…because he’s sure as heck doing his best to cause it damage with his latest antievolution “broadsides,” even to the point where it needs the loving ministrations of a neurosurgeon! His latest screeds produce in me a nearly irresistible urge to pound my head against the nearest hard surface to make the psychic pain stop. He’s placing me in danger of real, physical pain, from epidural hematoma (in fact, I wonder if I’m in the middle of a lucid interval right now) to subdural hematoma to cerebral contusions.
First of all, regular readers may have noted that I haven’t yet responded to the latest broadside against me launched by the Discovery Institute’s new resident medical “expert,” creationist neurosurgeon extraordinaire Dr. Michael Egnor. There’s a reason for that, and it’s quite simple. As I’ve said before, I don’t want this blog to become “all Egnor, all the time.” There is such a thing as too much of a good thing (having a good laugh at the expense of Dr. Egnor for his ever increasingly incorrect and even mutually contradictory assertions about evolution–or “Darwinism,” as he insists and calling it with a sneer), and even my (hopefully) amusing deconstructions of his silliness run the risk of being tiresome after a while. Second, I am somewhat sympathetic to the complaint that I’ve occasionally heard voiced that Dr. Egnor is just so ridiculously–nay, flamboyantly–wrong about evolution that he’s not worth the effort that it takes to debunk him. Afarensis has even gone so far as to speculate that Dr. Egnor and Dembski’s attack “intelligent design” mouse DaveScot are actually one and the same person. It’s a tempting thought, but I don’t think so after having heard Dr. Egnor on some of his podcasts. Finally, I rather suspect that Dr. Egnor has figured out that “answering” criticisms leveled against him is a good way to get a lot of bloggers interested in evolution to link to the pathetic Discovery Institute blog, thus driving its traffic to many times its usual level. So far, it’s working. However, even at the risk of doing that, Dr. Egnor did directly address me directly with his latest mangling of logic claiming that evolution “is of no use” to understanding cancer. It’s almost as though he’s asking for yet another dose of Respectful Insolence™.
Actually, there’s no “almost” about it.
Consequently, in spite of the fact that I’ve been trying to ration my responses to Dr. Egnor and even was tempted to leave his latest volley alone, in which he criticizes my discussions of how evolutionary theory is increasingly being used in understanding how cancer develops and grows, specifically my year-old discussion of the use of the Shannon index to predict in which patients Barrett’s esophagus will develop into frank cancer as opposed to never progressing, I feel obliged to grant Dr. Egnor his wish and give him a taste of what he apparently craves. Oddly enough, though he left alone my more recent discussions of how evolutionary theory is being increasingly used not only to study tumor cell populations but how evolution helps us to understand why various alleles predisposing to cancer do not disappear from the human population. In any case, his response to my discussion of evolutionary theory and cancer left me truly, truly puzzled. Once again, in his eagerness to “rebut” me, he’s apparently forgotten what he’s written before and, once again, amusingly appearing to rebut one of his own earlier arguments.
Here’s what Dr. Egnor said a while back:
This is the age of pseudo-Darwinism. Pseudo-Darwinism is the synthesis of Darwin’s theory and ‘anything you can think of.’ We have the synthesis of Darwin’s theory and the discovery of the genetic code. We have the synthesis of Darwin’s theory and the biotech industry (transgenic organisms are designed and bred to produce human insulin–thanks to Darwin!). We have the synthesis of Darwin’s theory and cancer research. We have the synthesis of Darwin’s theory and psychology (evolutionary psychology), Darwin’s theory and sociology (sociobiology), Darwin’s theory and culture (memes), Darwin’s theory and literature (literary Darwinism), Darwin’s theory and cosmology (multiverses), and Darwin’s theory and, well, everything (Dennett’s universal acid). None of these have anything to do with Darwin’s theory–the theory that all natural biological complexity arose by non-teleological variation and natural selection.
Got it? According to Dr. Egnor, applying “Darwinism” to the study of cancer is “pseudo-Darwinism.” However, in his eagerness to attack me, he seems to have changed his mind:
Yet Darwin’s theory is related to cancer, in a very important way. Darwin asserted that all natural integrated biological complexity arose by random variation and natural selection. Cancer does seem to grow in accordance with Darwin’s mechanism. The “variation” of cancer cells seems random, and cancer cells are certainly “naturally selected,” in the tautological sense that replicating cells eventually outnumber non-replicating cells. Darwin’s theory can be applied to cancer, trivially.
The converse is more interesting: cancer can be applied to Darwin’s theory. Cancer is a Darwinian process, unlike the examples of experimental molecular design and artificial selection that Darwinists often cite inappropriately as applications of Darwin’s theory. Darwinists claim that “random variation and natural selection” is a model of cancer growth, and they’re right.
