Question

In a population of grasshoppers, some individuals are brown and others are green.

Presently, both phenotypes are equally fit. What could happen to change the relative fitness
of the two phenotypes in the population? For example, what could cause brown individuals
to show increased fitness relative to green individuals?

Answer 1

any external change in their environment that causes one phenotype to have an advantage over the other

Step-by-step explanation:

There are a few possible answers here. A good example might be if the grass they live in turns brown after a long drought, leaving the green grasshoppers more visible to predators than brown ones.