Black squirrels may increase in a certain area due to natural selection because of the ground below it being dark so the squirrels would adapt to the terrain, making them harder to see by predators.
EXAMPLE: if a light fur colored squirrel is on a dark terrain, an Owl or Large bird could easily see the color differentiation and notice that it is a small land organism (prey).
So the squirrels kin would evolve in the sense that they would have darker fur to match their inhabitance
Dna primase and Dna polymerase
The chemical is called Cholecystokinin,it helps<span> stimulates the gallbladder to contract and release stored bile into the intestine
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The answer is geographic distribution
