05-13-2008, 08:28 PM
BaseballMan Wrote:It was a summerâs day in a monastery garden in Czechoslovakia over 100 years ago. Most of the monks saw nothing special about the pea plants growing there. To one of them, however, they were of great interest because he was performing scientific experiments with them.
What particularly fascinated Gregor Mendel was the way in which the plants handed on their characteristics to the next generation. 'What could happen', he thought, 'if I crossed a white-flowered plant with a red-flowered? Would the next generation have red flowers or white? What if I crossed a tall plant with a short one? What height would the offspring be?'
As Mendel performed these experiments and carefully analyzed the results, he realized that he had discovered some fundamental laws concerning inheritance. Greatly excited, he published his findings in a scientific journalâbut the scientific world ignored Mendelâs work completely. Discouraged, he abandoned his research. When he died in 1884, Mendel had no idea that 20years later, he would have become world famous as the founder of a new science. Mendelâs work is now regarded as the beginning of the science of genetics, the study of inheritance.
In the preceding chapters we have looked at the rise of evolutionary theory and the evidence of the fossil record. Now we must consider whetherâas is generally claimedâthe findings of genetics support the idea of evolution.
Mendel published his findings in the late 1860s at just the time when Darwinâs theory was becoming immensely popular. Mendel published in a reputable journal and his paper was widely circulated and certainly known about. Yet it was not until 1900, 16 years after Mendelâs death, that the work was rediscovered and its importance realized.
Why ignored?
Why were such vital discoveries ignored? The answer almost certainly is that they conflicted with Darwinâs theory of evolution. This is seldom admitted today, yet it is still true that what Mendel discovered disproved one of Darwinâs most important assumptions. This is demonstrated by the fact that after Mendelâs work was rediscovered, Darwinian evolution suffered a temporary eclipse. After a while, evolutionary thinking re-emerged in a slightly different form which was said to be quite consistent with Mendelâs genetics. As we shall see, however, the two are not consistent and both cannot be true.
What did Mendel discover that spoke against Darwinâs theory of evolution? This can best be answered by considering what he actually did. Mendel crossed various races of edible peas. When a red-flowered plant was crossed with a white-flowered, the offspring were found to be red-flowered. Mendel then crossed these red offspring with each other and found that they produced offspring of their own in the ratio of 3 reds:1 white.
We can best understand this by considering the genes involved in these crosses. A gene can be considered as a unit which determines a particular characteristic, in this case flower color. It can exist in one of two forms, one giving rise to red flowers and the other to white. The offspring of the original cross of red-flowered plants with white were all red-flowered, although they did in fact possess both a gene for red-flower and a gene for white.
Mendel concluded that the red gene must be dominant to white, so that any plant that possessed them both would be red. When these red plants were bred with each other, it was possible for two white genes to come together and so give offspring that were white. The chance that the offspring would receive at least one red gene is 3:1, as the diagram shows below.
Mendel's experiment
Mendel found that when he interbred the red-flowered plants obtained as the offspring of his original cross, he got white flowers as well as red. Darwinâs theory rested on the assumption that in such a case as this, the white characteristic was a new character acquired by the young plants which their parents had not possessed. After all, a race has got to acquire new characteristics if it is ever going to evolve.
http://www.answersingenesis.org/creation...netics.asp
Your guy completely missed the point on this one. It seems he only took what he thought has occurred in science and twisted it to fit his viewpoint.
Mendel's discoveries did not conflict with Darwin's evolution, they merely solved a problem with the theory. Darwin believed in blending inheritance, i.e if one parent is tall and the other is short they will produce medium sized children, and all children from then on will be medium sized. This seemed plausible, but it isn't quite true. What we now know thanks to Mendel's discoveries is that genes must separate during gamete (sex cell) formation. There may be two or more forms of these genes (alleles), some genes (dominant) may mask the effect of other genes (recessive). Mendel believed this all happened by chance, or independent assortment, but we now that's not all that can happen.
Mendel's studies showed the genes may mix to produce an intermediate phenotype (the observed characteristics of a gene), but the gene is not lost or blended.
Messages In This Thread
Darwin's impact -- The bloodstained legacy of evolution! - by BaseballMan - 05-12-2008, 12:55 PM
Darwin's impact -- The bloodstained legacy of evolution! - by BaseballMan - 05-12-2008, 12:56 PM
Darwin's impact -- The bloodstained legacy of evolution! - by thecavemaster - 05-12-2008, 02:14 PM
Darwin's impact -- The bloodstained legacy of evolution! - by BaseballMan - 05-12-2008, 03:05 PM
Darwin's impact -- The bloodstained legacy of evolution! - by thecavemaster - 05-12-2008, 04:50 PM
Darwin's impact -- The bloodstained legacy of evolution! - by launchpad4 - 05-12-2008, 10:08 PM
Darwin's impact -- The bloodstained legacy of evolution! - by thecavemaster - 05-12-2008, 11:08 PM
Darwin's impact -- The bloodstained legacy of evolution! - by ComfortEagle - 05-12-2008, 11:23 PM
Darwin's impact -- The bloodstained legacy of evolution! - by Coach_Owens87 - 05-12-2008, 11:56 PM
Darwin's impact -- The bloodstained legacy of evolution! - by BaseballMan - 05-13-2008, 09:08 AM
Darwin's impact -- The bloodstained legacy of evolution! - by BaseballMan - 05-13-2008, 09:13 AM
Darwin's impact -- The bloodstained legacy of evolution! - by BaseballMan - 05-13-2008, 09:20 AM
Darwin's impact -- The bloodstained legacy of evolution! - by BaseballMan - 05-13-2008, 09:29 AM
Darwin's impact -- The bloodstained legacy of evolution! - by Coach_Owens87 - 05-13-2008, 08:28 PM
Darwin's impact -- The bloodstained legacy of evolution! - by launchpad4 - 05-13-2008, 09:48 PM
Darwin's impact -- The bloodstained legacy of evolution! - by launchpad4 - 05-13-2008, 09:52 PM
Darwin's impact -- The bloodstained legacy of evolution! - by BaseballMan - 05-14-2008, 12:25 PM
Darwin's impact -- The bloodstained legacy of evolution! - by ComfortEagle - 05-20-2008, 04:11 AM
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