What are some benefits of living in groups?
- increase chances of survival
- increase their rate of feeding
- increase success in finding mates
What are some costs of living in groups?
- predation
- competition
What is a territory?
An area defended by one or more individuals to protect against the intrusion of other individuals.
What are the 4 types of social interactions?
- cooperation
- selfishness
- altruism
- spitefulness
Give an example of cooperation.
2 animals helping each other hunt and splitting the food afterwards.
Give an example of selfishness.
Baby birds hogging food.
Give an example of spitefulness.
No natural examples.
Give an example of altruism.
When a mother octopus dies after caring for her clutch of eggs.
Worker bees/ants forgoing reproduction to serve their queen
Why is it difficult to explain the evolutionary benefits of altruism?
It decreases an individuals fitness in favour of increasing a different individuals fitness. This means the donor of the behaviour is favouring a different individual's chances of reproducing over their own.
Compare direct and indirect fitness.
- Directly vs indirectly passing your genes to offspring by yourself procreating vs helping a relative procreate
What is the coefficient of relatedness? Why does it explain why
altruism towards a non-relative provides
no indirect fitness
benefit to the donor.
The probability that copies of a particular gene are shared by relatives. The donor and non-relative share no genetic material so the offspring of the recipient is not furthering any of the donor's DNA.
How does haploid sex determination work?
One sex is created by being haploid while the other is created by being diploid.
Why does haplodiploid sex determination favour eusociality?
The fitness benefit of taking care of an sibling of the same sex is greater than that of raising a child of the same sex.
What conditions would lead to an individual of a diploid species helping raise the offspring of its siblings rather than reproducing itself?
Conditions where the cost of forgoing personal reproduction is small. For example if the rate of success for starting a new colony (in a species of colonial animals) is low.