Natural Selection and Adaptation Quiz

A drought hits the habitat of a semi-aquatic bird population. All ponds dry up, and fish populations decline. There are two groups of birds in the population that differ in leg length and diet. Long-legged birds eat fish, while short-legged birds eat insects. The drought has little effect on insect populations. What is the main selective pressure in this scenario?

• Insect population

• Fish population

• Drought

• Leg length

Which statement is accurate about variations?

• Organisms with variations are less likely to pass these variations to their offspring.

• In all cases, variations affect how likely it is that an organism reproduces.

• In all cases, variations become more common in a population.

• Organisms with variations that give an advantage are more likely to survive.

In a muddy lake environment, some fish have brown scales. Most fish, however, have silver scales. Predators have a harder time seeing the fish with brown scales. Which term best describes the brown scales?

• Advantageous trait

• New mutation

• Predominant phenotype

• Inactivated gene

How did the Industrial Revolution impact the population of peppered moths in Britain?

• The dark-colored moths became more common.

• The Industrial Revolution caused the proportions of each color morph in the population to become unequal.

• The light-colored moths became more common.

• The Industrial Revolution caused the proportions of each color morph in the population to become equal.

There are two varieties in a population of squirrels: short tails and long tails. Long-tailed squirrels are better at jumping and balancing in trees. Scientists observe that over the span of 100 years, the proportion of the population with long tails increases from 10% to 60%.

• Natural selection favors long tails.

• Long tails are a disadvantage.

• Short tails are becoming more common.

• The environment favors short tails.

Which statement is most likely?

• The proportion of short-tailed squirrels may have decreased due to an increase in trees.

• The proportion of short-tailed squirrels may have decreased due to decreased food availability.

• The proportion of long-tailed squirrels may have increased due to a decrease in trees.

• The proportion of long-tailed squirrels may have increased due to increased food availability.

Why is the cheetah gene pool small today?

• Lack of advantageous traits

• Poor adaptability

• Multiple bottleneck events

• Inbreeding in zoos

After a bottleneck event, the population of rabbits in an area has significantly decreased. A decade later, the population of the rabbits recovers to its original numbers. Which statement is correct about the rabbits?

• They are less likely to survive environmental changes because of the bottleneck event.

• They are as likely to survive environmental changes because their population has recovered.

• They are as likely to survive environmental changes because they survived the bottleneck event.

• They are more likely to survive environmental changes because of the bottleneck event.

Facts or data are types of:

• Models

• Reasoning

• Evidence

• Explanations

What change is observed in a distribution curve for a trait affected by directional selection?

• It shifts either to the right or the left.

• It shifts to the right and to the left.

• It shifts to the left.

• It shifts to the right.