Directional selection is a type of natural selection that favors one extreme phenotype over the mean or another extreme. Examples of directional selection include giraffes that have long necks and the darkening of London's peppered moths after the Industrial Revolution.
Stabilizing selection, also known as purifying selection, is a type of natural selection in which genetic diversity decreases as the population stabilizes on a particular trait value. An example of stabilizing selection is birth weigh in humans.
Disruptive selection is a type of natural selection that shows a preference toward the reproduction of genetic material at the extremes within a population.One of the most studied examples of disruptive selection is the case of London's peppered moths.
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This chocolate is most likely milk chocolate made in the United States.
Usually blood transports nutrients
An area with unifying characteristic is called as a region. The region is a broad geographic area, which is differentiated from other because of the similar features. In a region one or more than one types vegetational climax might be present. It is the continuous and extensive part of the surface. The area in a region is indefinite.
Hence, the given blank can be filled with region.