Heart-shaped ivies, sometimes called sweethearts, have a leathery look and are rarely lobed. Miniatures are slow growers and the smallest ivies. Their largest leaves are no bigger than 3/4 inches long and 1/2 inch wide; they make good terrarium subjects. An ivy plant can fall into more than one of these categories.
The second main cause of genetic variation is due to the high degree of neutrality of most mutations. Most mutations do not appear to have any selective effect one way or the other on the organism. The main cause is genetic drift, this is the effect of random changes in the gene pool. In humans, founder effect and past small population size (increasing the likelihood of genetic drift) may have had an important influence in neutral differences between populations.
Your genes have alleles, which are different forms of the same gene. Alleles are like a code for your body that determine hair color and eye color, height, and other genetic features. Genetic variation is the variation in alleles and genes, both within and among populations.Think of a population as a family unit.ene flow is the movement of genetic information between different populations. This method increases genetic variation because introducing new alleles into a population increases the amount of diversity. The more alleles available in a population, the more variation that can occur.