Question

A)
Consider the following scenario:
You are a scientist observing rodents on the Galapagos Islands. You notice that the
introduction of new bird of prey has limited the number of rodents.
What term best describes the factor that is limiting the number of rodents the
environment can support?
(1 point)
variation
fitness
selective pressure
food supply

Question 2
A)
Consider the following scenario:
In an aquatic bird population, some birds have long legs. Other birds have short
legs. The food supply is minimal. The birds with long legs are able to wade farther
into the water where they can find fish. Over time, the birds with long legs become
more common.
What scientific term best describes this scenario?
(1 point)
fitness
mutation
natural selection
selective pressures

Question 3
A) What relationship exists between changes in the environment and variations?
(1 point)
Changes in the environment can act only on existing variations in a population.
Changes in the environment cannot change which traits are advantageous.
Changes in the environment cannot influence the fitness of an organism.
Changes in the environment can only cause new variations to appear.

Question 4
A) Over time, the variation that gives an advantage (1 point)
becomes more common in the population.
can limit the number of selective pressures.
becomes less common in the population.
can limit the number of individual organisms.

Answer 1

Q1: selective pressure — the introduced predator is a selective pressure limiting rodents.

Q2: natural selection — long-legged birds have a heritable advantage and become more common.

Q3: Changes in the environment can act only on existing variations in a population. — selection acts on preexisting variation.

Q4: becomes more common in the population.