In mammals, sexual selection is typically stronger in males than in females. Which explanation BEST reflects why males experience greater variance in reproductive success?
A. Males invest more in gametes, making offspring more costly to produce.
B. Female reproductive success is primarily limited by access to mates, not resources.
C. Male reproductive success is limited by the number of females they can mate with, not by gamete quantity.
D. Females benefit from male-male competition because it increases the overall survival of young.
C. Male reproductive success is limited by the number of females they can mate with, not by gamete quantity.
Which example below BEST shows the sensory bias hypothesis as described in sexual selection?
A. Female widowbirds prefer longer tails because they improve offspring survival.
B. Water mite females responding to male leg-trembling courtship because it mimics vibrations of prey.
C. Male seahorses providing paternal care to increase mate choice opportunities.
D. Female grey tree frogs choose longer calls because these males have superior genetics.
B. Water mite females responding to male leg-trembling courtship because it mimics vibrations of prey
What is the primary consequence when worker policing collapses in honeybee colonies?
A. Worker reproduction becomes more efficient, increasing colony survival.
B. Queens reproduce more frequently, restoring group stability.
C. Cheaters spread unchecked, leading to collapse of colony function.
D. Genetic diversity decreases, but colony performance stays stable.
C. Cheaters spread unchecked, leading to collapse of colony function.
Which evidence most strongly supports the Out-of-Africa replacement hypothesis over the multiregional hypothesis?
A. The Dali Man fossil dated to 260 kya.
B. Humans and chimpanzees share 99% DNA identity.
C. Mitochondrial Eve dating to ~200,000 years ago, indicating a single recent African origin.
D. Denisovans interbred with Melanesians 3-5% of the time.
C. Mitochondrial Eve dating to ~200,000 years ago, indicating a single recent African origin.
According to Hamilton’s Rule, which situation below would MOST likely allow altruism to evolve?
A. A sibling helps another sibling gain 3 extra offspring at a cost of 1 to themselves.
B. A cousin helps another cousin gain 2 extra offspring at a cost of 3 to themselves.
C. An individual helps an unrelated group member gain 10 extra offspring at a cost of 1.
D. An aunt helps a niece gain 1 extra offspring at a cost of 2.
A. A sibling helps another sibling gain 3 extra offspring at a cost of 1 to themselves.
When C. elegans is first exposed to a new pathogenic bacterium, the rate of sexual reproduction (outcrossing) increases. After the worms adapt and evolve resistance, the outcrossing rate decreases again. What is the best explanation for this pattern?
1) Sexual reproduction increases when conditions are stable and decreases when conditions become dangerous.
2) Sexual reproduction increases to help generate genetic diversity during stress, but decreases once adaptation is achieved.
3) Sexual reproduction always decreases over time regardless of environmental conditions.
4) Sexual reproduction changes randomly and is not affected by the environment.
2) Sexual reproduction increases to help generate genetic diversity during stress, but decreases once adaptation is achieved.
Why is it considered cheating when a worker honeybee lays her own egg?
1) Because the worker bee did not get permission from the queen bee
2) Because the worker bee did not get permission from the partner
3) Because it increases the total number of workers in the hive
4) Because the worker is using the colony’s resources for her own reproduction instead of helping the colony
4) Because the worker is using the colony’s resources for her own reproduction instead of helping the colony
Homo Sapiens emerged from:
a. Europe
b. Asia
c. Africa
d. The equator
c. Africa
Which of the following is NOT a method of preventing infanticide?
a. Young animals become aware of the threat and surge in size and weight.
b. Cause uncertainty of paternity by mating with multiple males.
c. Become extremely vigilant and aggressive toward threats.
d. Hide ovulation patterns.
a. Young animals become aware of the threat and surge in size and weight.
Which statement best explains why males typically experience stronger sexual selection than females?
A. Females produce more gametes than males, allowing greater variation in mating success.
B. Males have higher parental investment, limiting their reproductive rate.
C. Male reproductive success is primarily limited by access to mates, while females are limited by egg and pregnancy costs.
D. Females experience stronger competition because they must attract multiple males.
B. Males have higher parental investment, limiting their reproductive rate.
What determines whether an animal species will live in groups?
