Question 1

Secondary sex ratios refer to:

Accepted Answer

Secondary sex ratios refer to the sex ratios at birth, meaning the ratio of male to female offspring produced by a particular population.

Question 2

Which of the following statements about development is true

Accepted Answer

The energetics of maternal body size can influence the growth rates of infants, as larger maternal body size often correlates with greater energy reserves and resources available for offspring growth.

Question 3

Greater prenatal maternal investment leads to:

Accepted Answer

Heavier infants relative to maternal weight in haplorhines is the correct answer because haplorhines have a longer gestation period and provide more nutrients to their offspring during pregnancy, which results in larger infants relative to maternal weight.

Question 4

Prolactin is a hormone:

Accepted Answer

Prolactin is associated with parental care in both males and females. It is involved in the regulation of maternal behavior in females and paternal behavior in males, such as nest-building and pup-retrieval.

Question 5

In many social primates, primiparous mothers differ from multiparous mothers in:

Accepted Answer

Primiparous mothers have higher rates of infant mortality compared to multiparous mothers. This is due to their lack of experience in maternal caregiving and handling newborns, which results in higher rates of accidental harm or neglect. The other options (A, C, and D) are not necessarily true across all social primates and are not specifically linked to primiparous vs. multiparous mothers.

Question 6

Baboon mothers with a relaxed, "laissez-faire" mothering style tend to be:

Accepted Answer

Research studies have found that baboon mothers with a relaxed, "laissez-faire" mothering style tend to be high ranking in their social groups. This is likely because they have built a strong social network and have the support of other individuals in the group, making them more relaxed and less stressed when it comes to their infant care.

Question 7

The evolutionary explanation for the weaning conflict is based on:

Accepted Answer

The weaning conflict occurs when a parent and offspring have divergent interests as to when nursing should cease. According to evolutionary theory, this conflict arises because the offspring's fitness is maximized at a later age than the parent's fitness. As a result, the parent is motivated to invest less in the offspring than the offspring desires. This conflict leads to weaning, which is typically initiated by the parent.

Question 8

Juvenile primates:

Accepted Answer

Juvenile primates grow slowly to reduce competition with adults for resources, allowing them to develop skills and social bonds necessary for survival.

Question 9

Sex differences are evident:

Accepted Answer

Sex differences in maturation rates are a common phenomenon in sexually dimorphic species, where males often mature later than females. This is observed across various species, including humans, and is a result of evolutionary and biological factors.

Question 10

In nearly all primates:

Accepted Answer

In nearly all primates, mortality rates among sexually mature males exceed those of females. This is often due to factors such as competition among males for access to females, riskier behaviors, and higher levels of aggression, which can lead to increased mortality rates.

Question 11

The composition of juvenile play groups often reflects:

Accepted Answer

The composition of juvenile play groups often reflects whether they rely more heavily on adults or peers for social support. Juvenile animals that rely more on peer socialization often form play groups with individuals around the same age and developmental stage, while those that rely more on adult socialization may play more frequently with adult members of their group. The other options (B, C, and D) are not necessarily related to the composition of juvenile play groups.

Question 12

Which of the following statements about the behavior of these juvenile primates is false?

Accepted Answer

Male rhesus and Japanese macaques typically leave their natal groups upon reaching maturity and are not well integrated into adult male networks in their natal groups from a young age.

Question 13

The population consequences of high mortality among dispersing primates:

Accepted Answer

High mortality among dispersing females can lead to reduced gene flow and population connectivity, potentially impacting population viability more severely than when males, who typically disperse, experience high mortality.

Question 14

High levels of prenatal androgens:

Accepted Answer

High levels of prenatal androgens lead to masculinized fetuses, as androgens are male sex hormones that promote male characteristics such as a deeper voice and increased muscle mass.

Question 15

The heterogametic sex:

Accepted Answer

The heterogametic sex, which is typically the male in mammals and birds, determines whether a zygote will be male or female based on whether it contributes an X or Y chromosome.

Question 16

According to Janson and van Schaik, juvenile primates adopt a "risk averse policy" in order to:

Accepted Answer

Juvenile primates adopt a "risk averse policy" in order to stay alive until they are capable of competing with adults. This allows them to survive long enough to develop the skills and strength necessary for adult competition.

Question 17

Discuss the costs and benefits of allomothering behavior, and describe the conditions under which the frequency of allomaternal behavior varies across different primates.

Accepted Answer

The answer of Discuss the costs and benefits of allomothering...

Question 18

Discuss two explanations for why male primates differ in the degree to which they participate in parental care.

Accepted Answer

The answer of Discuss two explanations for why male primates...

Question 19

List three differences that distinguish precocial (P) and altricial (A) infants, being sure to indicate if you are describing (P) or (A) characteristics.

Accepted Answer

The answer of List three differences that distinguish precocial (P)...

Question 20

Draw the graph depicting parent-offspring conflict. Label both the X-axis and the Y-axis, all curves, and where PI is optimized from the parent's and offspring's perspective. Indicate the area of conflict and briefly explain the basis of the conflict.

Accepted Answer

The answer of Draw the graph depicting parent-offspring conflict. Label...

Quiz 9: Developmental Stages Through the Life Span