Lecture 5- Foraging (what to eat)- Introduction to Optimality theory. Flashcards
What can you say about this area of animal behaviour?
Why do people conduct an optimality analysis?
Easy to quantify benefits and costs- can just weigh things like food.
To see if animals are behaving in an optimal way.
What is foraging?
What do you use to understand foraging decisions?
When animals are looking for food and deciding what to eat.
The optimality theory.
What are humans?
What kind of humans exist however?
What do humans have a choice about?
What do animals not do?
What do they use?
Generalist- willing to eat a range of things.
Selective- limited diets- like only eating crisps for years.
What to eat.
Make conscious, deliberate decisions like humans when choosing what to eat.
Rule of thumb.
Decision-making adaptations:
What should animals have evolved?
Where?
What does it lead them to do?
What does behaving in this way maximize?
What can be considered a cost?
Decision making adaptations
In their brains.
Make optimal choices when choosing food.
Fitness benefits in comparison to costs.
Time spent looking for food- could have spent this time looking for mates.
Continuation from decision-making adaptations:
What are animals expected to be?
Maximally efficient- in things that lead to fitness- like attracting mates + obtaining food.
Continuation from decision-making adaptations:
What are adaptations?
How have these adaptations spread?
Mechanism- in their nervous system- leads them to make decisions.
Through natural + sexual selection.
Continuation from decision-making adaptations:
What have they replaced?
What does it have be in terms of the fitness-benefits versus fitness-cost ratio?
What does a trait not need to be?
Alternative traits in species- adaptations led them to do beneficial stuff.
Alternative forms which occurred in the past.
Perfect- to evolve- just needs to do better than alternative strategies.
Optimality analysis:
What do this include?
What is easy to quantify?
What do animals try to do in terms of food?
How can this be quantified?
Quantifying the benefits and costs of what an animal is doing.
Benefits of food items.
Try to get as much energy as they can.
In things like calories or micronutrients.
Continuation from the optimality analysis:
What do costs include?
What else does it include?
What needs to be made?
Explain.
The energy needed to get, handle and digest the food.
Risk associated with finding food (like getting seen and eaten).
Trade-offs.
Are benefits + risks to getting nutritious food- needs to be balanced against each other.
What is an optimal strategy?
What determines whether a strategy is optimal?
One that gives best ratio of benefits to costs.
Balance between costs and benefits.
Assumptions behind optimality:
What is the first assumption?
What is it?
What happens if the environment is changing a lot?
Stationary environment.
Idea that- current environment- similar to one animal evolved in- animals today are facing similar problems to ones in past.
What animals are doing might not be optimal anymore.
Continuation from assumptions behind optimality:
What is the second assumption?
What is heritable?
If it is an adaptation, what has it got to be?
Inheritance.
The behavioural mechanism (trait).
Heritable.
Continuation from assumptions behind optimality:
What is the third assumption?
What is it?
What had the greatest fitness benefit for animals?
Variation.
Genetic variation in population- selection picked best variant- alternative strategies tried- best evolved, others got lost.
The trait that worked well.
Continuation from assumptions behind optimality:
What is the last assumption?
What is this?
What does selection lead to?
Differential fitness.
Inherited behavioural trait affects fitness.
Population being dominated by individuals that make good decisions (have high fitness)- those that made bad decisions, did not survive so left no offspring.
Optimality analysis:
What is step 1?
Explain.
What do you need to do first?
What happens after this?
Give an example of a decision an animal (black bird) might need to make.
Identify the problem.
What decision is the organism trying to make?
Need to identify problem before asking what solution the organism should adopt.
Test to see if animals are adopting the best solution.
Should I eat the beetle or worm.
