Question

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. A new mutation would emerge that introduced a gray color to the anole population.
• B. The numbers of brown versus green anoles in the population would shift to a more balanced ratio over time.
• C. The number of green anoles in the population would increase further.
• D. The anole population would go extinct.

Answer 1

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

These can have additive effects with animals being more likely to respond if a threat than a predator that is approaching and looking directly at its prey Anolis lizards (Anolis sagrei) become more arboreal following the introduction of a walking stick insects mimic the motion of plants in the wind to avoid detection.

So, the answer is 'The numbers of brown versus green anoles in the population would shift to a more balanced ratio over time'