Is the molecular evidence conclusive?
(The following material was researched in Phillip R. Johnson's book, Darwin on Trial.)
DNA and RNA comparisons
By comparing differences in the molecular sequences of DNA and RNA molecules, biochemists try to classify species by their degree of similarity at the molecular level. The validity of these calculations is controversial. For example, all frog species look similar, "but their molecules differ as much as those of mammals, a group which contains such fantastically diverse forms as the whale, the bat, and the kangaroo."(Johnson, 1991). Humans and apes do have similarities at the molecular level. However, similarities do not prove a common ancestry.
Cytochrome c.
Another molecular comparison that is made uses cytochrome c., a protein. Looking at cytochrome c. however shows that there is little difference in the percentage of divergence between bacteria and many other organisms, including seame plants, silkworms, and humans.
Mitochondrial DNA
Mitochondrial DNA has been analyzed in the study of human descent. One analysis showed that all contemporary humans were descendants of a woman who lived in Africa less than 200,000 years ago. If this is true, than all the hominid fossils found in Africa that are older than 200,000 years old could not be in the line of descent leading to modern humans. Is the molecular evidence conclusive in proving evolution? The answer has to be "No".
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