Question

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.

Answer 1

The correct option is B The island population has lower genetic diversity than the mainland population.

It is given that out of blue, red, green and black variations of insects, only red and green insects established a new population on the new island. Since, these four colors are controlled by two genes, new population could have either of colour of insects. It is an example of founder effect. The island population will have lower genetic diversity than the mainland population because small populations usually have less genetic diversity than large population.

Thus, the correct answer is 'The island population has lower genetic diversity than the mainland population.'