Social Behaviour - 22

Question 1

Define eusociality

Answer 1

an extreme form of reproductive altruism

Question 2

What 3 traits are required in order to be eusocial

Answer 2

1. cooperative care of young
2. reproductive division of labour
3. over-lapping generations

Question 3

Why does haplodiploidy predispose eusociality

Answer 3

because individuals are more related in haplodiploidy than diploid:
0.5 female to mother (same in diploid)
0.75 female to sister!!! (0.5 in diploid)
0.25 female to brother (0.5 in diploid)
females benefit more through inclusive fitness than reproduction (more related to sisters than own offspring)

Question 4

Why is it not a simple relationship between eusocial and haplodiploid individuals

Answer 4

1./2. because haplodiploid is based off of single queen and single sire
3. phylogeny doesn’t always support this meaning not all individuals that are haplodiploid and are eusocial and vise versa

Question 5

What trait coincides with the evolution of eusocial behaviour

Answer 5

nest-building behaviour

Question 6

What could be an explanation for the social structure of naked mole rats being produced and maintained

Answer 6

through the intimidation imposed by the queens
they have domination and if any individuals are slacking (specifically those less closely related) get headbutt as an effective tool
even though not haplodiploid individuals!

Question 7

What kind of conflicts can arise from social behaviours

Answer 7

1. parent-sibling conflict
2. sex-ratio conflict

Question 8

Explain parent-offspring conflict

Answer 8

parents want to benefit reproduction of their current offspring as well as increase reproduction in the future whereas offspring want to only increase their own reproductive fitness

Question 9

Explain the weaning conflict specifically in terms of parent-offspring conflict

Answer 9

the conflict is that offspring do not want to wean early because they want as much parental care to make it easier while parents want to wean to be able to reproduce more offspring and increase their fitness

Question 10

What is siblicide and what kind of conflict is it

Answer 10

siblings kill each other
parent-offspring conflict

Question 11

Define facultative vs. obligate siblicide

Answer 11

facultative = smaller siblings are killed ONLY WHEN resources are low (extra reproductive value)
obligate = smaller siblings are always killed regardless of resource availability (insurance reproductive value)

Question 12

Define reciprocal altruism

Answer 12

altruistic behaviour that will be reciprocated in the future between non-kin

Question 13

what are the 2 factors for selection to result in reciprocal altruism

Answer 13

1. cost to donor<benefit to recipient
2. recipients that don’t reciprocate are punished (no cheating)

Question 14

What are the 4 factors that make reciprocal altruism likely evolve

Answer 14

1. stable groups (recipients are known to donors) (familiar to each other)
2. there are multiple opportunities for altruism (interactions)
3. individuals remember the donor’s behaviour
4. altruism is bidirectional (reciprocal)