Question

question 9 of 19
two hypothetical populations of rabbits live on a mountain, one at low elevation and the other at high elevation. rabbits at the low elevation experience a mild climate and have short fur, whereas rabbits at the high elevation are exposed to cold conditions and have long fur. there are no geographic barriers separating the ranges of the two populations.
an ecologist finds that in both the low and high elevation populations, there are a few rabbits that have intermediate fur length.
she notes that the rabbits with intermediate fur length can successfully mate and produce offspring with rabbits that have short or long fur.

what is the most likely explanation for why some rabbits have intermediate fur length?
the rabbits with intermediate fur length live in a different area and are migrating through the two populations.
the rabbits with intermediate fur length are from an isolated population.
the population at low elevation is experiencing genetic drift.
there is gene flow between the low and high elevation populations.

Explanation:

Gene flow refers to the transfer of genetic material between populations. Since there are no geographic barriers, rabbits from low (short fur) and high (long fur) elevations can interbreed. Intermediate fur length likely results from the mixing of genes for short and long fur through mating between the two populations, which aligns with the observation that intermediate fur rabbits can mate with both short and long fur rabbits. The other options are less likely: no mention of a different area/migration source, no isolation, and genetic drift does not explain intermediate traits from two distinct populations.

Answer:

There is gene flow between the low and high elevation populations.