A.   The number of males who are available for mating

B.   The number of gametes females can produce

C.   Food availability

D.   All of these statements are correct

A.   Gaining more access to resources by being successful in competition with other females

B.   All of these statements are correct

C.   Gaining more access to resources by cooperating with other females

D.   Finding the optimal amount of care to invest in offspring

A.   The more females invest in the care of their offspring, the less time and resources they have to devote to future offspring

B.   Males invest more in care of offspring than females do

C.   Allomaternal care is more likely

A.   Both of these responses are correct

B.   favors traits that make individuals more attractive to the opposite sex

C.   favors traits that make individuals more successful in competition for access to mates

A.   How long a monogamous pair bond lasts

B.   Tail length

C.   Reproductive success

A.   False; males never invest in offspring

B.   In one-male/multi-female groups

C.   In species that have enduring pair bonds

A.   In multi-male/multi-female groups

B.   In one-male/multi-female groups

C.   In polyandrous groups

A.   Variation in reproductive success is the highest for males

B.   Humans are present

C.   Monogamy is common

A.   Ends when offspring are weaned

B.   Temporary

C.   All of these statements are correct

D.   Occurs because nursing requires an enormous amount of calories

A.   When a male increases in rank

B.   When a new female enters a group

C.   During the rainy season