Thursday, August 16, 2012

The Efforts of Neo-Darwinism



A group of scientists who were determined to reconcile Darwinism with the science of genetics, in one way or another, came together at a meeting organized by the Geological Society of America in 1941. After long discussion, they agreed on ways to create a new interpretation of Darwinism and over the next few years, specialists produced a synthesis of their fields into a revised theory of evolution.

The scientists who participated in establishing the new theory included the geneticists G. Ledyard Stebbins and Theodosius Dobzhansky, the zoologists Ernst Mayr and Julian Huxley, the paleontologists George Gaylord Simpson and Glenn L. Jepsen, and the mathematical geneticists Sir Ronald A. Fisher and Sewall Wright.5

To counter the fact of "genetic stability" (genetic homeostasis), this group of scientists employed the concept of "mutation," which had been proposed by the Dutch botanist Hugo de Vries at the beginning of the 20th century. Mutations were defects that occurred, for unknown reasons, in the inheritance mechanism of living things. Organisms undergoing mutation developed some unusual structures, which deviated from the genetic information they inherited from their parents. The concept of "random mutation" was supposed to provide the answer to the question of the origin of the advantageous variations which caused living organisms to evolve according to Darwin's theory-a phenomenon that Darwin himself was unable to explain, but simply tried to side-step by referring to Lamarck. The Geological Society of America group named this new theory, which was formulated by adding the concept of mutation to Darwin's natural selection thesis, the "synthetic theory of evolution" or the "modern synthesis." In a short time, this theory came to be known as "neo-Darwinism" and its supporters as "neo-Darwinists."

Yet there was a serious problem: It was true that mutations changed the genetic data of living organisms, yet this change always occurred to the detriment of the living thing concerned. All observed mutations ended up with disfigured, weak, or diseased individuals and, sometimes, led to the death of the organism. Hence, in an attempt to find examples of "useful mutations" which improve the genetic data in living organisms, neo-Darwinists conducted many experiments and observations. For decades, they conducted mutation experiments on fruit flies and various other species. However, in none of these experiments could a mutation which improved the genetic data in a living being be seen.

Today the issue of mutation is still a great impasse for Darwinism. Despite the fact that the theory of natural selection considers mutations to be the unique source of "useful changes," no mutations of any kind have been observed that are actually useful (that is, that improve the genetic information). In the following chapter, we will consider this issue in detail.

Another impasse for neo-Darwinists came from the fossil record. Even in Darwin's time, fossils were already posing an important obstacle to the theory. While Darwin himself accepted the lack of fossils of "intermediate species," he also predicted that further research would provide evidence of these lost transitional forms. However, despite all the paleontologists' efforts, the fossil record continued to remain a serious obstacle to the theory. One by one, concepts such as "vestigial organs," "embryological recapitulation" and "homology" lost all significance in the light of new scientific findings. All these issues are dealt with more fully in the remaining pages of this site.

5 Michael Denton, Evolution: A Theory in Crisis. London: Burnett Books, 1985

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