Which type of selection is illustrated by these two graphs?

Hello!

The type of selection which is illustrated by these two graphs is a Stabilizing Selection

Among the different types of Natural Selection. Stabilizing Selection is the one that happened to the parrot population in the rainforest in Costa Rica. This is characterized by the selection against the extremes of an attribute and reinforcement of the mean, that's why this type of selection is also called Selection towards the mean.

In this case, there was selection against the parrots with colored feathers other than green that didn't help them to camouflage in the rainforest. 

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