Evolution of Social Behaviour

Question 1

What is grooming?

Answer 1

An altruistic act; benefits the recipient (hygiene, relaxation), costly for the giver (time consumed away from other important tasks)

Question 2

What are some examples of altruism?

Answer 2

• Alarm calling
• Coalitions in conflicts
• Food sharing
• Alloparenting (parenting other infants)

Question 3

What are the different interactions?

Answer 3

• Selfish: benefits the actor and costly to recipient
• Altruistic: benefits recipient and costly to recipient
• Mutualistic: beneficial for both
• Spiteful: costly for both

Question 4

Is group selection a thing?

Answer 4

No, it cannot explain evolution of altruistic behaviours

Question 5

What is the answer to altruistic behaviours?

Answer 5

Kin selection (relatedness influence altruistic acts)

Question 6

What is kin selection?

Answer 6

When individuals interact selectively with relatives (callers more likely to benefit than non-callers)

Question 7

When is calling favoured?

Answer 7

When the benefits are sufficiently greater than the costs

Question 8

When will an altruistic act be favoured by selection?

Answer 8

When the following inequality is satisfied: rb > c
b = sum of fitness benefits to all recipients
r = relatedness
c = cost to the giver

Question 9

What are the 2 important predictions of hamiltons rule?

Answer 9

• Altruism should be directed towards kin (r = 0 for unrelatedness)
• Closer genetic relatedness allows for more costly altruism (benefits must be twice as great)

Question 10

How do primates recognize kin?

Answer 10

• Phenotypic matching (smell or likeness to self)
• Contextual clues (familiarity, proximity, observe patterns of association)

Question 11

Discuss kin recognition.

Answer 11

• Easier to recognize maternal kin using contextual clues (can identify your siblings as who else your mom spends a lot of time with)
• Paternal kin are harder to identify, age may provide clues in polygynous species

Question 12

Discuss coalitions.

Answer 12

• Coalitions last longer and are more intense when males are related (take over group, defend territory)
• Cooperative breeding (polyandry)

Question 13

When does parent-offspring conflict occur?

Answer 13

• Fitness of future offspring comes at expense at current offspring
• Mother wants to invest more in future offspring
• Current offspring want mother to continue to invest in them

Question 14

What is reciprocal altruism?

Answer 14

Altruism can evolve among non-kin if they take turns giving and receiving (reciprocity drives this type of altruism)

Question 15

What are the requirements for reciprocal altruism?

Answer 15

• Must have opportunities to interact often
• Must be able to keep track of support given and received
• Must provide support only to those who help