Difference Between Natural And Artificial Selection

What Is Natural Selection?

Natural selection is one of the basic mechanisms of evolution, along with mutation, migration and genetic drift.  Natural selection also referred to as “Survival of the fittest’’ is a process by which a species change over time in response to changes in the environment or competition between organisms, in order for the species to survive. The members of the species with the most desirable characteristics are able to produce the best-adaptable offspring. If a species is unable to adapt then it is at risk of becoming extinct.

Therefore, in natural selection those variations in the genotype (the entire complex of genes inherited from both parents) that increase an organism’s chances of survival and procreation are preserved and multiplied from generation to generation at the expense of less advantageous variations. 

Natural selection can lead to speciation where one species gives rise to a new and distinctly different species. It is one of the processes that drives evolution and helps to explain the diversity of life on Earth.

Charles Darwin’s theory of evolution suggested that different species have evolved from simpler life forms and that the organisms able to survive are those that have adapted best to their environment.

What You Need To Know About Natural Selection

1. Natural selection is whereby nature selects the individual with favorable variations for better survival in an environment.
2. Natural selection is a nature-based selection process.
3. Natural selection allows only the best or most favorable characters to be inherited over the successive generations.
4. Natural selection takes time. It takes about hundreds of years for new species to emerge.
5. It is random and occurs in all kind of natural populations.
6. The chances of survival for species in its natural environment are increased through natural selection.
7. Selection is generally based on the characters that are adaptable in all types of natural conditions.
8. It happens on a wide scale and in all types of organisms in a natural population.
9. Proportion of heterozygous in the population remains high.
10. Examples of natural selection include: The selection of long-necked giraffes, the selection of dark color moths and the change in the size and shape of beaks of birds upon the available food.

What Is Artificial Selection?

Artificial selection also referred to as selective breeding is a process of genetic modification whereby humans select desirable traits in plants and animals and perpetuates those traits in successive generations.

Artificial selection works the same way as natural selection, except that with natural selection it is nature and not human modification that result in changes. Artificial selection has long been used in agriculture to produce animals and crops with desirable traits. Domesticated animals are referred to as breeds, usually bred by a professional breeder whereas domesticated plants are referred to as varieties, cultigens, cultivars or breeds. Two purebred animals of different breeds produce a crossbreed and crossbred plants are referred to as hybrids.

The meats sold today are the result of selective breeding of chicken, cattle and pigs. Many fruits and vegetables have been improved or even created through artificial selection. For example, broccoli, cauliflower and cabbage were all derived from the wild mustard plant through selective breeding. Artificial selection appeals to humans since it is faster than natural selection and allows human to mold organisms to their breeds.

What You Need To Know About Artificial Selection

1. Artificial selection is the process by which animals and plants are chosen by the breeder to produce desirable and inheritable characters in the successive generations.
2. Artificial selection is a man-enhanced selection process.
3. Artificial selection allows only selected traits to be inherited over successive generations.
4. Artificial selection is a rapid process and happens within a specified time.
5. It is specific and usually occurs in domesticated populations.
6. The chances of survival of the new breed are less whether it is in animals or plants or any organism for that matter.
7. Selection is generally based on required character traits.
8. It promotes evolution of a few economically important plants and animals only.
9. Proportion of heterozygous in the population is reduced as inbreeding increases homozygosity.
10. Examples of artificial selection include: The breeding large dogs such as Bullmastiff or small breeds like Chihuahua and Boston Terrier; and cattle which can produce more milk.

Also Read: Difference Between Sympatric And Allopatric Speciation

Difference Between Natural And Artificial Selection In Tabular Form

Also Read: Difference Between K And R Selected Species