An Introduction to Selective Breeding

Selective Breeding

Selective breeding is a process where organisms are bred to acquire certain traits. The aim of selective breeding is to either delete an undesirable trait of an organism or add traits that could be beneficial to its domesticators. For example, cows are bred to produce more milk, fatten faster or even for its aesthetic appeals. Similarly plants, especially flowers are selectively bred to create astonishing colors.  There are two methods of selective breeding, which includes:

Inbreeding

Inbreeding is a process where organisms with similar genetic lineage are mated, which is a painstaking effort to remove undesired traits among livestock’s. This process, in contrary to natural selection, which created fitter animals, inbreeding is a repeated process of breeding animals with similar traits causing them be totally unfit for nature and is solely dependent on its domesticators. According to Gregory Mendel, there is a probability out of four for all alleles to appear on an offspring, for instance one livestock has a dominant allele of having horns, therefore, it is bred with ones with horns reducing the probability for the offspring’s to have horns, and the process is repeated until having horns in that particular livestock became a recessive allele! This comes with a price; the animals would be easily subjected to genetic defections and is prone to be ill for many of its original traits acquired in years of evolution had been lost.

Out crossing

Out crossing is where people mated unlike species in order to create a new lineage of animals to serve their needs.  Out crossing is definitely more difficult than inbreeding because in many causes, sex cells of the candidates do not accept each other. However, it is possible to mate animals that are not in the same specie but within a family with similar homologous structure. When successfully bred, the offspring will not be able to reproduce because by out crossing, the domesticator had created new species with varied sex cells, therefore, its sex cells will not accept any other specie’s. A mule is a prime example of successful out crossing between a horse and a donkey. The mule combined favorable characteristics of horses and donkeys creating a versatile farm workhorse. The mule, like other out crossed organisms cannot reproduce, therefore, it would immediately become extinct if people no longer breed them.

A typical mule, an outcome of out crossing, note its iconic donkey like pointed ears and its horse like physique.