Question

second group was fed food containing mostly maltose. after eight generations apart when the flies were re-introduced, they would no longer interbreed. they bred only with flies of like eating habits and they had become two different species. speciation resulted in biodiversity!
use the text to choose all of the correct statements about speciation?
a in the case of the galapagos finches, biodiversity occurred because different species flew to different islands.

b allopatric speciation results when a geographic barrier separates members of a population.

c diana dodd imposed a geographic barrier on fruit flies.

d one premise behind speciation is that in any population, variation exists.

e during allopatric speciation, members of a population change in order to survive in their habitat.

f during the formation of the grand canyon, a population of squirrels were separated. we would expect today, that there are two species of squirrels in the grand canyon.

Explanation:

The text describes speciation (formation of new species) and Diana Dodd’s fruit fly experiment (separated groups by diet, not geography, leading to reproductive isolation). Key points:

• Allopatric speciation requires geographic barriers (B is correct).
• Variation in populations is foundational for speciation (D is correct).
• Diana Dodd used diet, not geographic barriers (C incorrect). Other options lack text support or are misstated.

Answer:

B. Allopatric speciation results when a geographic barrier separates members of a population, D. One premise behind speciation is that in any population, variation exists.