Question

While all giraffes are tall they are not all the exact same height. Within a population, the height of each individual giraffe can vary. Scientists observe that over many generations the average height of the giraffe population is increasing. They believe this in response to trees producing fewer leaves on lower branches, meaning the giraffes' main food source is higher up.

What kind of selection is this an example of?

(1 point)
Responses

Disruptive Selection
Disruptive Selection

Directional Selection
Directional Selection

Stabilizing Selection
Stabilizing Selection

Directional Selection and Disruptive Selection

Answer 1

This is an example of **Directional Selection**. In this case, the average height of the giraffe population is increasing over generations because taller giraffes have an advantage in accessing food that is higher up in trees. This leads to a shift in the population toward greater height.