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Macro-evolution and micro-evolution

The Facts concerning Micro and Macro Evolution

Macro-evolution is evolution on a large scale. It is essentially the evolution of one species into another. For example, it is thought by most scientists that dinosaurs evolved into modern day birds. Micro-evolution on the other hand is small scale evolution. It is the evolution that takes place within a species. It is also known as adaptation. For example, a snowshoe hare that lives in Canada may have smaller ears than one that lives in the U.S.A. This is thought to be because smaller ears lose less heat than large ones and the snowshoe hare with small ears has a retableive advantage in cold climates.

Observations on Micro and Macro Evolution

If macro-evolution has taken place in the past then why do we see such differences between species? It seems to me that if species slowly change over long periods of time then what we should see are blended species. In fact I do not think that we would actually see what we call species at all. As one organism changes slowly through time there should not be such distinctive differences between species.

Micro-evolution appears to have much more evidence that we can actually record with our senses. There are many examples of a species adapting to changes in its environment. Common examples include the different ear sizes of snowshoe hares, hibernating patterns of bears or even humans getting a suntan in the summer. However, one the most commonly cited examples of micro-evolution may not be so well documented after all. Let's look at the evolutionists favourite example of micro-evolution: antibiotic resistance in bacteria.

The story we are always told goes like this. Antibiotics are used to kill bacteria. At first these antibiotics are very effective at killing bacteria. Over time, as the bacteria reproduce at rapid rates, there are mutations in some of the bacterial cells. These mutations give those individual bacteria resistance to that particular antibiotic. Those bacteria then reproduce and there is then an entire population of bacteria resistant to that antibiotic. That is how the story is told.

But here is another story. I put a potted plant on a window sill and then opened the window. I fertilized and watered the plant. Soon the plant grew really tall. Now, what caused the plant to grow? Was it the sun coming in through the open window? Was it the water? How about the fertilizer, the fresh air or even the birds that were singing in the trees? How do I find out? I use the scientific method that I learned in fifth grade. I do an experiment. I vary just one of the possibilities. Through a series of controlled experiments I can determine that water, fertilizer, air and sunshine are all necessary for the plant to grow. I can also determine that bird songs, beautiful though they are, have nothing to do with plant growth. At least nothing that I can detect scientifically.

Now, back to our bacteria. How would I go about determining whether a genetic mutation was responsible for the bacteria becoming resistant to an antibiotic. I would have to do controlled experiments. The first thing I would have to do would be to sequence the DNA in every bacterial cell in the culture. Without that baseline as a starting point how would I know whether a mutation had actually taken place? Now that every bacterial DNA is accounted for I would administer an antibiotic to one culture but not to another. I would then test those cultures for antibiotic resistance. Let's say that the culture that was given the antibiotic does indeed show resistance to that particular antibiotic. Now what? I would then need to sequence the DNA in every bacterial cell until I found a mutation. Let's say I find one. Now what? How do I determine that the mutation was indeed the cause of the antibiotic resistance? I would need to separate the bacteria in that culture into two different cultures. One culture would contain the bacteria with the mutation and one would have bacteria without the mutation. I would then administer the antibiotic to the two cultures. If the culture without the mutation was destroyed and the culture with the mutation was not I could reasonably assume that the mutation was responsible for the antibiotic resistance. But to be certain I would have to identify the protein that the mutated gene produced. I would then have to isolate that protein and see if it rendered the antibiotic harmless to that particular bacteria. Of course, if there was more than one mutation occurring at the same time things would get much more complicated.

How do scientists so quickly determine that antibiotic resistance was caused by a mutation? Do scientists actually sequence the DNA in every bacterial cell and then try to put it back into the cell without killing that cell? Highly unlikely. When the DNA (or RNA) in a single bacterial cell is sequenced the cell is destroyed. Without knowing the original DNA sequence there is no possible way to determine whether a mutation actually took place. So why do scientists so freely assume that a mutation took place and that this mutation is responsible for antibiotic resistance? They assume this only because it agrees with what is already believed to be true: that mutations are responsible for evolution. This is not science. Science is based on observation and repetition

One more story should do. When I was young I got chicken pox. I was sick for a little while and then I got better. Later when my own children got chicken pox I was not afraid to be near them. I had no fear of getting chicken pox again. Had I mutated to "become" resistant to the chicken pox virus? No, the DNA in my cells already had the code required to produce proteins known as antibodies specifically made for the chicken pox virus. These antibodies recognized the virus responsible for chicken pox and rendered it harmless. My cells could do this even though they had never before encountered that particular virus. There were no mutations involved in this process.

Could it be the same with bacteria? Maybe. Maybe not. How do we find out? We do controlled experiments just like scientists should. Until that happens we can never be sure of the cause of antibiotic resistance. Claiming that antibiotic resistance is the result of genetic mutations is not science. It is conjecture pure and simple.

I will make one more observation on the terms macro and micro-evolution. Micro-evolution is defined to be small changes within a species. Macro-evolution is the long term accumulation of micro-evolution that results in a new species. When I was in school (many years ago) the terms micro-evolution and macro-evolution were not even used. When I was in high-school biology the terms used were adaptation (or adaption) and evolution. Today it is micro-evolution and macro-evolution. The term adaptation (or adaption) is synonymous with micro-evolution. It is my opinion that the term evolution caused such an uproar within our mostly conservative population that evolutionary scientists coined the term micro-evolution to replace adaptation. The reason for this is because micro-evolution can be readily observed. Therefore the term "evolution" becomes an accepted part of our vernacular and does not seem so threatening. The prefixes macro- and micro- do not mean much to a non-scientific person and so the term evolution becomes acceptable where it otherwise might not be. It is my opinion that the term micro-evolution came about only because of opposition to Darwin's evolutionary ideas.


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