Evolution of Sociality

Question 1

Dilution Effect

Answer 1

Living in a group has the possibility of a predator eating someone other than you

Question 2

Cooperative Foraging

Answer 2

Bigger group can handle big/tough things with less cost to energy
-Work together to get more food and expend less energy

Question 3

Hamilton’s Rule

Answer 3

An altruistic allele increases when r x B > C
r; relatedness
B; benefit
C; cost

Question 4

Inclusive Fitness

Answer 4

An individual can get copies of her genes into the next generation either by producing more offspring herself or by helping her kin in their reproductive endeavors

Question 5

Eusociality

Answer 5

A single female or caste produces the offspring and nonreproductive individuals cooperate in caring for the young

Question 6

Game Theory

Answer 6

When social conditions determine behavioral strategies

Question 7

Evolutionary Stable Strategy

Answer 7

A behavior that, when adopted by most of the population, cannot be invaded by another strategy

Question 8

Reciprocity

Answer 8

Mechanisms whereby the evolution of cooperative or altruistic behavior may be favored by the probability of future mutual interactions.

Question 9

Group Selection

Answer 9

Differential fitness of groups causes some groups to outcompete others

Question 10

Individual Selection

Answer 10

Differential fitness of individuals causes some genotypes to outcompete others

Question 11

Hawk-Dove Conflict

Answer 11

V= Payoff
C= Cost of fighting
-Similar to Prisoner’s Dilemma (rewards and costs)

Question 12

Zone of Conflict

Answer 12

When priorities are mismatched between parents and their offspring
-Parents try to value all offspring equally but also need to value themselves and their energy

Question 13

Provide Costs and Benefits of Sociality

Answer 13

Benefits
-Dilution Effect
-Cooperative Foraging
Costs
-Parasite Load (living in close proximity, infections/parasites transfer a lot quicker)
-Decreased Reproduction Output (more competition for mates, especially in eusocial populations; ants and bees only have the queen mate)

Question 14

What leads to Cooperation?

Answer 14

1. Kin Selection
2. Reciprocity
3. Group Selection

Question 15

Provide characteristics of eusociality

Answer 15

1. Reproductive division of labor
2. Cooperative rearing of young
3. Overlapping generations

Question 16

Explain haplodiploid sex determination

Answer 16

All males are haploid and all females are diploid
-Because of the genetics of haplodiploidy, when a queen in a colony mates with a single male, sister workers are related to one another on average by a coefficient of relatedness r of 0.75; that is, the probability that a given parental allele ends up in both sisters is 0.75
-The probability that the sisters share a given allele copy through their mother is 0.25 (as in the case of diploid species), but because all males are haploid, the probability that sisters share an allele copy through their father is 0.5

Question 17

Explain Prisoner’s Dilemma

Answer 17

T= Temptation
R= Reward
P= Punishment
S= Sucker’s Payoff
-See where you have the most benefit, dealing high may have a bigger reward or a bigger consequence

Question 18

Provide Examples of Conflict among Kin

Answer 18

Offspring value contributions to self more than to siblings (offspring only care about themselves and about the parent feeding them but does not care about their siblings)

Question 19

Explain Honest versus Dishonest Signaling

Answer 19

-Honest signals are enforced by the community; community is more aggressive towards liars
-Honest signals tend to be more costly but are responded to

Question 20

Altruistic

Answer 20

An action that has the immediate consequence of reducing an individual’s own fitness while increasing the fitness of another