Question

The inability of two populations to interbreed after long separation is known as-
A. Succession
B. Dispersion
C. Fertilization
D. Speciation
E. Mutation

Answer 1

The number of individuals living in an area, district, city, or country is termed as population. In biological terms, population is defined as the number of the same species as living in a specific geographical area and which are capable of interbreed among themselves.

Complete answer:
The process of changing the structure of species which are living in an ecological community for some time, and forms a climax community is called succession. The species involved in this are able to interbreed afterwards. Thus, the option [A] is incorrect.

The scattering or dissemination of organisms in a given area, within a particular time is called dispersion. The species involved in this are able to interbreed afterwards. Thus, the option [B] is incorrect.

The process by which a male and female gamete fuses to give rise to a zygote is called fertilization. The species involved in this are able to interbreed afterwards. Thus, the option [C] is incorrect.

The random or sudden changes in the genome of an organism are known as mutation. It is not necessary that mutation exists in further generations. Thus, option [E] is incorrect.

The transformation of existing species into a new one or the splitting of existing species into daughter species, where there is no lineage species formation, is known as speciation. In this case, the new species are unable to produce an offspring when fertilized with an existing one.
Hence, the correct answer is option (D).

Note: The current population of the world is about 7.8 billion. The population could be categorized as expansive, constructive and stationary. The most common cause of speciation is geographical isolation.