Another Darwinian Assumption Overturned: Results Too Radical
Evolutionists are stunned at a study in comparative genomics performed by University of Chicago researchers that overturns a common belief about natural selection. EurekAlert summarizes the finding: “The new data show that if more mutations show up at a gene, that gene tends to accept a higher percentage of those mutations.” This means that mutations accepted into a genome are not strictly a function of natural selection, but of mutation rate.
Mutations accepted into a gene can be synonymous or non-synonymous. Synonymous mutations (Ks) swap an amino acid with a similar one, such that the protein can still function. Non-synonymous mutations (Ka) change the shape of the protein and thereby can be acted on by natural selection. Scientists have assumed that the percentage of non-synonymous mutations accepted during evolution remains constant. Bruce Lahn, author of the paper in Trends in Genetics, commented on the assumption: “This theory has been the workhorse of molecular evolution. Thousands of scientific papers have been published based directly or indirectly on this notion.” The new study shows, instead, that “the faster the speed of new mutations, the greater the percentage of those mutations accepted.”
Several statements in the press release make this finding sound revolutionary:
- “We’ve discovered a striking phenomenon that challenges a paradigm of molecular evolution that has been around for several decades,” said lead author Bruce Lahn, Ph.D., assistant professor of genetics at the University of Chicago and Howard Hughes Medical Institute investigator. “As such, it may cause a significant shift in the field.”
- Lahn cannot explain the mechanism of his findings and expects many will question this novel finding. “It’s too radical,” he said. “People just don’t want to believe it, but the data are there.”
- “Lahn and his associates have found a most striking result, one that is totally unexpected,” said geneticist James Crow, professor emeritus of genetics and zoology at the University of Wisconsin-Madison.
- Sudhir Kumar, an associate professor of molecular evolution at Arizona State University, agreed. “It goes against strict theory, but evolutionary biologists know that nothing’s clean cut. There’s always distortion because we’re looking at longtime history.
(Emphasis added in all quotes.) What this means is up in the air. James Crow ended with a look to the future: “I hope that further work will provide an explanation of what now is a major puzzle.”
What if a flood of mutations struck in a short period? Could it account for a wide range of mutational changes in the relatively recent past? How would they know? This result appears to undercut any remaining trust in the molecular clock, a device that was broken anyway (see 08/24/2004 entry).
Kumar hit the nail on the head: evolutionary theory is never clean cut, and is always subject to distortion. If evolutionists are trying to look at longtime history, good luck – because history cannot be put into a test tube. Trying to decipher history from present observations of genes and proteins is messy business, subject to numerous assumptions that can be overthrown, such as this one. Kumar said “The novelty of this work is that he [Lahn] used a large amount of data.” What does this tell you about the evolutionary assumptions built on far less data?
The Darwinists are certainly not throwing in the towel over this latest genetic earthquake. It just illustrates that assumptions in science, trusted for decades, yielding thousands of scientific papers, can be flat wrong.