Chapter 8

Question 1

Kinship

Answer 1

Relationship through common characteristics or common origin

Cooperation among relatives tend to be common leading to factor to social behavior

Question 2

Kin selection

Answer 2

The process by which traits are favored because of their beneficial effects on the survival of relatives

Enhance reproductive success of relatives

Question 3

Why is a trait favored?

Answer 3

Shared genes and behavior between kin can increase the future representation of ego’s genes

Question 4

Altruism or selflessness

Answer 4

Some animals behave in ways that reduce their individual fitness but increase the fitness of others

Question 5

Altruism

Answer 5

Personal sacrifice for the good of the group

Question 6

Inclusive fitness

Answer 6

The total effect an individual has on proliferating its genes by producing offspring and helping close relatives produce offspring

Question 7

Evolutionary definition of kinship

Answer 7

Probability that individuals share genes that they have inherited from common ancestor

Question 8

Relatedness

Answer 8

The probability that two individuals share genes that are identical by descent

Sibling relatedness=0.5

Question 9

Hamilton

Answer 9

Predicts when natural selection would favor altruistic acts among related individuals

(AΣ1rb)-c>0

Question 10

(AΣ1rb)-c>0

Answer 10

B=the benefit that others receive from the trait/gene (safety when heard the call)

C=the cost accrued to the individual expressing the trait (danger of being killed)

R=probability of relatedness (closeness among group)

A=how many individuals affected by the trait

Question 11

Three key variables in an altruistic act

Answer 11

Benefit to the recipient

Cost to the altruist

Coefficient of relatedness

Question 12

High relatedness

Answer 12

rXb is greater than c as b> and c< the probability of rb is greater than c increases

As A increases natural selection for the trait is more favored

Question 13

Brown’s offspring rule

Answer 13

Uses offspring as the currency of measure and provides a means to eliminate fitness and costs of assisting kin

Question 14

Reciprocal Altruism

Answer 14

Altruistic behavior toward unrelated individuals can be adaptive if the aided individual returns the favor in the future

Question 15

Steve Emlen’s theory of family

Answer 15

Kin selection- inclusive fitness

Ecological constraints theory- examines distribution of mature offspring

Reproductive skew theory- examines how reproduction is divided among potential breeders by predicting conditions that should favor conflict or cooperation over breeding decisions

Question 16

Parent offspring conflict

Answer 16

A zone of conflict between how much a given offspring wants in terms of parental resources and how much a parent is willing to give

Question 17

Weaning (Parent offspring conflict)

Answer 17

When mothers consider her life time reproduction success and reduce aid while each current brood also weigh its reproductive success (survival) more than the reproductive success of other sibling and beg for more aids

Question 18

Sex ratio in social insects (parent offspring conflict)

Answer 18

Male insects are haploid, while females are diploid. Sisters are more related and three times related to workers

Question 19

What happen if the queen dies and is replaced by one of her daughters?

Answer 19

Workers are equally related to the new queen’s sons and daughters and so they should favor a 1:1 sex ratio

Question 20

Parent induced infanticide (abortion/miscarriage)

Answer 20

Occurs when mother residual reproductive value is high and a resource is scare

Factors: age of female and resource

Question 21

Residual reproduction

Answer 21

When a female has more reproductive opportunities in her future

Question 22

Rule of thumb models

Answer 22

In species where kin groups are segregated from one another over relatively long periods of time, a second form of kin recognition may evolve