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What is Darwinism



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“Darwinism” is a pejorative reference to a theory more properly known as The Theory of Evolution or Natural Selection. First developed by Charles Darwin a few years before the American Civil War, the theory states that in any given population of living organisms natural variations occur.

 When conditions favor specific traits, the creature who possess the trait will be more able to survive and pass the trait to its progeny. Over time, the population will consist of more individuals with the positive trait who will breed in greater numbers. Over time entirely new organisms may develop out of a parent population, especially if the individuals form small, isolated breeding populations.

 For all the controversy, this is actually not such a shocking idea. Animal breeders have been successfully creating new dog breeds since the days of the caveman. No one disputes that the giant Great Dane and the diminutive Yorkshire Terrier are both dogs, as anyone who has watched to his dismay as an unguarded female purebred whelped a litter of nondescript offspring sired by the local Lothario can attest.

 No one imagines that God personally created every dog breed, cat breed or color of rose, the role of human selection is just too obvious. But when it comes to natural selection, things get heated.

 Darwin did most of his research on the isolated South Sea Galapagos Islands. Located on these islands were populations of finches whose ancestors reached them only with great difficulty. Since the original parents were few and in-breeding took place regularly for generations, it was easy to see changes in what had once been identical birds.

 Depending on whether the birds had greatest access to insects, seeds or fruits, their beaks shifted accordingly to facilitate success. For example, a heavier beak would indicate a seed eater since such a beak breaks hard seeds apart easily. On the other hand, for a bird feeding from insects located in narrow cracks, a graceful, thin beak would have greater usefulness.

 Likewise, adaptations in neck length seen in subspecies of Galapagos Tortoise where ascribed to selection by diet. In islands where low-growing plants were more common, shorter necks prevailed. In adjacent islands where animals primarily fed leaves from shrubs, longer necks were more common.

 Common misconceptions bedevil this theory. For example, many people believe that evolution “makes” things happen. Not true. If the Galapagos turtles or finches did not naturally produce offspring that were somewhat different from each other ,than the theory would not work. When an adverse change in conditions occur, extinction or death, is more common than adaptation.

 In the 19th Century, an early theory called Lamarckism suggested that Giraffes became the long-necked creatures they are because they consistently stretched their necks. Later, this theory was taken up by a Soviet scientist named Lysenko. For more than a generation, Soviet Orthodoxy embraced this theory because it fit with the concept of a “New Soviet Man,” a changeable being who could be shaped by the will of the State.

In keeping with this concept, farmers were instructed to plant in unsuitable climate areas in the vain belief that the plants could be forced to adapt. Scientists who challenged this orthodoxy were sent to labor camps in great numbers. Famine resulted.

The mechanism that explains how natural selection actually works was discovered by a Roman Catholic Monk named Gregory Mendel who discovered dominant and recessive traits while breeding peas at the turn of the last century. His theory is called classical genetics and it works like this:

 Dominant traits are traits of the parent that are always inherited by the offspring and are visible in the first generation. Recessive traits are traits that are hidden until one or more parents who carry the trait breed. In the next generation, a certain portion of the offspring will display the dominant trait, some offspring will carry the trait and pass it on, but look no different from the ones without the trait, while others display the recessive trait.

For example, suppose tallness is a dominant gene. If the offspring of two tall parents and two short parents breed, in the first generation every child would appear to be tall, however; out of every four children from such a marriage, two tall children might possess a recessive gene for shortness. They would look identical to their tall siblings, but if these two mated and had children some of their children would be short.

 Classical genetics differs from Lamarckism or its Soviet variant Lysenkoism because it stresses the role of sexual cells in passing on inheritance. According to Mendel, what counts is the presence or absence of dominant or recessive traits that are carried on the sex cells of the plants or animals, that is to say on the ovum and pollen of a flowering plant or the sperm and eggs of an animal.

 Classical genetics insists that no matter what you do to a parent, you cannot force evolution because change is carried by the sex cells only, and nothing done to the other cells of the body, known as somatic cells, will change this fact. Just as in the ancient myth of the innkeeper who cut feet off to fit guests to their beds, generations of foot-cutting will still result in children with two normal feet, just as in African countries where women stretch their necks for cosmetic reasons, children are still born with normal-sized necks.

 The only way that an organism will change is if a mutation or change, occurs on the sex cells and is successfully passed on to offspring because it improves the odds of survival or breeding or at least does no harm. Over the slow progression of millions of years, environmental pressures combined with in-breeding in populations slowly induces the changes known as evolution.

 Some organisms are well-adapted to their environments and their modern descendents are essentially unchanged from the days of the dinosaurs. Horseshoe crabs are an example. These animals are called living fossils.

 Although “Darwinism” has become a social hot button, The Theory of Evolution is well-established with over a century of evidence behind it. Scientific developments in genetics, taxonomy, medicine, botany, zoology and many other sciences are grounded in its ideas.



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