Ecology: Lecture 6 Flashcards
What might behavioural ecology observe?
Why particular behaviours persist in animal populations even if they seem counterintuitive, even if it seems like they should be eliminated by natural selection and evolution.
Looks at COSTS and BENEFITS
Through what lens do we look at behavioural ecology?
Through an evolutionary lens.
Who will pass on their genes?
Those with more appropriate behaviour will pass on more genes:
- More likely to survive
- More likely to produce offspring
- Those passing on genes might end up making the behaviour fixed in future populations.
What are behaviours composed of?
Innate behaviour and learned behaviour. If they are unfavourable, they will likely die and these behaviours will disappear.
How do we explain behaviour?
We explain behaviour in terms of effect on individual fitness.
What is “appropriate behaviour”
Appropriate in the context of the environment.
- Abiotic: climate
- Biotic: interactions within species and individuals.
High fitness vs. low fitness?
High = pass on genes
Low = poorly adapted environment and they are more likely to due before they’re able to pass on genes
What are benefits and costs in terms of fitness?
Benefit (high fitness) if fitness increases
Cost (low fitness) if fitness decreases
What is fitness (evolutionary)?
High fitness = more likely to survive
Low fitness = less likely to survive
Evolutionary fitness?
How likely an individual is to pass on its genes.
Actor?
The animal performing the behaviour
Recipient?
The other animals involved.
Altruism is ___?
Counterintuitive. It incurs a cost, and should be eliminated…?
Cooperative?
Actor = +
Recipient = +
Examples: defence and hunting
Selfish?
Actor = +
Recipient = -
Example: Territoriality
Spiteful?
Actor = -
Recipient = -
Example: surplus killing
Altruistic?
Actor = -
Recipient = +
Example: involves risk and harm, fitness would be lowered. eliminated?
Pika?
Related to rabbits
- live in rocky mountainous environments
- social groups with alarm calls made for predators.
Alarm calls do what?
Warns others - entire group of the predators
Increases risk to self - bringing attention to itself
Behaviour cost-benefit analysis?
Is benefit > cost?
Cooperative ( + + )
Selfish ( + - )
Altruistic ( - + ) NO!!
Inclusive fitness?
The total effect on number of genes passed on:
1. producing offspring
2. aid relatives to produce more offspring
What is inclusive fitness composed of?
there is more going on in passing genes than 1 individual and their offspring.
- Individual fitness + other evolutionary benefit of relatives passing on genetic material. Also passes on own behaviour.
Kin selection?
Selection for an act that enhances a relative’s reproductive success.
- Some genetic material is shared with relatives
- Genes are passed on not just through offspring but also through relative’s offspring.
Hamilton’s Rule?
Natural selection (evolution) favours an act if:
C < r x B
C = cost to altruist (lost reproduction)
r = relatedness (fraction of shared genes)
B = benefit to recipient (increased reproduction)