Lecture 6 Flashcards
(28 cards)
Behavioural ecology
Focuses on individual behaviours and how they influence fitness and the interactions with the environment.
Which to aspects of behavioural ecology are we going to see
- Foraging Behaviour
- Sexual Selection
Example of foraging behaviour
Organisms need to make this decisions because they need energy on a limited time
Optimal foraging theory is based on the idea that
Natural selection will influence how organisms feed and behave while foraging.
Optimal foraging theory assumes that
Natural selection is likely to favour individuals within a population that are more effective at acquiring limited resources.
How are the optimal foraging models?
They maximize the net energy gained per unit feeding time
Which to models are we going to study?
- Charnov’s Marginal Value Theorem (patch model)
- Optimal Diet Composition Model
What’s the question for Charnov’s Patch Model?
How long should an organism stay feeding in a given patch? Charnov’s patch model – Marginal Value Theorem
When taking longer to travel to a patch, will an individual spend more or less time in the patch?
More
If patch quality is decreased, will an individual spend more or less time in a patch?
Less
Which ones are the predictions from the Model?
- Foragers should abandon a patch when the rate of energy gain is at a maximum.
- Foragers should stay in a rich patch longer than in a poor patch.
- For patches of the same quality, time spent foraging should increase with time spent travelling to a patch.
What is food abundance in foraging?
The quantity of different food types available, which varies in time and space.
What is handling time in foraging?
The time it takes to handle and consume a food item.
How do organisms maximize their rate of energy intake?
By choosing foods that provide the most energy relative to handling time and availability.
What’s T in optical diet model?
Forager Time
What’s Ts in optical diet model?
Searching time
What’s Th in optical diet model?
Handling time
What’s Pi in optical diet model?
Prey items
What’s Ei in optical diet model?
Energy value gain by eating
How is profitability measured?
Ei (energy gain by eating)/ Thi (handling time)
Which ones are your choices if you are foraging and you encounter a less profitable item?
- Eat a less profitable item
- Go search for the most profitable item
Which one is the formula if you eat a less profitable item?
𝐸2/ 𝑇ℎ2
Which one is the formula if yougo search for the most profitable item?
𝐸1/(𝑇ℎ1 + 𝑇𝑠1)
What determines whether an organism is a specialist or a generalist?
The decision to include less profitable food items depends on the search time for the most profitable prey
