A small number of birds arrive on an island from a neighboring larger island. This small population begins to adapt to the new food plants available on theisland, and their beaks begin to change. About twice a year, one or two more birds from the neighboring island arrive. What effect do these new arrivalshave?O A. Their arrival represents a colonizing event.O B. Their arrival will likely prompt genetic drift.O C. Their arrival tends to retard adaptation to the new food plants.O D. Their arrival speeds the process of speciation.O E. Their arrival tends to promote adaptation to the new food plants.

Speciation: Speciation is how a new kind of plant or animal species is created. Speciation occurs when a group within a species separates from other members of its species and develops its own unique characteristics Speciation occurs when a group within a species separates from other members of its species and develops its own unique characteristics. The demands of a different environment or the characteristics of the members of the new group will differentiate the new species from their ancestors. Answer: Option A : Their arrival represents a colonizing effect : wrong Because, Colonizing effect occurs when a large amount of individuals of a species migrate from one place to another and colonize the new place. thus, small number of birds arriving cannot show colonizing effect. Option B : Their arrival will likely prompt genetic drift : wrong Genetic drift is a random fluctuation of gene variants in any population. This occurs when the amount of variant forms increases by chance over time. This lead to change in allelic frequencies and no change is observed here in the allelic frequencies. Option C : Their arrival tends to retard adaptation to the new food plants : wrong This will happen when the old species is present only with the addition of any new species in a particular population. hence it is wrong as new species are migrating in small numbers. Option D : Their arrival speeds the process of speciation : correct Because the addition of new species accelerates the speciation process.