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Evolution Less Accepted In U.s. Than Other Western Countries


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1.) how is evolution one of the most fundamental truths of science. i can think of a hundred other things that wiegh much more than evolution. it is not that important. i think since you hold an oppinion oppisite of the fundy's you inflate the situation. i can name several cristians that could care less if scientist are studing evolution. does it matter if they hold an opinion that it is not important. of course not. how does that stop scientist from discovering stuff.

 

Freeday:

 

I'll begin my response with two quotations from eminent biologists:

 

"Nothing in biology makes sense except in light of evolution." (Theodosius Dzobhanksy)

"Biology is the science. Evolution is the concept that makes biology unique." (Jared Diamond)

 

What most lay people don't realize about evolutionary theory is that it ties biology together. Before Darwin, biology was like stamp collecting. You had bunch of species, these species had structures but none of it made sense. Darwin's gift to biology was a set of problem solving strategies that allow us to understand why the living world has the features it does. I'll give two examples.

 

The first is one that comes up so much that it's almost trite but it illustrates what an amazingly powerful set of tools Darwinian thinking puts in the hands of biologists. Consider the peacock's tail. Now, this structure has some fairly serious drawbacks, not the least of which is that it makes peacock's rather ungainly which has some fairly serious consequences for peacock's survival. Why would natural selection favor something like this? The answer is that natural selection doesn't, but sexual selection *does*. The proximate cause of the peacock's tail is the peahen. At some point in their evolutionary history, peahens started favoring males with long and garish tails. It's a great advertisement for health in that it's very hard to fake and if you are not in good health your tail will not be as spectacular. Now, does this actually work? Yes, in point of fact it does. Someone did an elegant experiment in which they took peacocks and docked the tails of those who had done well in the prior breeding round and grafted them onto the tails of peacocks who had done worse. They found that the peahens favored the males with the grafted tails. What good is it knowing this? Well, having confirmed that sexual selection can be a driving engine, biologists have begun looking elsewhere to see if there are features in humans that might be the result of sexual selection. Things like male facial hair, the hip-to-waist ratio in women, some racial characteristics *all* appear to be effects of sexual selection.

 

The second is finding DNA. What did one have to do with the other? Well, the missing piece of the puzzle when Darwin wrote Origins was a vehicle for inheritance. Evolution hangs upon inheritance and at the time, Darwin didn't know what could be responsible for transmitting traits through generations. By the early 20th century biologists had rediscovered Mendel so we had some idea of how inheritance worked but still not what actually transmitted it. This was what led to work that culminated in the discovery of DNA and its structure.

 

I'll actually throw in one more. Multiple-drug resistant bacteria. Here is an example where if more people--particularly more medical professionals--understood evolution we would not be in the fix we are in. Natural selection works, more or less, like this: In any given generation some individuals will have a genotype that leads to a phenotype that may or may not enhance their reproductive success. If the environment is such that having the main genotype leads to a phenotype that is more economical that will be the dominant type, however, should the environment change and the new phenotype confers some selective advantage then the new phenotype will become dominant. (I am grossly oversimplifying here but, again, I hope I'm communicating the gist.) Now, enter the bacteria. In any given colony there will be some specimen that are resistant to a given antibiotic. When people take antibiotics for colds or flus (both caused by viruses which aren't affected by antibiotics) and/or do not complete their full course of antibiotics then what happens is that the specimens that are resistant will gain a foothold. They may go into abeyance but they will have 'learned' a bit about how to resist that particular chemical. They pass this down to their descendants. Each time they are exposed to the antibiotic and the same thing happens (i.e. incomplete course) they learn a little more. In remarkably short time (TB was all but wiped out 35 years ago, staph was having a hard go of it and now both are back) because bacterial generations are *so* fast, you wind up with a strain that is all but immune to certain antibiotics. Doctors are now having to open up antibiotic treatments with far stronger medicines than they had to even ten years ago because we have inadvertently bred lots of multiple-drug resistant strains of TB, Staph and Strep (just to name a few). What makes this even more pernicious is that bacteria are able to do transpecific gene transfer so they can 'teach' other species of bacteria their good tricks.

 

Now, here is, perhaps, my most powerful example of what evolutionary thinking buys biology. Without a Darwinian framework there is simply NO way to think about that problem--none. What does evolution have to do with it? Evolution is the differential reproductive success of genotypes over generations which have affects on the phenotype of an organism. What I describe above is *precisely* that. In 1800, had we *known* what we know now about bacteria there would have been no way to understand what was happening. Long before the medical community caught on the biology community was expressing concern about the over use of antibiotics. Largely they were ignored and for the most part, a lot of lay people have no idea that there is a public health cloud on the horizon caused by the use of antibiotics in large factory farms and their overuse in medical treatment.

 

I could go on and on about what evolutionary thinking buys biologists but I think you get the gist of it. While it might *appear* that evolutionary theory is irrelevant it isn't, evolutionary theory is core to biology and if it's wrong, then biology is broken. I know that sounds like hyperbole but it's not. It would be akin to physics suddenly having to throw out thermodynamic or classical mechanic (not the tweaking of the latter post-Einstein but completely throwing it out and starting again). Evolutionary theory is that core the science of biology, it is the unifying concept of all of the biological sciences from molecular biology to population genetics to extinction studies.

 

Cheers

lf

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Someone did an elegant experiment in which they took peacocks and docked the tails of those who had done well in the prior breeding round and grafted them onto the tails of peacocks who had done worse. They found that the peahens favored the males with the grafted tails.

 

This experiment was featured in the Evolution series by PBS. We just recently checked out the set at our local library. Wow, it was amazing! I highly recommend it to everyone.

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