Describe the movement of the water molecules at cold temperatures.

The molecules of cold water are moving slower and are a little closer together. If students do not notice a difference, move the slider all the way to the left again and then quickly to the right.

Explanation:

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).