Question

According to the biological species concept, which of the following statements is not correct?
A. To be considered a species, a population must be reproductively isolated from other species.
B. For a new species to arise, it must be geographically isolated from its parent species for long periods of time.
C. Organisms that are phenotypically identical yet have distinct mating behavior are considered distinct species since they do not naturally interbreed.
D. Organisms that can interbreed and can produce sterile offspring are considered distinct species.

Answer 1

Hint: Ernst Mayr gave the biological species concept in 1942. The theory of biological species is applicable to all living organisms except fossil species and organisms which can reproduce asexually or with extensive self - fertilization.

Complete Answer:
According to the biological species concept, organisms belong to the same species if they can interbreed to produce viable, fertile offspring.

Option A: According to the biological species concept, for a population to be considered species, they should be closely related organisms that are very similar to each other and are capable of interbreeding and producing fertile offspring. Geographical isolation from other species is not required. Therefore, this is the correct option.

Option B: According to the Biological species concept, geographic isolation is a common way for the process of speciation to begin. Rivers change course, mountains rise, continents drift, organisms migrate, and what was once a continuous population is divided into two or smaller populations. Therefore, this is an incorrect option.

Option C: According to the biological species concept, phenotypic similarities are not required for two populations to be considered the same species, interbreeding between them is necessary. Therefore, this is an incorrect option.

Option D: According to Ernst Mayer’s biological definition of species, organisms that can interbreed and produce sterile offspring are considered distinct species. Therefore, this is an incorrect option.

Thus, the correct option is A)To be considered a species, a population must be reproductively isolated from other species.

Note: It is to be noted that the concept of the biological species connects with the idea of a species to the process of evolution. It is so because the members of a species can interbreed and the species as a whole has a common gene pool, a collection of gene variants.