Question

onsider the following scenario: 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 the insect populations.

What is the main selective pressure in this scenario?

(1 point)
Responses

leg length
leg length

fish population
fish population

insect population
insect population

drought

Answer 1

The main selective pressure in this scenario is the **fish population**. The drought has caused the ponds to dry up, leading to a decline in fish populations, which directly affects the long-legged birds that rely on fish for food. The short-legged birds, which eat insects, are less affected since the insect population remains stable. Therefore, the competition for food due to the change in the availability of fish serves as the primary selective pressure impacting the bird population.