Dark grey. Dark grey horses will have a light black coat, mane and tail. Brown. Brown is a very common horse colour and sometimes it can be hard to tell if horses are brown or black. There coat, mane and tail will all be brown from a light tan colour to a dark chocolate colour.
Genetic variation is a fact that a biological system â individual and population â is different over space. It is the base of the genetic variability of different biological systems in space.Genetic variation is based on the variation in alleles of genes in a gene pool.It occurs both within and among populations, supported by individual carriers of the variant genes. Genetic variation is brought about by random mutation, which is a permanent change in the chemical structure of a gene.enetic variation is based on the variation in alleles of genes in a gene pool. It occurs both within and among populations, supported by individual carriers of the variant genes. Genetic variation is brought about by random mutation, which is a permanent change in the chemical structure of a gene.
Genetic drift is a change in gene frequency within a population due to chance instead of natural selection. If the population is small, then there can be considerable genetic drift, which can change the gene frequency quite drastically. Think of the genetic variation of a population as a bowl of jelly beans with all sorts of colors, representing healthy genetic variation.