<span>The natural selection.
Natural selection is the differences in survival and reproduction as the consequence of differences in phenotypes.
In natural selection, genotype variations that will increase the chance of survival and reproduction of some organism are preserved and will be inherited. So genotypes variations are responsible for phenotypes and, thus, help the survival of species in a particular location.</span>
Females it begins prior to birth, while in males, it begins after birth.
<span>Why is carbon so abundant in living things when oxygen is the most abundant element on Earth?
</span>a. Carbon atoms can bond with one another to make chains and cyclic structures whereas oxygen atoms cannot form chains or cyclic structures.<span>
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