Explain positive negative selectionsSolutionPositive and ne

Explain positive & negative selections

Solution

Positive and negative selection are to aspects of selection occuring in nature. They occur on organisms to either help them evolve or to remove deleterious effets in the organism.

Positive selection: It is also called Darwinian selection. The genotypic and phenotypic variants increase in population tiil they are fixed in the population. The selective pressure that leads to this fixation is termed positive selection. It is like you take a running test of 10 kids. Whoever runs fastest gets selected.

Negative selection: It is also called purifying selection, it means that selection suppresses changes that cause deleterious impacts on the fitness of the host. Examples like deleterius mutations are not fixed in a population. The relative fitness (w) is small, thus reducing the genotypic and allelic frequency at each generation.