Question

Random genetic drift in a population probably results from
A) High genetic variable individuals
B) Interbreeding within this population
C) Constant low mutation rate
D) Large population size

Answer 1

Hint:Let us first understand what is genetic drift. Genetic drift is a process which results in huge changes in the population within a short span of time.

Complete Answer:
>Genetic drift is an evolution mechanism in which allele frequency in a population is changed due to the sampling error from one generation to another.
>The frequency of characters which have less adaptive values may be increased in a small population by a chance event.
>In a small population not all the alleles which are representatives of that species may be present. In such a small population a chance event may increase the frequency of a character that has little adaptive value.
>In isolated places and islands, genetic drift plays a vital role when it comes to the origin of new species.
>In such conditions, the characteristics of the species in a small population will be different than that of the species found in the main population.All these changes will lead to the formation of new species.
>Such deviations may even lead to speciation or formation of a new species. The interbreeding of the population may result in the development of the new species.
>New species are also formed as a result of interbreeding within the population.

Therefore the correct answer is (B) interbreeding within this population.

Note:We should remember that along with genetic drift, natural selection is also responsible for the change in the allele frequency. In genetic drift change in allele frequency is by chance but in case of natural selection, change in allele frequency is due to differential reproductive success.