Paper Provides More Evidence that Mutations Aren’t Random
Earlier this year we covered a paper in Nature which found that mutations in the Arabidopsis genome were not occurring randomly. As that paper noted, “The random occurrence of mutations with respect to their consequences is an axiom upon which much of biology and evolutionary theory rests.” Yet the findings of the paper overturned these basic principles of modern evolutionary biology. Now another paper, this one published in Genome Research by biologists from Israel and Ghana, reports similar findings about the non-random nature of mutations.
Mutation in Response to Need
A news release from the University of Haifa pulls no punches about the implications: “Groundbreaking study uncovers first evidence of long-term directionality in the origination of human mutation, fundamentally challenging Neo-Darwinism.” They report:
A new study by a team of researchers from Israel and Ghana has brought the first evidence of nonrandom mutation in human genes, challenging a core assumption at the heart of evolutionary theory by showing a long-term directional mutational response to environmental pressure. Using a novel method, researchers led by Professor Adi Livnat from the University of Haifa showed that the rate of generation of the HbS mutation, which protects against malaria, is higher in people from Africa, where malaria is endemic, than in people from Europe, where it is not. “For over a century, the leading theory of evolution has been based on random mutations. The results show that the HbS mutation is not generated at random but instead originates preferentially in the gene and in the population where it is of adaptive significance,” said Prof. Livnat. Unlike other findings on mutation origination, this mutation-specific response to a specific environmental pressure cannot be explained by traditional theories. “We hypothesize that evolution is influenced by two sources of information: external information that is natural selection, and internal information that is accumulated in the genome through the generations and impacts the origination of mutations,” said Livnat. [Emphasis added.]
If they are correct, then some groups of humans have evolved the ability to produce necessary mutations to lead to certain beneficial adaptations more frequently than those humans who lived in environments where those adaptations wouldn’t have been helpful. This suggests that mutations do not necessarily happen without regard to the needs of organisms — which, as they put it, “fundamentally challeng[es] Neo-Darwinism.”
“From the Hawk’s Sharp Eye to the Human Cardiovascular System”
Or does it? After all, they seem to propose that the ability to preferentially produce favorable mutations itself is an adaptation that arose by (presumably) unguided evolutionary mechanisms:
Ever since Darwin we have known that life arose by evolution. But how, exactly, does evolution — in all its grandeur, mystery and complexity — happen? For the past century scientists have assumed that mutations occur by accident to the genome and that natural selection, or the survival of the fittest, favors beneficial accidents. The accumulation of these presumed genetic accidents under natural selection over the millennia leads in turn to adaptations, from the hawk’s sharp eye to the human cardiovascular system. … “Mutations defy traditional thinking. The results suggest that complex information that is accumulated in the genome through the generations impacts mutation, and therefore mutation-specific origination rates can respond in the long-term to specific environmental pressures,” said Prof. Livnat.
But how did this preferential tendency to produce useful mutations itself arise? Most materialists will say that it arose by chance mutations that became fixed in populations because they were beneficial to organisms. So you’re back to a neo-Darwinian view of mutations after all — random mutations produce beneficial traits even if neo-Darwinian mechanisms sometimes produce non-random biases towards beneficial mutations.
A Vague Lamarckian Fashion
But is that the only explanation for the origin of such mutational biases? Could not intelligent design also explain the presence of mutational spectra that spike where there may be a benefit for an organism? Would that not be a good design strategy to build into living organisms? The technical paper ignores such possibilities — preferring to say that “epigenetic” mechanisms exist which allow these preferences to evolve in a vague long-term Lamarckian fashion. From the news release:
While widely held in the scientific community, this view has always left open fundamental questions, such as the problem of complexity. Can the sequential accumulation of small random changes, each beneficial on its own, lead within the timespan available to the evolution of such astonishingly complex and impressive adaptations as we see around us in nature, such as eyes, brains or wings, where complementary parts interweave into a complex whole? However, the only alternative at the fundamental level conceived of up until now consisted of variants of Lamarckism — the idea that organisms can somehow respond directly to their immediate environments with beneficial genetic change. Since Lamarckism has not worked in general, the notion of random mutation remained the prevailing view. … Previous studies, motivated by Lamarckism, only tested for an immediate mutational response to environmental pressures. “Mutations may be generated nonrandomly in evolution after all, but not in the way previously conceived. We must study the internal information and how it affects mutation, as it opens the door to evolution being a far bigger process than previously conceived,” Livnat concluded.
These researchers have done innovative research to investigate rates of “de novo mutations — mutations that arise ‘out of the blue’ in offspring without being inherited from either parent.” Their findings are extremely important: mutations aren’t random and may occur in patterns that are designed to benefit an organism. How did this arise? Epigenetics may be the direct mechanism, but how did those epigenetic mechanisms arise? Their origin has obvious design implications. But if your only alternative to neo-Darwinism is Lamarckism or some hazy materialistic model of evolution, then you are going to miss the viable possibility of intelligent design.
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