Directional selection is a mode of natural selection in a phenotype that is single and favored. Making the allele frequency continuously move in one direction. Stabilizing selection also know as ambidirectional selection a type of natural selection where genetic diversity is decreased because the population slowly stabilized on a particular trait value. Another name for disruptive selection is diversifying selection, this is because it describes the changes in the populations genetics where extreme values for a trait are favored over intermediate values. Unlike stabilizing selection, disruptive selection the varity of the trait is increased and the population divides into tow distinct groups. To make the distinction between the three types of selections, here is an example of stabilizing selection. The weight of a newborn human if too light lose heat rapidly and tend to get infectious diseases. It also works the other way around, if the baby is too heavy they endanger not only themselves but also their mothers when passing through the birth canal. To help stabilize the birth weights a small range of birth weights had been selected to assure the stabilization. A good example for directional selection is the breeding of the greyhound dog. Breeders had selected from a group of hounds that were the fastest and then from their offsprings they selected again the fasted hound. It soon became a dog who could run up to 64km. The fur color of rabbits is a good example for disruptive selection. This rabbit has a incomplete dominance between white and black, now if the rabbit was to live in a enviorment with black and white rocks then the rabbits that would survive would be the black and white furred rabbits. However the gray furred rabbits that stand out and are unable to blend into their enviorment would be likely eaten which is when disruptive selection comes in. To ensure the species survival the selection allows only black and white fur to be showed but not the gray since it would decrease the species rate of survival.
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