Posts Tagged ‘Darwin’

When Charles Darwin wrote “On the Origin of Species”, he wrote about the difficulty of determining the actual mechanism of change in species from generation to generation. He was quite sure that the environment played a role in the final outcome of things via a survival of the fittest system. The problem in the theory of evolution was not that the strong thrive and the weak perish, because that is obvious. The problem is how does a species actually evolve? Darwin rejected the idea of incremental change over a long period of time as the likely cause of evolution. Instead, he looked at domesticated animals and observed how they could change over several generations by selective breeding. He thought that a mechanism similar to this, some sort of selective breeding that occurred in the wild, was the most likely mechanism of evolution. The “selective” breeding would occur between organisms that happened to be in the right place at the right time under the right conditions and they also happened to have the right genes for producing a successful hybrid. His theory was, in essence, that change in a species occurred due to a “natural” and chancy form of selective breeding. It wasn’t random change, it was more like lucky change. His theory then goes on to state the almost obvious: those changes that result in better adaptations to the environment result in better survival rates.

Darwin borrowed from the environmental theories of Malthus and concluded that as supplies of food increased in nature and animal populations thereby increased that those individuals most suited to the environment would prosper more than those who had been born slightly less suited. It was the principle of survival of the fittest. These survivors would then breed and the next generation would have the traits of the survivors. This was Darwin’s theory of evolution. The problem was, as Darwin admitted, how, exactly, does this generational change occur?

Many people take Darwin’s theory of evolution and proclaim that it is based upon random changes that occur in genes and those which help an organism to survive lead to successful adaptations while those random changes that hinder survival result in population declines. Darwin never advocated a theory of random change. His theory was more like a theory of natural selective breeding where the strongest get to breed and their traits are passed on to the next generation, very similar to what he observed in the farms of England.

Recently, genetic scientists have discovered that Darwin was wrong. It turns out that genetic change does not have to happen by selective breeding. It can happen by direct impact of the environment upon an organisms DNA. This new discovery states that the vast majority of our DNA, usually referred to as “junk DNA”, is not junk after all. Much of the human genome has been decoded so that we know where the code is in our DNA for blue eyes, or our blood type or even if we have a predisposition to some forms of cancer. Yet, the vast majority of our DNA is referred to as “junk”. That’s because scientists didn’t know what its function was – or if it even had a function.

In an article recently published in the New York Times , Gina Kolata writes that gene switches in junk DNA, “play critical roles in controlling how cells, organs and other tissues behave”. She states that, “…the environment can affect disease risk. In the case of identical twins, small changes in environmental exposure can slightly alter gene switches, with the result that one twin gets a disease and the other does not.” It stands to reason that if the environment can change junk DNA and then cause a disease, it can also cause a change that results in resistance to disease or perhaps some other very different result. The real discovery here is that a mechanism has been discovered that can cause human DNA to rapidly modify itself in response to a factor in the environment. This must be the cause of evolution.

While the Times article is primarily focused on diseases being caused by exposing junk DNA to certain substances, it is only reasonable to ask whether this is in fact the mechanism of evolution. It is a direct connection between the body’s genes and the environment. Certainly, there will be cases where the environment contains toxins and these toxins will harm the DNA and cause disease. However, this is very likely the mechanism of evolution also. It is the way in which the body’s DNA senses that the environment is changing and tries to make the appropriate response. This is very likely the true mechanism of evolutionary change. It also explains why evolutionary change is, as Darwin noted, fairly quick and not a progression of minute changes.

It seems that Darwin’s notion of selective change occurring because of the coincidence of the right circumstances for the right individuals is not the likely explanation for evolution. It seems far more likely that our “junk” DNA is not “junk” at all, and it is this DNA (it actually comprises about 90% of our DNA) that results in “evolutionary” change. It seems that just as we are able to make conscious adaptations to our environment that there is another level of consciousness in our bodies, that we are unaware of, that is also continually working to optimize our body’s response to the environment and also that of the next generation of human beings.

Junk DNA is how evolution works.


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I happen to like Golden Retrievers. They seem to be intelligent and friendly and make the perfect family dog – in my opinion anyway.  It’s interesting to note that if you wanted to buy a Golden Retriever in 1850 you couldn’t.  Not for any money in the world.  Why? Because they didn’t exist.  Golden Retrievers were created by breeding a Retriever with a Tweed Water Spaniel in the late 1800’s.

