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."
The architects of
Neo-Darwinism: Theodosius Dobzhansky,
Ernst Mayr, , and Julian Huxley.
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.