What Is the Difference Between Natural Selection and Selective Breeding?

Nature's Manipulation

• Natural selection is a process that happens as a result of the natural environmental conditions and changes within an organism's habitat. The environment is always changing. For example, a drought occurs and drives grazing animals into new territory to look for water. In this case, animals with an ability to go long periods without water will survive while the ones that cannot will perish. This occurrence is nature selecting the organisms most suited for survival to continue living, hence the term natural selection.

Human Manipulation

• Selective breeding is different from natural selection because the change that occurs--which results resulting in modified organism behavior and survival--is generated by humans, not nature. Humans do many things to an organism's environment to induce change in organism behavior, including isolating animals in laboratory environments and spraying pesticides on open farm fields. The result of this is that organisms no longer have natural choices concerning food, breeding partners, and habitat. Humans' intentional interference changes the entire life course of the organism.

Evolution

• The result of natural selection is evolution. Each species of organisms has many variations of genetic expression within it. Over time, the changes in the natural environment alter the mating habits of organisms and cause the genetic traits of individual organisms to change. Over large amounts of time, organisms can change so much they barely resemble their ancestors at all.

Hybridization

• When applying selective breeding techniques, the result is hybridization. Through selective breeding, organisms that express certain dominate genetic attributes (phenotypes) are manipulated to breed together. This is done through artificial insemination, manipulating the transfer of pollen to stamen in plants or encouraging natural copulation between two animals. This technique is commonly used by farmers to increase crop yield and to discourage pests. Human interference is required for selective breeding.