Question

over the years the vegetation in africa has grown taller and the giraffe population has also grown taller. Which type of selection is this?

Answer 1

This is an example of directional selection. Directional selection occurs when individuals at one end of the phenotypic range have higher fitness than individuals in the middle or at the other end of the range. In this case, the increase in vegetation height has provided a selective advantage to giraffes with longer necks, as they can reach leaves high up in the trees. As a result, the average height of the giraffe population has increased over time as individuals with shorter necks are less likely to survive and reproduce. This is an example of directional selection because the trait of interest (neck length) is shifting in one direction (towards longer necks) over time.

Step-by-step explanation:

Answer 2

What type of selection has occurred in this giraffe population?

Directional Selection

Example: Giraffes with the longest necks are able to reach more leaves to each. Selective pressures will work in the advantage of the longer neck giraffes and therefore the distribution of the trait within the population will shift towards the longer neck trait.