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The "theory" of evolution, as Stephen Palumbi puts it, is not a theory, it is hard fact. He cites insects that have evolved resistances to pesticides, such as the diamondback moth and its uncanny, recently evolved ability to evade the effects of Bt toxin. He points to lizards that have evolved longer legs to scale larger trees when relocated to lands with such trees, wolves that have evolved into dogs and chimpanzees that have evolved into humans (Palumbi). Rapid evolutionary change also quite clearly exists. Perhaps best showcased by the ongoing struggle with bacteria that evolve faster than the antibiotics that kill them. AIDS and HIV dodge and thwart antiviral chemicals as soon as they are introduced. Rapid evolution change is quite real (Palumbi). Taking the Good With the Bad A point often stressed, particularly by Dr. Palumbi, is that there is no universal "good" and "bad" when it comes to evolution. Evolution is blind to what is helpful to a creature and what is not. The helpfulness of any particular trait is determined long after it is administered, by the lifespan and proliferation of the organism with the trait (Palumbi). An example of evolution's blindness is apparent in an experiment involving fruit flies. A sticky board was lowered, ever so lightly, onto a mass of fruit flies. Those with curled wings stuck to the board and those fruit flies with normal, straight wings were unaffected. The flies captured on the board were then released to breed and as expected, the offspring all had curly wings, utterly useless for flying. Those flies, of course, promptly died (Palumbi). At no point did "Nature" intervene with the helpful observation that curly wings are a mark of death and work to push evolution in a more helpful direction. Nature rolls dice. Another example of blind evolution is the genetic "defect" hemochromatosis. Thousands of years ago, there lived an isolated group of people who, as their luck would have it, resided in an area with devastatingly low iron in the soil. As a result, people were unable to take in proper amounts of iron and developed anemia and died. Rather quickly, though, a trait emerged that caused the blood to retain iron over great periods of time so that a person with the trait would have stores of it. As a result, the first person (or people) with this trait lived long, healthy lives and had many children. Of course, the children inherited that iron-retaining trait and eventually, only people with the trait lived in the area. The people evolved out of necessity. Today, iron is plentiful. Many foods are fortified with iron and the technology exists to improve the amount of iron in soil in nutrient poor regions. The result of this is that the iron-retaining trait or "hemochromatosis," is a liability. People who are born with this trait take in a normal amount of iron but their blood tries to retain it all. Severe liver damage is the result and people with the trait do not live long (Wired). What was a life-saver for some people is a death sentence for others. And over time, hemochromatosis will disappear as, the people who have it tend to die without mating and ultimately, it will be beneficial evolution that gifted the trait and beneficial evolution that will take it away. As humans we interpret evolutionary changes as good or bad, but although evolution's ultimate purpose is to give organisms a leg up, conditions can change faster than evolution can affect an organism enough to meet those changes. See: OPB's Evolution |