I don’t think I would care much for having a Lhasa Apso, however.  Too much chance of accidentally stepping on it. They’re really, really small and don’t look or act anything like a Golden Retriever. The Lhasa Apso was bred exclusively in Tibet about 2,000 years ago and was not found in the west until about one hundred years ago.  At first glance, if you didn’t know better, you might not guess that both of these animals are actually dogs.

DNA evidence has shown that dogs became a separate breed apart from wolves about 100,000 years ago. If you look at the diversity in dogs, from Chihuahuas to Saint Bernards to the vicious and often banned Presa Canario, it becomes even harder to believe they are all examples of the same species, let alone all descended from wolves.  How could a Lhasa Apso be a modern day wolf?  But they are and their DNA proves it. So do the written records of the modern day 19th and 20th Century breeders who created most of our breeds by mating selected individual dogs. These latter day breeders were unknowingly the agents of artificial evolution. By using selected breeding they were able to accomplish in a hundred years what nature might have taken thousands of years to produce, if at all. (Why would nature ever create a Lhasa Apso anyway?)

Most of our domestic animals, horses, cows, chickens and so forth have been bred by farmers over the centuries in order to optimize some property or other.  The same is true for the vegetables and fruits that are grown on our farms.  Farmers have long known that they could alter the size, shape, and taste of animals and plants by selective breeding.  In the process they have created a variety of breeds and variations, all descended from a handful of ancestors.  In some cases there is only a slight resemblance between today’s descendants and the ancient origins of the various breeds and cultivars.  Once again we have humans deliberately creating evolved organisms in a much shorter time that would normally occur by the chance matings in nature.  The results, like those with dogs, can show such wide variation that it might be hard to believe that a particular plant or animal had descended from a certain distant parent.

If you look at people in America today and compared them with the people who lived here 200 years ago you would notice something different right away: on the average we are quite a bit taller than the people of those days. Not because of selective breeding but because we have a more nutritious diet.  We are also a lot heavier on the average too, because we are overfed.  We also suffer from diseases, such as heart disease, that were essentially unknown 200 years ago.  Is this a sort of evolution?  Well, if by evolution we mean change, then of course it is. If you care to look, you can see we are immersed in a constantly changing world. Almost every living species, for one reason or another, is continually evolving – some slowly and some quickly.  So why do only 39% of Americans believe in evolution? Why do 61% of Americans deny it?

Good question, when all you have to do is open your eyes to see it. It is undeniable.  It is the way of the world.  So what is the problem and why do the fundamentalist churches teach their members that evolution cannot and does not happen? And why do the people who belong to these churches deny the evidence of their senses and agree with the leaders of these churches?  It comes down to how evolution happens and what is evolving. Even those people who are determined to believe that the Adam and Eve story is literally true have to explain how we have now become an assortment of Eskimos and Kenyans, Irish and Tibetans, Native Americans and Russians, Australian Aborigines and African Pygmies. If there is no evolution then why do we all look so different, and which of us looks most like Adam and Eve?And are the others, who don’t look much like Adam and Eve anymore therefore less perfect? I would have to believe that, because the Bible originated in the Middle East, our best guess would be that Adam and Eve must have looked sort of Semitic, right? I mean, what else makes sense? So…what happened to the rest of us?  Why don’t we look Semitic too?

Part of the issue the churches have is the random change theory. You know, evolution is caused by completely random changes in DNA that sometimes works out and sometimes doesn’t.  This is the theory put forth by many proponents of evolution, but it is not necessarily correct, even if Darwin proposed it himself. This theory completely ignores selective breeding and the potential, newly discovered, adaptive capabilities found in the epigenome.  The idea that randomness is the only engine of change in the world is a philosophy put forth by people who, for one reason or another, want to prove that there is no need for an ordered mechanism in evolution, because then someone might say this orderly mechanism is proof of the existence of God.  However, we have just shown that people are capable, all by themselves of causing dogs to evolve.  The presence of a causative mechanism or the effect of random mutations in DNA cannot be used to either prove or disprove the existence of God. It’s time we got past this artificial argument and accepted the reality we live in. Our world is a constantly changing and mysterious world, and we are part of the change and mystery.  To deny this is to deny reality – which, apparently, is what 61% of Americans are happy to do.

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