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Flashcards in optimal behaviour Deck (15)
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1
Q

what is the optimal foraging theory?

A

Foraging maximises the rate of obtaining energy

2
Q

marginal value theorem

A

a theorem that postulates that foraging animals should use the information at hand to predict the future value of a resource and to quit when that value reaches a level that makes the current behaviour no longer worthwhile

3
Q

trade off between foraging and vigalence

A

foraging: gets more energy
vigilance: won’t get eaten

4
Q

what does the marginal value theorem assume

A
  • environment consists of patches containing energy

- takes ‘fixed time’ to move between patches

5
Q

what does evolution increase?

A

survival value in a constant environment

6
Q

caveats

A

Behaviour may not be optimal if the environment changes

Animals are subject to constraints, e.g. information about environment, ability to move

7
Q

rate of getting energy

A

energy obtained from patch/ travel time + time in patch

8
Q

cowie experiment

A
  • mealworms in plastic cups on a tree in the experimental aviary
  • wild bird put in aviary one at a time
  • lids on cup to increase travel time
  • 2 treatments: short travel or long travel
9
Q

kacelnik experiment on starling

A
  • central place foraging theory

- starling goes to get food and returns to nest

10
Q

milinski and heller experiment and conclusion

A
  • sticklebacks eating water fleas (Daphnia) either with or without a model predator.
  • in the absence of predators hungry stickleback generally went for the centre of the swarm, but if a model kingfisher was flown over the tank they switched to the edge.
  • Stickleback optimise survival by trading foraging for vigilance when there are predators around
11
Q

simpson experiment

A
  • tested optimal diet using final instar catepillars

- compared protein eaten against carbs eaten

12
Q

cowie’s experiment conclusion

A

short travel time spent shorter time in patch

longer travel time spent longer time in patch

13
Q

central place foraging theory

A

animals collecting food and returning to a fixed point (central place) like a nest

14
Q

optimal prey choice e.g. shore crabs eating mussels

A
  • bell shaped curve

- choose mussels from the most profitable size class

15
Q

Elner and hughes experiment and conclusion

A
  • Each crab was offered equal numbers of mussels of each size class
  • measured the energy content of each size class, recorded how long it took crabs to open the shell and calculated profitability = (energy content)/(time to open shell).
  • they predicted the crabs would select mussels from the most profitable size class.