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Evolution:
History of the idea of Evolution
Background information about Darwinian evolution, Primordial Earth and Dennett.
Includes information about Darwin's original theory of evolution by means of natural selection.
Information about what modern scientists think of infant Earth.
What Daniel Dennett (philosopher) thinks of evolution.
Go to the Think Quest page.
It is often questioned why nobody had "seen" evolution as Darwin did. The truth is all of the evidence Darwin collected had already been collected. Scientists before Darwin hadn't thought of evolution because of other beliefs. For example, faith in Christianity and Plato's theory that the physical world was a mere shadow of changeless, eternally distinct and immutable ideas (For example, cookies may all look the same, but each one is still unique in a way. These cookies all had to be made from the same mold. This mold was Plato's idea of eternally distinct and immutable ideas) which were of completely different thought than that of Darwinian evolution. It was like seeing a picture (that could be seen differently from many different perspectives) in one way, which preoccupied the minds of scientists prior to Darwin.
In 1859, Charles Darwin published On the Origin of Species by Means of Natural Selection or the Preservation of Favored Races in the Struggle for Life, which described evolution by means of natural selection. The book is now recognized as being responsible for making the theory accepted and understandable in the scientific world. Darwin understood that an animal species would develop slowly, through many generations, as the forces of the environment gradually selected for certain survival traits. Darwin did not understand, however, how the traits were transmitted. This was the one flaw in his theory that would not be solved until 1869.
French naturalist Lamarck was one of many who opposed Darwinism. Lamarck believed the natural habits of a creature would inevitably modify the creature's genetic structure. For example, a giraffe would gain a long neck by continually stretching and reaching for the treetop's trees. The giraffe's offspring would then inherit this trait. This theory has long been proven wrong. This theory would have ended along with the 18th century if it were not for the Russian Revolution when Stalin placed a scientist named Lysenko as President of the Soviet Academy of Sciences. Lysenko supported all research attempting to validate Lamarckian evolution while also supporting all research attempting to invalidate Darwinian evolution. After Stalin's death in 1953, Lamarckian evolution finally came to an end.
In 1869, Gregor Mendel, an Austrian monk, experimented with peas to determine the laws of inheritance. His original purpose was to help a fellow monk in growing the best possible peas. He published the results of his experiments, which laid down the basic laws of inheritance. Unfortunately, however, his results were not discovered until the 19th century. Finally, when Mendel's discoverings were found, scientists found that traits were changed by mutation. Thus, random mutations, for better or worse, gave advantages and disadvantages to the creatures.