Come on, can’t Dr. Egnor even keep his misinformation straight? In the first quote, he rails against the application of “Darwinism” to the study of cancer as “pseudo-Darwinism” but now turns right around and admits that, yes, cancer is indeed a Darwinian process. Indeed, shockingly, he gets one part mostly right when he points out that random mutation leads to phenotypic changes that allow uncontrolled proliferation, the ability to evade the immune system, invasion, angiogenesis, and ultimately metastasis, and indeed the cells in a tumor mass are genetically heterogeneous. Among this heterogeneous population of cells, the selective pressures of the immune system, hypoxia (requiring angiogenesis to overcome), and the normal signals the body is always producing to keep cells from proliferating when they are not supposed to proliferate eliminate tumor cells unable to do these things and lead to the preferential proliferation of more malignant clones.
A better description of natural selection in action on a cellular level, I have a hard time imagining!
I have to admit that I remain very confused. Think about it. If, as Dr. Egnor admits, cancer is indeed a “Darwinian” process, then how on earth can he say that understanding evolution (or, in Egnor-speak, “Darwinism”) is useless for understanding cancer and designing more effective therapies? Does anyone see the logical fallacy there? Basically, Dr. Egnor’s just admitted that the evolution of a cancer from random genetic mutation is “Darwinian” but then says that “Darwinism” tells us nothing about cancer. True, he uses the same lame and fallacious claim that natural selection is a “tautology” in this context, just as he did when arrogantly dismissing the role of evolution and selection in the evolution of bacterial resistance to antibiotics. It’s such a lame argument that it was debunked long ago, one deconstruction being featured on TalkOrigins.org. He also uses the same old straw man that Darwin said that “all” complexity arises from random variation and natural selection, when in fact Darwin said that he thought natural selection was the main (but not the only) force responsible.
Dr. Egnor’s understanding of chemotherapy and radiation theory could use some fine-tuning, as well:
Chemotherapy and radiation therapy are designed with the view that the tumor is a heterogeneous collection of cells. That’s why radiation therapy is usually delivered in fractionated doses over a period of time, to destroy cells that are cycling through intervals of sensitivity and insensitivity. Is the view that pre-cancerous lesions are “thousands of cells” and not just a “single organism” really novel to Orac, who is a surgical oncologist? Of course not.
First off, I never said that treating a tumor as thousands of clones of cells (not cells, Dr. Egnor) is something novel. I merely pointed out that that’s how the researchers did the study that I described and applied evolution and the Shannon index to the development of esophageal cancer from Barrett’s esophagus. Second off, radiation therapy is not given in fractionated doses to destroy tumor cells that are cycling through “periods of sensitivity and insensitivity.” Rather, it is given that way to save as many surrounding normal cells as possible from the radiation. The basis of this effect is that tumor cells are generally defective in DNA repair and cannot repair damage from radiation to their DNA as efficiently as normal cells. By giving the normal cells a “rest” between smaller fractions (doses) of radiation, we allow the normal cells to recover and repair their DNA, while the tumor cells are not as good at doing that and thus continue to accumulate DNA damage with each new fraction. Thus, giving radiation in multiple fractions, usually separated by a day, maximizes the differential toxicity of radiation to the tumor cells compared to the normal cells, sparing as many normal cells as possible. If radiation therapists just blasted away with a single fraction, the “collateral damage” to surrounding normal tissue would be severe. (It’s known as a burn.) Radiation oncologists sometimes do that when fast tumor shrinkage is urgently needed (for example, in the case of a tumor compressing the spinal cord), but usually they do not. As for chemotherapy, it is indeed true that chemotherapy regimens are in some cases timed to provide better synchronization with the cell cycle, but in reality such strategies tend not to work that well, mainly because the cells in a tumor replicate asynchronously; i.e., they’re randomly distributed between the phases of the cell cycle, and it’s quite difficult to synchronize them. In reality, though, the main reason for multi-drug combinations aimed at different molecular targets is that tumors very rapidly develop resistance to single-drug regimens. How does Dr. Egnor think tumor cells accomplish this? His “tautology” of selection does it quite well, selecting for resistant clones, which exist because of the high mutation rates in tumors. Dr. Egnor should know the mechanisms by which radiation and chemotherapy kill tumors and the rationale behind why they are administered the way they are.
