Question

Suppose that genetic drift in a population of salamanders results in color differences across the population's range. Over time, some salamanders become primarily brown, whereas other salamanders become mottled brown with black. Individuals from each group occasionally interbreed. Within each population, there is no genetically-based preference for mating with a brown salamander or a mottled salamander. This scenario represents what kind of evolution?

1) Macroevolution
2) Microevolution

Answer 1

The scenario described with color variation in a salamander population due to genetic drift without mating preferences represents microevolution, as it involves changes in a small scale within a population's genetic structure. Option 2 is correct.

Step-by-step explanation:

When considering genetic drift in a population of salamanders resulting in color differences, with some becoming primarily brown and others mottled brown with black, and given that there is no preference for mating within these color groups, we are observing a scenario of microevolution.

Microevolution refers to changes in a population's genetic structure, often manifested as variations in allele frequencies within a population over time. In the case of these salamanders, the lack of a genetically-based preference for mating means that while individual salamanders may express different phenotypic traits (such as color), the process affecting the evolution of the population as a whole is happening on a microevolutionary scale, not a macroevolutionary one. Therefore, this scenario represents microevolution, which is option 2).