The process where a specie develops and evolves into new many species is termed as speciation. Macroevolution explores the mechanism of speciation where organisms across biological populations evolve as distinct population.
There are many causes to speciation, a) geographic isolation, b) gene flow reduction, and c) reproductive isolation.
Nerve cells because skin cells keep dividing when you loose skin. Epithelial cells also divide when you loose others.
Answer:
c.building immunity towards diseases
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It was the type of diversity that had to do with the niche depending on which niche you are is the amount of varaiaton in your gene pool