DIFFERENTIAL REPRODUCTION
In the simplest of terms, it means that within a population of any species, some individuals have better “traits” which aids them in their survival and they get to reproduce but at the same time there are other individuals of the population who will not be able to reproduce or even survive for that matter. There exists a differential state on who gets to survive and reproduce. Based on the theory of Natural selection, the ecosystem or environment cannot support all the Individual and only few of them survive and even among those not all get to reproduce.
REPRODUCTION ISOLATION
The mechanisms of reproductive isolation are a collection of evolutionary mechanisms, behaviors and physiological processes critical for speciation. They prevent members of different species from producing offspring, or ensure that any offspring are sterile.