BIOL331 MODULE 4 ACTUAL EXAM
QUESTIONS AND CORRECT
ANSWERS LATEST UPDATE 2026/2027.
, 1. primary sexual characteristics✔✔ CORRECT ANSWER genitalia and organs of reproduction
2. secondary sexual characteristics✔✔ CORRECT ANSWER morphological ditterences between the sexes that are not directly involved in
reproduction
3. sexual selection✔✔ CORRECT ANSWER selection for traits that enhance mating success even if they have negative ettects on survival (benefits in mating
outweigh costs in survival)
4. intrasexual selection✔✔ CORRECT ANSWER mate competition; selection in which one sex competes with other members of the same sex for access to
the other sex for reproduction
-study✔✔ CORRECT ANSWER male dung beetles with large horns won more fights and mated with females; the maintenance of long horns can be explained by sexual
selection driven by male-male competition
5. intersexual selection✔✔ CORRECT ANSWER mate choice; selection by one sex ('choosier sex") for members of the other sex
for reproduction
-study✔✔ CORRECT ANSWER in peafowls, males (peacocks) performing the most displays and with the greatest number of ocelli obtained the most copulations; peacock
tails are used as an ornament in mate choice and females choose males with more ocelli
6. What hypotheses explain who should be "choosey" in a relationship?✔✔ CORRECT ANSWER (1)
Bateman's hypothesis
(2) Parental investment hypothesis
7. Bateman's hypothesis✔✔ CORRECT ANSWER the sex that has the highest reproductive limitation will choose the mate (typically females); male
reproductive success is limited by number of mates he has while the female reproductive success is mostly limited by the number and success of eggs that she can produce
8. parental investment hypothesis✔✔ CORRECT ANSWER the sex that has the greater investment of ottspring production
and care should be choosier when it comes to mates
9. What are three reasons why females notice/respond to displays?✔✔ CORRECT ANSWER (1)Sensory-bias hypothesis
(2) Direct material benefits
(3) Indirect benefits
10. sensory-bias hypothesis✔✔ CORRECT ANSWER females have a pre-existing bias toward noticing certain traits and are thus more likely to notice males
with those traits
-study✔✔ CORRECT ANSWER female guppies were attracted to the orange disc; female mating preference could be linked to preexisting preference for orange food objects
11. direct material benefits✔✔ CORRECT ANSWER material resources obtained by a female from mating with a particular male
(may get territories with abundant resources, nuptial gifts, and enhanced parental care)