hollow brass tubes
C - need good hearing
Hilara maura
gift wraps…random object
Hilara sartor
gift wraps…nothing at all
hilara quadrivattata
gift wraps dead prey in silk (to make it look bigger)
hilara thoracica
large cocoon, small prey
Trinidadian Guppies
upstream: low predation
downstream: high predation
– look different/diff puberty
Experiments: 200 guppies from high-predation site transferred upstream to low-predation sight
Result:
In 11 years (30-60 generations), the manipulated population evolved schooling and predator inspection behaviors more similar to the ancestral population
Fixed Action Pattern - Triggering Territorial behavior in Stickelbacks
- As long as the models had an eye and a red belly → could get them to show the territorial behavior
Experiment doesn’t suggest that they don’t react unless there is color → only tested gray/red
Fixed Action Pattern - Grey Goose’s Egg Retrieval
All female gray goose have egg retrieval
Whenever she notices that an egg is not in the nest – she uses her beak to roll it back to the nest
Was described originally as the mother’s love for the baby – but soon discovered it was a deep rooted behavior
- every female goose did this behavior in the same way
Stickleback Courtship behavior (Chain Rxn - FAP)
- female with eggs
- make responds with zigzag swim
- female follows
- male shows nest entrance and female enters nest
- male then prods females tail while making tremblig movements
- female spawns and leaves; male then enters the nest and also spawns
Tinbergen
Manipulation of environment to understand mechanism
(DIGGER WASP)
Digger wasp - visual cue changed (pine cones were no longer circled around the burrow)
returning wasps followed the visual cue: first searched firs in area with pine cones
Digger wasp - cue conflict vs. scent vs. vision
returning wasps followed the visual cue: searched first in area with pine condes
Begging in Black -headed gulls (4 steps)
1.) Chick approaches parent
2.) opens and closes beak several times
3.) chick turns its own head, positions own bill and graps parent’s bill
4.) chick pushes up with body and pulls down bill
Black-headed gulls experiment
- raised some chicks in incubators with no chance to properly beg, other chicks were raised normally
result: both sets did steps 1&2, but almost none of the incubator babies did steps 3 and 4 properlly
conclusion: 3&4 are nurture and 1&2 are innate
Stabilizing Selection in Cichlid Fish
wanted to compare growth rate of fish in different-sized patches of food
- focal fish trying to defend its food patch from 4 competitors
When measuring defensive behavior – defending larger territories required more work (more chases per minute)
When measuring growth rate of fish defending the different sized patches - medium sized territories had the best balance of cost and benefit
So: stabilizing selective pressure for intermediate territories
Directional Selection in Hawaiian Crickets
between 1991 and 2001 – sound of crickets almost disappeared
WHY - parasitic fly appeared and would listen for cricket calls then lay its eggs on the back of cricket for maggots to attack and eat
- downside to being a calling male cricket (sexual selection – females still prefer calling males)
- rapid evolution (directional selection) for crickets to become quiet – a mutation caused males to lose the sound-producing parts of their wings (did not get attacked and survived better)
What about Sexual Selection
- silent males would hang around calling males and try to intercept females
- silent males evolved to move around more
- females evolved to be less picky