Lecture 7

Question 1

what are the Benefits of group life:

Answer 1

Direct access to mates
increased acquisition and control of resources
protection from predation through the “three D’s:” detection, deterrence and dilution

Question 2

what is detection

Answer 2

(can detect the predators)

Question 3

what is deterrence

Answer 3

(detters any attack from predators)

Question 4

what is dilution

Answer 4

(diluting the effect, reducing the effect, that a predator can have on a group… the bigger the group the less an attack will impact them)

Question 5

what are the Drawbacks to group life

Answer 5

increased likelihood of disease transmission

dramatically increased competition for resources and mating partners

Question 6

what are the Types of Primate Social Organization

Answer 6

solitary
females and offspring form tight groups and the males are left no the outside
pair-‐bonded (monogamous)
one female, many males (polyandry)
one male, many females (one-male polygyny)
many dominant males, many females (multi-male polygyny

Question 7

How does sexual reproduction and sexual selection factor into the social lives of primates in within these groups?

Answer 7

Understanding sexual reproduction and care for offspring within primate societies can shed light on the evolution of human social development

Question 8

Why wouldn’t males always be more involved in child-rearing?

Answer 8

The benefits of child-‐rearing must be weighed against the benefits of continuing to mate with available females.
Cost vs. benefit

Question 9

Absent fathers are selected for when two conditions are met:

Answer 9

1. there is widespread availability of, and access to, additional females
2. females within the group are generally able to raise offspring as well as when both parents are present

Question 10

Why are females the only sole caregivers?

Answer 10

1. The investment of time and energy related to pregnancy

2. The ability to lactate

Question 11

Primate gestation periods are, compared with those of most mammals, relatively long, from between 59 days to 9 months
This is due primarily to:

Answer 11

1) size of the mother

2) brain development of the infant

Question 12

do Most primate young remain dependent for longer periods

Answer 12

Most primate young remain dependent for longer periods than do the young of most mammals

Question 13

what is lactational amenorrhea

Answer 13

reducing or eliminating their fertility from between one to three years

Question 14

do female primates experience lactational amenorrhea

Answer 14

yes

Question 15

Why are long pregnancies, long periods of infant dependency and lack of fertility while nursing selected for?

Answer 15

1. Primate young require additional attention

2. Most nonhuman primates can continue reproducing very late in life

Question 16

Phenotypic differences between males and females within a species are characterized as what

Answer 16

sexual dimorphism

Question 17

what is sexual dimorphism

Answer 17

an adaptive response to competition between males for access to females.

Question 18

The degree of difference between males and females relates directly to what

Answer 18

the type of social organization present

Question 19

Sexual dimorphism is most exaggerated within what kind of group

Answer 19

one-male polygynous primate groups.
This is due to regular challenges to the resident dominant male by itinerant “bachelors
these groups are forming and then try and break in and overthrow the alpha male

Question 20

Among solitary primates, the degree of sexual dimorphism is;

Answer 20

high

Question 21

degree of sexual dimorphism is low where

Answer 21

it is low among polyandrous New World monkeys;

Question 22

what is sexual dimorphism like within groups comprised of multiple males and multiple females

Answer 22

it varies a lot

why? there is no competition, the animals do not care who has the offspring, as long as everyone pitches in and help to raise them when they come

Question 23

Pair-‐bonded species, such as gibbons, have the ______ degree of sexual dimorphism among primates.

Answer 23

lowest

Question 24

what is the degree of human sexual dimorphism like

Answer 24

The degree of human sexual dimorphism is relatively low; among primates, it lies between that of pair-bonded and polygynous species.
This indicates that some degree of regular competition for mates has played a significant role in human social development.

Question 25

what is Infanticide

Answer 25

is the purposeful killing of infants within a group

Question 26

infanticide is often part of the transition of dominance within a group; new dominant males will kill infants to;

Answer 26

1) free mothers for procreation

2) ensure that all infants within the group are his

Question 27

Dominant females in _______ groups will sometimes commit infanticide for similar reasons

Answer 27

polyandrous

Question 28

Dominant females in polyandrous groups will sometimes commit infanticide for similar reasons, why is this

Answer 28

they want to ensure the they know who the father is so they can get investment…

Question 29

The complex social relationships that typify primate social organization are closely related to what

Answer 29

cognition

Question 30

Natural selection favors the ability to what from peers

Answer 30

Natural selection favors the ability to both innovate and learn innovative techniques from peers