Kin Selection

Question 1

What is altruism?

Answer 1

An altruistic behavior is one that increases the fitness of another individual (the recipient) at the expense of the altruist (actor)

Question 2

Direct fitness is given to what kind of kin? How about indirect fitness?

Answer 2

Direct -> Descendant kin
Indirect -> Collateral Kin

Question 3

Inclusive fitness

Answer 3

The combination of direct and indirect fitness

Question 4

How do you calculate relatedness?

Answer 4

(Prob. it’s from mom) * (if from mom, prob. sibs share) + (prob. it’s from dad) * (if from dad, prob sibs share)

Question 5

Hamilton’s rule

Answer 5

(r*b) - c > 0
b = benefit to recipient
c = cost to actor
r = relatedness
If greater than 0, then yes help

Question 6

What sort of predictions might we infer from kin selection?

Answer 6

Individuals should help relatives rather than non-kin and individuals should help close relatives more than distant relatives

Question 7

Which formula for Hamilton’s rule works every time?

Answer 7

(rb)*b - (rs)c > 0
rb = relatedness to recipient’s offspring
rs = relatedness to own offspring

Question 8

Altruism should be more frequent in what kind of groups?

Answer 8

Parent-offspring groups, rather than in groups of siblings

Question 9

What is Hamilton’s rule for multiple recipients?

Answer 9

(r1)b1 + (r2)b2 + (r3)b3 - rsc > 0

Question 10

How do you know who your kin are?

Answer 10

Perception: Perceive and compare recipient to template
Production: Some cues (scent)
Action: Make a decision, and act

Question 11

What are the mechanisms of kin recognition?

Answer 11

Spatial location, associational, phenotype matching, green beard alleles

Question 12

What is spatial location?

Answer 12

Template learned from cues associated with locations not individuals phenotypes

Question 13

What is the associational mechanism of kin recognition?

Answer 13

Recognition only of familiar individuals (e.g. specific cues of individuals present in learning period)

Question 14

What is the phenotype matching mechanism of kin recognition?

Answer 14

Actor learns generalized cues of some reference, then later matches template to recipients cues (permits recognition of unfamiliar kin)

Question 15

What is the green beard allele mechanism of kin recognition?

Answer 15

Production, perception, and action components all encoded by a single gene or tightly linked genes (an unlearned template)
Ex: green beard in red fire ants. BB alleles are executed by Bb workers. It is a transferrable odor cue

Question 16

Kin selection

Answer 16

A type of natural selection where individuals will sacrifice their own lives in an effort to save closely related organisms, ensuring the survival of genes that they both share.