Artificial selection is the process of changing the characteristics of animals by artificial means. For example, animal breeders are often able to change the characteristics of domestic animals by selecting for reproduction those individuals with the most desirable qualities such as speed in racehorses, milk production in cows, trail scenting in dogs. Artificial selection can also be unintentional. It is thought that domestication of crops by early humans was largely unintentional.
Charles Darwin first utilized this term in contrast to natural selection. He noted that many domesticated animals and plants had special properties that were developed by intentionally encouraging the breeding potential of individuals who both possessed desirable characteristics, and discouraging the breeding of individuals who had less desirable characteristics.
Natural selection is the process by which heritable traits that make it more likely for an organism to survive and successfully reproduce become more common in a population over successive generations. Artificial selection is the exact same process but with inteference from outside factors, such as human intervention.
Artificial selection results into inbreeding, and inbreeding holds potential problems. The limited gene pool caused by continued inbreeding means that harmful genes become widespread and the breed loses productivity. Any negative physical traits and health disorders get locked in. Inbreeding leads to animals or plants that are so genetically identical that they can be considered clones. This does not ensure variation. Without variation species are more prone to diseases and natural disasters, thus the potential to the endangerment and extinction is very high. If a selective breed was put into a situation, i.e. isolation, the founder effect can occur. Even if the slightest amount of the population contained a ‘bad’ gene or mutation its predecessors are more likely to inherit that gene, and if it is harmful it can lead to endangerment and/or extinction. Inbreeding and artificial selection are forms of genetic engineering. The processes involved the moving of genes that nature had never intended or had an inability to do so, this can lead to unexpected consequences. Genetic engineering can have devistating and irreversible effects. The effects can take years to show up and even if they do, it may be irreversible and nothing can be done about it. Genetic engineering (artificial selection/inbreeding) can have harmful and irreversible effects that can lead to the endangerment and even exticntion of species.
German shepherd was pure bred for herding sheep and protecting flocks from predators. But modern careless breeding has promoted disease and other defects.
The aftermath of the process can be very harmful to the animals/plants as well. An example of this are the genetically altered chickens. These chickens are bred to grow faster and much bigger than their feral ancestors, also these chickens produce no feathers, this is done to reduce time on processing the chicken to the consumer’s dinner table (feathering), this in turn makes the chickens more prone to viral infections and diseases.
A featherless chicken.
There is a reason why artificial selection is an acceptable practice, it is that they are promoting the more desirable genes and in turn creating a more healthy population. Artificial selection can remove dangerous and unhealthy genes from the population, granted that the ancestral population did not have any harmful genes. Artificial selection in plants can lead to new plant-types that may posses medical and pharmaceutical advantages. All the desirbale traits of the species are present and that can ensure the reproductivity and well-being of the species. Breeds can be specified to do a job with great efficiency and productivity.
The bloodhound is a large breed of dog that was bred originally to hunt deer and wild boar, later specifically to track human beings by scent.
Other than the fact that selective breeding has phenotypic and some genetic advantages, the genes of the species that are genetically altered can have dier consequences. It is mother nature’s job to select which traits are suppose to be inherited, not ours. We are playing the role of mother nature when we practice inbreeding and genetic engineering. These processes can have harmful effects and we have no one to blame but ourselves.
Work Cited
"Artificial Selection." Oracle ThinkQuest Library. Web. 25 Jan. 2010.
"Genetic Engineering Advantages & Disadvantages - Biology Online." Life Science Reference - Biology Online. Web. 25 Jan. 2010.
"The German Shepherd Dog in Word and Picture -." Wikipedia, the free encyclopedia. Web. 25 Jan. 2010.
"Individual Breed Results for Purebred Dog Health Survey - The Kennel Club." The home for dog owners and those working with dogs - The Kennel Club. Web. 25 Jan. 2010.
"PROS AND CONS OF INBREEDING DOGS, Inbreeding Dogs." Dog Breed Info Center. Web. 25 Jan. 2010.
"Pros and Cons of Mutations." THE MESSYBEAST. Web. 25 Jan. 2010.
I agree with your statement that it is Mother Nature's job to select the traits that are supposedly to be inherited by ever organisms and not ours. It's true that human must be very careful when dealing with artificial selection because we don't want the "original ones" to become extinct. We can't do anything to reverse the gene alterations when undergoing artificial selection, as you stated, it's irreversible.
ReplyDeleteHowever, although much of these are true, we can't still deny that artificial selection is still very beneficial to us. We are able to produce more nutrition-filled fruits and vegetables and more milk-producing cows.
Yes. I agree with what you're saying, Timothy. Artificial selection can lead to inbreeding, which in turn does have negative effects. To think, something that was meant to be positive can end up being negative. It's terrible that through artificial selection there is the risk of either species being endangered or becoming extinct. Is this really worth it, if all that’s really being taken into consideration is ourselves? I mean, if you really think about it, we are being selfish in selecting characters that WE want, and not what’s best for the species itself to survive. I think you used excellent examples to prove some of the points made in your blog entry. Like you stated, we shouldn’t play the role of mother nature, and just allow things to occur the way they’re supposed. I‘m not saying that we shouldn’t intervene at all. I believe we can be there to give a little push, but not to take all matters in our hands. After all, we don’t know what kind of destruction we can cause. I know I may be blowing it out of proportion a bit with the words I selected, but I think we just need to know our place at times. Overall, great blog entry! :)
ReplyDeleteYo Tim! I like when you wrote, "Artificial selection results into inbreeding, and inbreeding holds potential problems. The limited gene pool caused by continued inbreeding means that harmful genes become widespread and the breed loses productivity. Any negative physical traits and health disorders get locked in. Inbreeding leads to animals or plants that are so genetically identical that they can be considered clones."
ReplyDeleteThinking about that, I think that if we do continue artificial selection which leads to inbreeding, we will in the future have a loss of some species of dogs, cows, and who knows, anything else we artificially produce!
So maybe we need to ease off the artificial selection for a bit and focus on what we have. I liked this blog and thought it was well thought out! :)
nice pics of animals...
ReplyDeletei love pets...
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