Amutation of a brown exoskeleton has been introduced into the green beetle population above explain what might happen to the population with the introduction of this new trait

A mutation in the population of green beetle caused the creation of the new trait (brown color), that would make the genes for brown beetles become more frequent in the population. That created difference introduced by mutations might be advantageous and may help an organism survive. For example, green beetles are easier for predators to see and consequently eat than brown beetles. Thus, brown beetles are a little more likely to survive to produce offspring.  

This is an example of how one evolutionary mechanism (mutation) can cause evolutionary change.

every el niño cycle is different. every year.

it takes hundreds of years to become stable.

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