Genes: Selective Breeding.

Humans have used science to produce variations of organisms.  This process is called selective breeding; the two types of selective breeding are hybridization and inbreeding.  Luther Burbank is a plant breeder known for being the greatest selective plant breeder of all time.  Burnamk used hybridization to cross different organisms together and use the best of the parent traits for the offspring.  Hybridization led to plants that had characteristics that increased food production.  Inbreeding is continued breeding of organisms with similar traits.  This is how dogs are kept pure breed and get a pedigreed certificate.  Selective breeders can use hybridization or inbreeding to create variations of organisms.