A. Whether individuals prefer cooperation over conflict
B. Whether benefits of group living outweigh costs at a given group size
C. Whether mating systems encourage monogamy
D. Whether group members are genetically related
B. Whether benefits of group living outweigh costs at a given group size
Why do some female mammals mate with multiple males during their fertile period?
A. To increase the chance of producing twins
B. To reduce infanticide by creating uncertain paternity
C. To gain access to extra food resources
D. To ensure only the strongest male sires’ offspring
B. To reduce infanticide by creating uncertain paternity
According to Hamilton’s Rule, altruism evolves when…
A. Cost to the actor is greater than benefit to the recipient
B. Benefit to the recipient is greater than cost, regardless of relatedness
C. rb > c, meaning benefit × relatedness exceeds cost
D. Actors can recognize cheaters and punish them
C. rb > c, meaning benefit × relatedness exceeds cost
Which of the following is a cost of group living?
A. Thermoregulation
B. Predator defense
C. Division of labor
D. Increased disease transmission
D. Increased disease transmission
Which hypothesis proposes that modern humans evolved in Africa and later dispersed to replace archaic hominids across the world?
A. Multiregional Hypothesis
B. Out-of-Africa (Replacement) Hypothesis
C. Parallel Evolution Hypothesis
D. Hominid Convergence Model
B. Out-of-Africa (Replacement) Hypothesis
In the social systems of most of mammal species, the mother’s investment into parental care is often larger than the father’s investment. What is one explanation for this asymmetry?
a) Mothers are better suited for parental care overall
b) Mothers are biologically predisposed to nurture their young, whereas fathers are biologically predisposed to hunt for food
c) Eggs and pregnancies are more expensive than sperm
d) Pregnancy caused mothers to be more emotionally and physically attached to their offspring, fighting off the fathers from being dominant in parental care
c) Eggs and pregnancies are more expensive than sperm
Some social contracts, e.g. female worker bees should not reproduce and lay their eggs in the colony, are beneficial towards the survival of the species. This is because the species wish to prevent cheating from spreading throughout the population Social contracts buffer against this cheating by …
a) Setting clear rules about expectations of behavior
b) Preventing group breakdown and reduce the costs of conflicts in the groups
c) Constantly threatening members of the species with retaliation, should they cheat
d) Assigning one head of police to monitor all cheating individuals
b) Preventing group breakdown and reduce the costs of conflicts in the groups
Which form of sexual selection is also known as “mate choice” or “female choice,” where males compete with each other to be chosen by females?
A. Kin selection
B. Natural selection
C. Intrasexual selection
D. Intersexual selection
D. Intersexual selection
Based on the phylogenetic relationships discussed, humans and chimpanzees are estimated to have diverged from a common ancestor approximately:
A. 1 - 2 mya
B. 6 - 8 mya+
C. 20 - 25 mya
D. 100 - 150 mya
B. 6 - 8 mya+
What is the cause of male preference, according to the null model of female choice?
A. Long-term environmental pressures
B. Random Genetic mutation with assortative mating
C. Learning from parental behavior
D. Differences in food resources.
B. Random Genetic mutation with assortative mating
Which of the following is the cost of group living?
A. Cooperative hunting
B. Thermoregulation
C. Disease
D. Predator defense
C. Disease
Why is altruism an evolutionary puzzle?
A. It cant be genetically inherited
B. It may reduce the fitness of the actor
C. Recipients benefit less than the actor
D. Will always reduce the group fitness
B. It may reduce the fitness of the actor
When did Neanderthal H sapiens divergence begin around?
A. 7 million years ago
B. 200,000 years ago
C. 55,000 years ago
D. 700,000 years ago
D. 700,000 years ago
Which of the following best describes the core idea of the Prisoner’s Dilemma?
a. Cooperation always gives the highest payoff to individuals
b. Defection gives a higher individual payoff even though cooperation gives a higher group payoff
c. Both players always benefit most from defecting
d. The best strategy is to switch randomly between cooperating and defecting
b. Defection gives a higher individual payoff even though cooperation gives a higher group payoff
