Ohio Assessment for Educators (OAE) Integrated Science (024) Practice Exam

What type of selection results in the split of a single curve into two distinct groups?

1. Directional selection

2. Disruptive selection

3. Stabilizing selection

4. Non-directional selection

The correct answer is: Disruptive selection

Disruptive selection is the process that leads to the division of a single phenotypic distribution into two distinct groups. This type of selection occurs when environmental conditions favor individuals at both extremes of a trait distribution, while individuals with intermediate traits are selected against. As a result, this can create two distinct 'peaks' in the distribution of traits within a population, reflecting a divergence in traits rather than a shift towards one end of the spectrum. In the context of evolution, disruptive selection can foster speciation, as it encourages the development of two separate groups that may adapt to different ecological niches or environments. This divergent evolution can lead to increased biodiversity by contributing to the formation of new species.