Animal breeders often change the characteristics of domestic animals by deciding which two animals should reproduce with each other. Of course, the animals or plants whose qualities and characteristics are more desirable will be reproduced more. Their numbers will increase while the animals or plants which have less desired qualities and characteristics will decrease for they won't be nourished as well.
For example with plants, if their traits are not desired, they will not be provided with the necessary fertilisers and pesticides to help them survive as well as they potentially could. The species will become unbalanced.
Humans want to get the best traits and therefore, mass reproduce and artificially select for these traits to be obtained. Artificial selection is quite harmless but like anything else, if you do too much of it, it will have long-term effects and can create dramatic changes.
Advantages:
Artificial selection holds many potential applications in the field of medicine. These areas include stem cell research, genetic conditions and medicine production.
Stem cells have the ability to become any body cell and can match each individual perfectly. Artificial selection benefits stem cell research so that only the best stem cells are selected. Once stem cells are allowed to differentiate into organs, the best organs can be selected. Therefore, the recipient the best possible benefit.
For those who have genetic conditions, artificial selection offers hope for them through DNA therapy. In DNA therapy, a normal gene is placed into a virus genome which is introduced to the affected human after becoming harmless. These viruses are able to integrate normal human DNA into the human cells expressions so that the defected protein can be replaced by the one necessary and appropriate. Humans are able to use artificial selection to breed the best viruses in order to create the best protein and therefore, introduce then to individuals so they can function normally. DNA vaccines have the same concept.
Some medications are created by genetically modified bacteria. Artificial selection technology allows for the breeding of viruses to be created at a fast rate, improving the efficiency of drug and medicine production.
Artificial selection will be able to provide plenty of long-term as well as long lasting benefits in the for our investment in it when it comes to the field of medicine including all listed above: stem cell research, genetic conditions and medicine production.
Disadvantages
Artificial selection can be inhuman as well as cause mutations which can lead to new problems.
Though it has its benefits, the aftermath of artificial selection isn't always pleasant for the plant or animal. An example of this inhumane process is the new way of breeding chickens. Humans have them reproduced without feathers. This is not good for the chickens because chickens without feathers tend to suffer more than normal birds. For males, they may be restraint from mating since they cannot flap their wings. Also, not only chickens but birds in general, are more susceptible to parasites, harmful insects, and sunburn without if they do not have feathers.
Through artificial selection, you never know when a mutation will occur. New mutations can be good, bad, or not even make a difference. Mutations create evolutionary consequences if passed on to the next generation. Some mutations can actually be very harmful.
The circumstances which lay out what's acceptable or not require not going too far. It is amazing that our world has the technology to select artificially. It has its very beneficial advantages pertaining to potential applications in the field of medicine: stem cell research, genetic conditions and medicine production. But it also has its disadvantages: inhumanity and mutations. I think that as long as humans don't take it to far by considering what other side effects would occur, artificial selection is a good thing and worth the risks because the benefits of artificial selection involve further research and therapy for humans.
Sources:
http://www.helium.com/items/804222-artificial-selection-and-its-application-to-medicine
http://www.associatedcontent.com/article/13619/naturally_artificial_selection.html
http://www.biology-online.org/2/13_genetic_engineering.htm