It’s amusing indeed that Dr. Egnor successfully refutes his own argument. Now that I think about it, I didn’t even have to make reference to his previous posts. Dr. Egnor refutes himself quite well all in the same post. But, sadly, he wasn’t done, yet, alas. Just when I think that Dr. Egnor can’t elevate the stupid any higher, he straps on rockets and and hits the “lift off” button. Mike pointed me to this new gem by Dr. Egnor, in which he attempts to refute neurologist and skeptic Dr. Steve Novella’s discussion of why a previous tract by Egnor was wrong:
Dr. Novella is missing a much better example of random mutation and natural selection that’s not metaphorical at all. Cancer is a test of Darwin’s theory. Cancer is real biological evolution by random mutation and natural selection, writ fast. There’s no reason to invoke encyclopedia typos or tractor engines in order to understand what “chance and necessity” can do to a living system. Brain tumors are perfect little Novellian “two-cycle engines” nestled inside the skull, “random mutations” coming out the ears, and “natural selection” like there’s no tomorrow (excuse the metaphors). Brain tumors are constantly generating new biological variation, and they are avatars of natural selection. They provide a tremendous spectrum of variation, from “variation jet-engines” like malignant glioblastoma multiforme to “variation tortoises” like benign pilocytic astrocytomas. Cancer wards are full of patients brimming with “two-stroke engines” of evolutionary change.
Besides noting that, once again Dr. Egnor refutes his previous assertions that evolution is “useless” for studying cancer. He even characterizes tumors as “‘random mutations’ coming out the ears, and ‘natural selection’ like there’s no tomorrow, “avatars of natural selection”!
Thanks again, Dr. Egnor.
Here’s where he dives more deeply into the stupid after describing himself, quite appropriately, as “just a rube” (certainly with regard to evolution he is):
The best real biological test of “shuffling around information, duplicating, and altering the information” is cancer. According to Dr. Novella’s reasoning, brain tumors ought to be generating quite a bit of “meaningful and even useful new information.” Better neuroanatomy and better neurophysiology ought to be popping up “easily.” Better frontal lobes and cognition, from cancer. Better temporal lobes and memory, from cancer. Better cerebellums and coordination, from cancer. If random mutations and natural selection–Dr. Novella’s “two stroke engine”–is the source of all functional integrated biological complexity, brain tumors ought to help our brains evolve in some way.
Perhaps Dr. Novella has data that show real evolutionary improvements in the brain caused by brain tumors. If he has, he should show us.
I have to admit that this is a creationist argument that I had never heard before–after I wiped my drink off my computer screen, that is. The reason, I suspect, is that even Kent Hovind on a weekend bender wouldn’t make an argument this monumentally bad. It’s the Mt. Everest of dumb. Of course, Mike and Mark completely shred this mind-bogglingly idiotic argument quite handily, but I’ll elaborate somewhat. As Mike points out, Dr. Egnor is completely ignoring the distinction of what selection is working on in this example, specifically whether Darwinian processes are working on the organism as a whole or on the tumor cells. Evolution only works on heritable variation, leading to an increase in the frequency of alleles in subsequent generations that increase fitness and a decrease in those leading to a decrease in fitness. The only way for evolution to “improve the brain” (whatever that means) is through many generations of offspring under selective pressure. However, at the level of the tumor cell, Dr. Egnor again unknowingly presents a great explanation why tumors represent a Darwinian process, all the while denying that they do. Again, random mutations in the tumors lead to high degrees of genetic variability, and selective pressures act on that variability so that each generation of tumor cell progeny develop a greater degree of “fitness” for doing what tumor cells do, namely growing, invading, tricking the body to supply them with blood and nutrients, and metastazing. My only quibble with Mike is that there’s no “sometimes” about this process. It happens in virtually all tumors, beginning right after very first mutations lead to loss of growth control, as the tumor microenvironment selects for clones that proliferate, invade, induce angiogenesis, and metastasize, etc.. These same sorts of mutations are naturally selected for after a a cell is transformed into a malignant cell, and when a tumor is treated with chemotherapy, resistance is artificially selected for.
You know, I used to joke about putting a paper bag over my head in embarrassment at Dr. Egnor’s antics. I was kidding then. Maybe I shouldn’t have been. In fact, given that Dr. Egnor has seemingly settled in to become a permanent fixture and a permanent embarrassment to the profession of surgeon, maybe it’s not too late to get the more permanent solution that I had once mentioned, namely a Doctor Doom-style metal mask. In the meantime, while having the Doom mask forged by Tibetan monks, I could wear a hockey mask.
I could borrow it from EneMan.
ADDENDUM: Dr. Novella adds his two cents here.
Most amusingly of all, Dr. Egnor adds some more rockets to the stupid, enough to blast it to Mars, here, where he basically claims that all science is based on the Judeo-Christian “design inference.” He even has the chutzpah to mention Galileo as evidence. (As a Catholic, doesn’t he remember that little thing about the Catholic Church putting Galileo under house arrest and forcing him to recant?) He also seems to forget that the origins of science lie before Christianity, namely among those pagan Greeks and Egyptians, among others.