Question

Examine the following scenario: A population of small fish lives in a lake (Lake A).The dark-colored fish are the ancestral phenotype and represent the usual coloration of the species. The bright-colored fish, however, arose over time. There is a steady rise in the population of bright-colored fish. Both populations thrive. Suppose that a short land barrier separates Lake A from another small lake with a population of only the normal dark-colored fish (Lake B). After torrential rains lasting for days, the lakes overflow and a few of the bright-colored fish from Lake A are washed into Lake B. List the sequence of evolutionary mechanisms which have come into effect in each event.

Answer 1

ANSWER:
Dark coloured fish living in lake B while bright colored fish living in lake A, each group of fush have same gene fool where random mating is possible and chances of speciation is null. However, when migration of one group of fish occur toward another group of fish then gene flow also occured. This result into breeding amongst members of two different groups. So the chances for speciation increase, and it is possible that with the passage of time new species may develop.