Genetic variation is important because a population has a better chance of surviving and flourishing than a population with limited genetic variation. Genetic diversity also decreases the occurrence of unfavorable inherited traits.Continue Reading
Genetic variation comes from mutations within DNA; the movement of genes from one population to another, or gene flow; and new genetic combinations resulting from sex. When a population contains genetics of individuals who vary significantly, some of the individuals in the group can possess traits that make them resistant to disease or cold, increasing the group's chance for survival when these individuals breed with the others. A small, isolated population's individuals may be forced to breed with close relatives, increasing the occurrence of genetic flaws. When inbreeding occurs, any genetic weaknesses found in the parents can be multiplied in future generations.
Genetic variation also helps organisms survive in different climates and environments. If the environment is unpredictable over time and includes a variety of diseases and predators, some differences among individuals increase the chances of some individuals surviving to reproduce, while others do not. In disease resistance, genetic diversity is important because a disease can decimate a homogeneous population in which all the individuals are equally susceptible to the disease.Learn more about Molecular Biology & DNA
The Hardy-Weinberg principle states that the genetic variation in a population stays constant over generations in the absence of disruptive factors. The concept predicts that when mating occurs randomly in a vast population, the allele and genotype frequencies remain consistent because they are in equilibrium.Full Answer >
Genetic variation is the result of mutation, gene flow between populations and sexual reproduction. In asexually reproducing organisms, some genetic variation may still result from random mutation.Full Answer >
Genetic drift is more likely to occur in small populations because when a mutation arises in a member of such a population, they, and potentially their offspring, constitute a much larger proportion of the population than a mutated individual would be in a larger population. As their offspring interbreed with others, the new trait is much more likely to become widespread. A larger population would tend to drown out mutations.Full Answer >
Genetic variation is important to evolution because it helps to maintain the health of a population by constituting alleles that may be useful in overcoming stresses such as diseases and pests. Without genetic variation, some of the fundamental mechanisms of evolutionary changes would not operate.Full Answer >