Things that we're never meant to stick

"Artificial selection has resulted in plants that are more disease-resistant, cows that produce more milk, and racehorses that run faster. One must wonder what will come next. Under what circumstances should humans be artificially selecting plants or animals."

Artificial selection is the intentional breeding of certain traits, or a combination of traits. Unlike natural selection, artificial selection is for the reproduction of plants and animals with the most desirable traits. Why would anyone want to do this anyways? The first occurrences of selective breeding occurred in plants, the winters were very harsh in north America and the summers were too short to properly harvest the wheat, so they artificially created a wheat which was more cold-resistant. This sparked an idea to apply artificial selection to many more things... but as particular genes are being produced and reproduced doing much good, there are consequences...

Artificial selection also known as selective breeding is usually done by crossing two members of the same species which possess dominant alleles for certain genes, and is crossed with another member which has desirable dominant traits. Both of these members have dominate genes for the desirable characteristics, when they are crossed-bred they will produce some offspring that will show all of theses desirable characteristics. The world of today is in need of plants and animals which posses favourable traits, such as high crop yields, resistance to disease, high growth rate and many other phenotypical characteristics which will benefit the organism/species in the future. Our human population is increasing at an alarming rate, and the world is already incapable of feeding everyone. Inorder to try and sustain our already unsustainable population we look for a quick solution out of this mess..

An example of selective breeding to help accommodate our growing population is the Belgian Blue cattle. It is a heavily muscled cattle, known as "double-muscling". The Belgian blue cow has a natural mutation of a gene that codes mysotatin (a protein that counteracts muscle growth). It's nonfunctional mysotatin, results in accelerated lean muscle growth, which means more meeat to feed people. Double-muscled cows also experience dystocia, because of the narrowing of their birth canals and have to be caesareaned.

It definitely is an advantages to both the species and humans to recreate these traits that may benefit the organism. However, the continuous breeding of certain genes risks losing some of the other genes from the gene pool in the process, and it's irreversible. The specific word for this is called “in-breeding depression” where favorable advantageous genes mean that some other less desirable genes are phased out in the future, and it is more advantageous for organisms to remain heterozygous. The downside of in-breeding depression is the lack of genetic diversity. The lack of diversity in the gene pool which is prepared for wide range scenarios such as good shortage or an epidemic is lost, and there is a possibility of the species becoming extinct because of this.Humans realize the extinction of one species can also have a devastating effect, knocking the balance of an entire ecosystem. Is it right for us to risk losing an entire species because of our own needs?

In conclusion I think selective breeding can be seen as good or bad, and I don't know enough about it to state my opinion. So I just hope this article helped you in choosing a side.

Sources:

http://www.biology-online.org/2/12_selective_breeding.htm
http://en.wikipedia.org/wiki/Belgian_Blue
http://www.messybeast.com/inbreed.htm