Artificial selection is a scientific term used to describe the breeding of plants and animals for desirable traits and not necessarily those that would allow the offspring to better survive in the wild. It is also known as selective breeding, artificial selection, and unnatural selection. The process can be considered the exact opposite of natural selection.
How is it done?
Artificial selection is relatively easy to accomplish. A specific plant or animal is chosen because it has a specific heritable genetic trait that the breeder desires. The plant or animal is then bred with another of its kind with a similar trait, resulting in offspring with a higher potential to display the specific trait. This cycle can be repeated with the offspring until the specific trait is achieved at the desired level.
Examples of artificial selection:
There are dogs, plants, cows, crops, cats and many other selections of living things around the world. There are over 150 different dog breeds, from tiny chihuahuas to giant Great Danes, but they are the same species and all are descendants of wolves. if a breeder wanted a dog with a curly coat, he or she would allow curly-coated dogs to breed and not allow them to breed with straight-coated dogs. Over the years, the plants with desirable characteristics are grown by man and their numbers increase. Meanwhile, plants without these characteristics are less likely to survive as they are not provided with the fertilizers and pesticides by man. Eventually, the species of the plant will evolute. Cows are artificially selected to make them stronger, grow faster, reproduce healthy and strong cattle and to produce more milk. These super cows grow stronger muscles and live longer than usual cows.
Good or Bad?
Inbred offspring are one of the potential dangers of too much artificial selection. Some traits are so rare that they can only exist in one or two family lines. If the trait is recessive, two members of the same line (relatives) may have to be bred together in order for the trait to be visible. In animals, this can result in genetic defects and other serious problems.
The results of artificial selection are easy to see. The domestication cycle of dogs (canines) being bred by their owners in order to emphasize less aggressive traits has gone on for thousands of years, and has resulted in hundreds of different breeds that look almost nothing like their grey wolf ancestors. Dairy cattle are bred in hopes of producing more milk, but some lines now suffer from increased infections and fertility problems. Persian cats that are bred for extremely flat faces often develop respiratory problems and may have trouble eating. All of the listed traits that are bred for do not help the animals survive in the wild, but do make them more desirable to their owners.
In my opinion this has gone way out of line. breeding animals and plants? who's next, us?!
Should we artificially select plants or animals?
Studies have shown that artificial selection has a lot of potential applications in the field of medicine and which remains a pursuit of the future. It shows that artificial selection can even be put into humans. For example, stem cell research. The ethical questions that have begun to be asked in the setting of stem cell research has remained a hot topic in recent years. But it seems impossible that research will ever be legal. Stem cells are able to become any cells of the body and are a perfect match to each person. Artificial selection lets researchers to select the best stem cells from their Petri Dish. So, once these stem cells are allowed to distinguish into organs, the best organs can be selected so the recipient receives the best possible benefit.
Drug production can also assist from artificial selection. Some of our medications are made by genetically modified bacteria. Selection technology can allow laboratories to breed viruses that are able to make the mixtures at the fastest rate, improving the efficiency of medicine production.
In my opinion, i strongly disagree with selective breeding. I think it's wrong to choose how someone or thing should appear in public. Yet again there's always advantages and disadvantages in this subject. Disadvantages would be for show animals such wild kitten eatingas some dogs, it is practised quite strictly by breeders aiming at a certain look which is set down as the breed "standard". Many Dalmation puppies are euthanased because they do not exhibit the breed standards for example, so there are serious moral questions to it too.Too much close interbreeding to obtain certain cosmetic traits can also result in the amplifying of inherent illnesses; like the bulldogs mentioned above, or German shephered dogs with hip problems and so on. In fact, these issues are rapidly worsening in recent years with dogs in particular. The advantages would be that it can produce fitter, stronger animals or animals of a higher yield of milk, meat or eggs for example. Can produce animals better suited to survive in poor climates or marginal conditions, thus preserving human food supplies and saving life, and can ensure the eradication of hereditary sickness in some blood lines.
Seals, sharks, polar bears, and sea otters are just few of the animals that are examples of species being endangered. This all happens because of us humans. For example, we take tigers, lions, foxes to make fur out of them for us to be able to dress warmly and show off. This should not be happening. It is cruelty to skin animals and to use them. Another example would be shark fins. We use them for our own luxury. But if you could take all these animals and selectively breed them, why wouldn't you? They would no longer be at risk and we would feel proud of saving them.
In conclusion, I think, yet again, that we are to blame for everything but at the same time this could be used in a good way. For animals, it could be used in a way that could bring us good. What if we were to engineer chickens into making more eggs? That would be a useful thing for everyone because they are a source of high protein. With humans though, why put chemicals and different hormones in a child that is not even born yet? Why make them suffer just because the parents wanted that child to have green eyes, or blonde hair? In the end, there are both positive and negative sides to artificial selection. Maybe we could get plants to grow twice as fast so that we can have more photosynthesis which could give us more energy to wake up in the morning and go to school.
sources:
http://en.wikipedia.org/wiki/Artificial_selection
http://animals.howstuffworks.com/pets/dog2.htm
http://www.windows2universe.org/cool_stuff/tour_evolution_7.html
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