Monday, August 25, 2003

Survival of the...science

As with other sciences, evolution is now in practical use within modern technology. This is due, in part, to the invention of PCR (Polymerase Chain Reaction). It allows more efficient studies of genetics. PCR opens the door into how all species relate to each other. Exploration of this interconnectivity allows much quicker identification and treatment of old and new diseases. The use of applications based on biological studies of evolvution is benefiting our society. It will soon become part of our daily lives. Soon, denial of evolution will be equivalent to saying that the Earth is a flat, or that heavier objects fall faster than lighter objects.
There are examples of evolution’s survival of the fittest principle within our own species. There are traits in the human species that are fighting for dominance.
One trait in the Western Culture is lactose persistence. 75% of our population (U.S.) can properly digest lactose (from milk) our entire lives. This is a newer trait that has become dominant because of the long history of our use of milk in our daily diet. In other cultures, at least 75% of the population becomes lactose intolerant after the age of weaning. These are cultures that historically did not have access to milk on a daily basis, and so carry the older trait which naturally causes the weaning of a child. This older trait used to be necessary for survival, but now is unimportant.
Where lactose persistence is succeeding, there is another trait that is failing in the tropics. There is a genetic adaptation which allows an individual to be more resistant to malaria. But if a man and woman (who carry this trait) procreate, their children may have sickle cell anemia. This is an example of a genetic trait that benefits the individual, but not the species. If left alone, the trait will likely die out eventually. Or maybe it will lead to further adaptation that does not cause sickle cell anemia.
More rapid examples come to us in the form of viruses and bacteria. These species evolve yearly. Understanding of their origins (made possible by PCR through biological studies of evolution) allows us to combat them more effectively. This will eventually develop into technologies that will be apart of our daily lives, like flying in an airplane or satellite TV.

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