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Evolution of Populations


A study on the rate of evolutionary change in the anole lizard populations of a group of islands over a 12 year period determined that the average coloration pattern in a certain population changed from predominantly brown with green flecks to predominantly green with brown flecks.

This occurred during a prolonged pattern of above average annual rainfall between 1971 and 1983. During that time, there was an increase in the number broad-leaved, green plants.

What effect might the introduction of a predator that hunts anoles using motion rather than color to detect its prey have on the coloration patterns in the anole population?


A new mutation would emerge that introduced a gray color to the anole population.


The numbers of brown versus green anoles in the population would shift to a more balanced ratio over time.


The number of green anoles in the population would increase further.


The anole population would go extinct.