Creation vs. Evolution
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Is the molecular evidence conclusive?
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.
Another molecular comparison that is made uses cytochrome c., a protein. "A standard reference table shows the percent sequence divergence between the cytochrome c. of a particular bacterium and a wide variety of more complex organisms, including mammals, birds, reptiles, amphibians, fish, insects and angiosperms (plants). The sequence divergence from the bacterial form ranges from 64 percent (rabbit, turtle, penguin, carp, screw worm,) to 69 (sunflower). Judged by cytochrome c. comparisons, sesame plants and silkworms are just about as different from bacteria as humans are." (Johnson, 1991)
Mitochondrial DNA has been analyzed in the study of human descent. This analysis shows that all contemporary humans are 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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