Two populations of birds with somewhat different coloration live on two different islands. When birds from the two populations are brought together, they produce young whose appearance is intermediate between the two parents. These offspring can successfully breed with each other or with birds from either parent population, and all offspring of these pairings appear intermediate to various degrees. According to the biological species concept, the two populations on different islands ___.

represent a single species

Explanation:

According to the biological species concept, a species can be defined as a group of organisms that can potentially interbreed (i.e., mate) in order to produce viable and fertile offspring. Based on this concept, the cohesion forces that maintain the integrity of the species as a single group are 1-interbreeding between its members and 2-reproductive isolation mechanisms that prevent successful mating between organisms from different species. In this case, both bird populations represent the same species because when individuals of these populations are brought together they can interbreed to produce viable and fertile offspring.