Question

question 2 of 10
what must happen for speciation to occur?
a. gene flow must increase.
b. a population must be isolated in some way.
c. all alleles in the population must become fixed.
d. asexual reproduction must occur.

Explanation:

Speciation is the process by which new species form. For speciation to occur, a population must be isolated (such as through geographic isolation, behavioral isolation, etc.). Isolation prevents gene flow between populations. Over time, genetic differences accumulate due to mutation, natural selection, and genetic drift in the isolated populations. If these differences become significant enough, the populations can no longer interbreed successfully, leading to the formation of new species.

• Option A is incorrect because gene flow (movement of genes between populations) would prevent speciation as it keeps populations genetically similar.
• Option C is incorrect as it is too extreme; not all alleles need to be fixed for speciation.
• Option D is incorrect as asexual reproduction alone does not lead to speciation in the context of what is required for new species formation (speciation concepts are mainly focused on sexually - reproducing organisms in this context).

Answer:

B. A population must be isolated in some way.