Question

2. The Isthmus of Panama cut off gene flow between Atlantic and Pacific populations of a species of fish. The cessation of gene flow led to the accumulation of genetic differences between the populations, which led to reproductive isolation. Now Atlantic and Pacific populations of this fish are separate species that cannot interbreed, even if they were again to come into contact with each other. The process described is that of
a. sympatric speciation.

b. parapatric speciation.

c. allopatric speciation.

d. reinforcement.

e. temporal isolation.

Answer 1

Answer:

C Allopatric Speciation

Explanation:

Evolution of two populations of same species into two separate species due to geographical isolation is called allopatric speciation.  

In the given example, Isthmus of Panama serves as a geographical barrier and do not allow the interbreeding between Atlantic and Pacific fish populations of the same species.  

These populations evolve genetic adaptation to make themselves better suited to the prevailing surroundings. Accumulation of genetic variations over generation leads to their reproductive isolation. Now, these two fish populations serve as two separate species as they can not interbreed.