Question

What exactly is differentiation in genetics? Detailed and as simple as possible please

Answer 1

If there are two or more population living in an ecosystem, but due to some barrier gene flow has been restricted to some extent, then after a decade the genetic combination or characters in those population will be different from each other. As there is restriction in the gene flow between populations, the genetic combinations will be different and hence results in genetic differentiation. The barrier may be ecological or geographical. As the freshwater organisms live in ponds, lakes etc, hence these lakes and ponds don't allow the flow of genes from one population living in it to another population living in another lake or pond and hence results in differentiation in genetics.