b) divergent selection c) directional selection. d) disruptive selection. Additionally, what are examples of directional selection? The result is a bimodal, or two-peaked, curve in which the … The other type of selections wouldnt make any sense to me. I dont believe the definition for disruptive selection favors two or more extremes. It is the rarest form of selection. In directional, one extreme is favored over the other. Key Terms. In this way, human activity resulted in directional selection. C) disruptive selection. It can be influence by humans. e) stabilizing selection. There does not appear to be a good example of disruptive selection in human evolution. eration. And this isnt sexual selection . Like directional selection, disruptive selection can be influenced by human interaction. Disruptive selection appears to be the rarest form of natural selection and, indeed, there are few well-documented cases of it. In disruptive selection, the normal curve hits extremes and bypasses levels of a trait in the middle. It just favors extreme over normal. In stabilizing, the normal trait is favored. In the grassy fields, the light-banded snails escape bird predators. Disruptive Selection. Figure%: The effect of directional selection on trait distribution Disruptive Selection In disruptive selection, selection pressures act against individuals in the middle of the trait distribution. British land snails are an example of disruptive selection. Human birth weight is a classic example of the results of: a) genetic drift. Disruptive selection occurs when extreme values of a trait succeed over intermediate values of the same trait, in a given population. In the darker forest, the dark snails survive and the light-banded snails are eaten. stabilizing selection. Selective pressures will work in the advantage of the longer neck giraffes and therefore the distribution of the trait within the population will shift towards the longer neck trait. The occurrence of large or small beak sizes among seed crackers in the absence of medium-sized beaks is an example of A) directional selection B) stabilizing selection C) disruptive selection D) none of the above. directional selection: a mode of natural selection in which a single phenotype is favored, causing the allele frequency to continuously shift in one direction; disruptive selection: (or diversifying selection) a mode of natural selection in which extreme values for a trait are favored over intermediate values; stabilizing selection: a type of natural selection in … After suitable Despite its rarity, however, disruptive selection may be very important for the emergence of species. Example: Giraffes with the longest necks are able to reach more leaves to each. disruptive selection: ... 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