A continental population of insects has blue, red, green, and black variations. The color is controlled by the interaction of two genes, one with two alleles, the other with three alleles.
A piece of driftwood carrying two green insects and five red insects floats in the ocean for several days and washes up on a small island where the insect species did not previously live. The seven insects establish a new population on the island that increases in number significantly over several generations.
Which of the following statements correctly compares the island population with the original mainland population?
A)Red is dominantly inherited in the island population, while on the mainland green is dominant.
B)The island population has lower genetic diversity than the mainland population.
C)The island population is more likely to experience competition with other insect species than the mainland population.
D)The island population size is increasing, while the mainland population is decreasing.

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Hint: Genetic variation could be defined as a measure of the genetic differences that exist within a population. The genetic variation of a complete species is usually called genetic diversity. Genetic variations are the differences in DNA segments or genes between individuals and every variation of a gene is called an allele.

Complete answer:
Genetic variation refers to diversity in gene frequencies. Genetic variation can check with differences between individuals or to differences between populations. Mutation is that the ultimate source of genetic variation, but mechanisms like reproduction and genetic drift contribute thereto similarly.
It is providing out of blue, red, green and black variations of insects, only red and green insects established a replacement population on the new island. Since these four colors are controlled by two genes, the new population could have either of the colour of insects. It's an example of the founder effect. The island population will have lower genetic diversity than the mainland population because small populations usually have less genetic diversity than large populations.

The founder effect is the reduction in genetic variation that results when atiny low subset of an outsized population is employed to ascertain a replacement colony. The new population could also be very different from the initial population, both in terms of its genotypes and phenotypes. In some cases, the founder effect plays a task within the emergence of the latest species.
The founder effect could be a phenomena that happens when atiny low group of people becomes isolated from a bigger population. Irrespective of what the first population seemed like, the new population will resemble only the individuals that founded the smaller, distinct population. The founder effect is because of the randomness that accompanies selecting atiny low group from a bigger population. The smaller the population, the upper the prospect that the little population doesn't represent the larger population. If the few organisms that migrate or get separated from the parent population don't carry the identical frequency of alleles because the main population, the resulting founder effect will cause the population that separated to become genetically distinct from the initial population. This could cause a brand new subspecies of organisms, or maybe entirely new species given enough time.

Hence, the correct answer is option (D)

Note: The founder effect can occur because of many alternative circumstances. The founder effect are often because of geographic isolation, when atiny low population of people migrated to a brand new area. During this case, the gap or obstacles between the 2 populations make interbreeding impossible, and also the new populations become genetically distinct over time. In another scenario, a mutation may cause a population of organisms to become reproductively isolated from the parent foundation. Without the flexibility to interbreed with the larger population, the tiny population becomes distinct. If successful it'll grow into a replacement species. Mutations and random allele changes in small populations are collectively referred to as genetic drift, and also the founder effect could be a piece of genetic drift.