Steven Novella, a neurologist and noted “skeptic” at Yale University School of Medicine, has commented on a recent Harvard University experiment for visualizing bacterial adaptation to antibiotics. In doing so, he argues with Michael Behe whose take on the subject was noted at Evolution News. Here is why Dr. Novella is wrong.
The Harvard researchers constructed a giant petri dish with spatially varying antibiotics to watch how bacteria adapt over time and space (the researchers came up with a great name for the experiment: The microbial evolution and growth arena [MEGA]-plate). And adapt they did. Those adaptations were instantly claimed as an example of evolution in action. The researchers wrote that the “MEGA-plate provides a versatile platform for studying microbial adaption and directly visualizing evolutionary dynamics” (emphasis added). And the press release informed the public that the experiment provided “A powerful, unvarnished visualization of bacterial movement, death, and survival; evolution at work, visible to the naked eye.” Likewise, Novella called it “a nice demonstration of evolution at work in a limited context.” There’s only one problem: The experiment did not demonstrate evolution, it falsified evolution.
First off, Novella deserves some credit for acknowledging at least some limitations in the experiment’s results:
Of course, this one piece of evidence does not “prove” something as complex and far ranging as the evolution of life on Earth.
Novella also deserves credit for acknowledging that evolutionary change that requires a few mutations, rather than merely one, is a big problem. Novella has solutions that he believes resolve this problem, but at least he acknowledges what too often is conveniently ignored.
What Novella does not acknowledge, however, is that bacteria adaptation research, over several decades now, has clearly shown non-evolutionary change. For instance, bacterial adaptation has often been found to be rapid, and sensitive to the environmental challenge. In other words, when we look at the details, we do not find the evolutionary model of random variation slowly bringing about change, but rather environmentally directed or influenced variation.
That is not evolution. And indeed, the Harvard experiment demonstrated, again, very rapid adaptation. In just ten days the bacteria adapted to high doses of lethal antibiotic. As one of the researchers commented, “This is a stunning demonstration of how quickly microbes evolve.”
True, it is “stunning,” but “evolve” is not the correct term. The microbes adapted.
The ability of organisms to adapt rapidly falls under the category of epigenetics, a term that encompasses a range of sophisticated mechanisms which promote adaptation which is sensitive to the environment. Given our knowledge of bacterial epigenetics, and how fast the bacteria responded in the Harvard experiment, it certainly is reasonable to think that epigenetics, of some sort, may have been at work.
Such epigenetic change is not a new facet of evolution, it contradicts evolution. Not only would such complex adaptation mechanisms be difficult to evolve via random mutations, they wouldn’t provide fitness improvement, and so would not be selected for, even if they did somehow arise from mutations.
Epigenetic mechanisms respond to future, unforeseen conditions. Their very existence contradicts evolution. So the Harvard experiment, rather than demonstrating evolution in action, is probably yet another example of epigenetic-based adaptation. If so, it would contradict evolution.
Another problem, one that Michael Behe points out, is that it appears that most of the mutations that occurred in the experiment served to shutdown genes. In other words, the mutations broke things, they did not build things. This is another way to see that this does not fit the evolutionary model. It’s devolution, not evolution. Novella begs to differ, and says Behe has made a big mistake:
Behe is wrong because there is no such thing as “devolution.” Evolution is simply heritable change, any change, and that change can create more complexity or more simplicity. Further, altering a protein does not “degrade” it — that notion is based on the false premise that there is a “correct” sequence of amino acids in any particular protein. Evolution just makes proteins different. Proteins perform “better” or “worse” only in so much that they contribute to the survival and reproduction of the individual. If it is better for the survival of the organism for an enzyme to be slower, then the slower enzyme is better for that organism.
First, Novella ignores the fact that many of the mutations introduced stop codons, and so did not merely slow an enzyme but rather shut it down altogether.
Secondly, it is not Behe here who is making the mistake, it is Novella. He says “Evolution is simply heritable change…” But this is an equivocation.
On the one hand, evolutionists want to say that shutting down or slowing a gene is “evolution,” but on the other hand, they say that a fish turning into a giraffe is “evolution.”
Unfortunately evolutionists routinely make this equivocation. This is because they don’t think of it as an equivocation. In their adherence and promotion of the theory, the distinction is lost on them. All change just smears together in one big long process called evolution. You can see other examples of this here and here.
So the comments, press releases, and articles send a misleading message. Readers are told that the researchers have seen “evolution in action.” The message is clear: This is evolution, the evolution. But it isn’t. There is nothing in these findings that show us how a fish turns into a giraffe.
As I mentioned, Novella also believes that evolution coming up with designs requiring multiple mutations is not a problem. His reasoning is that while this would be a problem if most mutations were harmful, they aren’t. Most mutations are neutral, so evolutionary drift can introduce the many needed mutations, and once the set of required mutations are in place, then you have the new design.
This is a profound misunderstanding of the problem evolution faces. You can’t evolve a protein, for example, with drift. That most mutations are neutral does not suddenly resolve the curse of dimensionality and resolve this astronomical search problem. There just is no free lunch.
Similarly, Novella makes yet another profound mistake involving what he calls “the lottery fallacy.”
The first is basically the lottery fallacy – considering the odds of John Smith winning the lottery by chance alone and concluding it could not have happened by chance. Rather, you should consider the odds that anyone would win the lottery. This is actually pretty good. Behe looks at life on Earth and asks — what are the odds that this specific pathway or protein or whatever evolved by chance alone. He is failing to consider that there may have been billions of possible solutions or pathways down which that creature’s ancestors could have evolved. Species that failed to adapt either migrated to an environment in which they could survive, or they went extinct. In other words, Behe should not be asking what the odds are that this bit of complexity evolved, but rather what are the odds that any complexity evolved. It is difficult to know the number of potential complexities that never evolved — that number may dwarf the odds of any one bit evolving. Right there Behe’s entire premise is demolished…
This is a terribly flawed argument for several reasons. First, life needs proteins. All life that we know of needs proteins. Thousands of proteins.
Yet proteins are far beyond evolution’s reach. It is true, per Novella’s point, that there are a whole lot of ways to make a given protein. There are many, many different amino acid sequences that give you a globin. But “many, many” is like a grain of sand compared to the astronomical amino acid sequence search space. Again, there is no free lunch.
But Novella goes further than this, which brings us to the second flaw. Novella is not merely arguing there are many different ways to construct life as we know it. He is pointing out that there are, or at least there could be, a whole bunch of different ways to make life in the first place.
If you take them all together, you could have a pretty big set of possibilities. Perhaps it is astronomical. So what we got in this world — the life forms we observe — are not point designs in an otherwise lifeless design space. Rather, the design space could be chock full of life forms. And hence, the evolution of life becomes likely, and “Right there Behe’s entire premise is demolished.”
What Novella is arguing for here is unobservable. He is going far beyond science, into an imaginary philosophical world of maybes.
Not only is Novella clearly appealing to the unobservable, but even that doesn’t work. At least for any common sense approach. There is no question that the design space is full of useless blobs of chemicals that do nothing. A speculative claim? No, that is what this thing called science has made abundantly clear to us. Even the simple case of a single protein reveals as much. Only a relatively few mutations to most proteins rob them of their function. Protein function is known to dramatically reduce as different amino acids are swapped in.
Of course this is all obvious to anyone who understands how things work. Sure, Novella may be right that there are other, unknown, solutions to life. But that isn’t suddenly going to resolve evolution’s astronomical search problem. The problem was never contingent on the life we observe being the only possible life forms possible
Professor Novella calls himself a skeptic. In fact, he is exactly the opposite.
Cross-posted at Darwin’s God.