ID craziness: Diarrhea and the appendix are signs of intelligent design

May 30, 2019 • 2:30 pm

It’s curious how adaptations that could have evolved by natural selection are nevertheless seen as evidence for Intelligent Design. Indeed, in the case of diarrhea and the appendix, as ID advocate David Klinghoffer maintains in the article below from Evolution News (click on screenshot), the evidence is not just an adaptation itself, evincing the wisdom of the creator, but supposed foresight: designing a feature in advance before it would be needed—something that natural selection couldn’t do. Unfortunately the article and associated video doesn’t show any such thing, nor does it show that ID is a more parsimonious explanation for diarrhea and the functionality of the appendix than is evolution.

Klinghoffer’s piece is about a recent book by Marcos Eberlin, a Brazilian chemist at the University of Campinas. (His Wikipedia entry states that “Eberlin is an advocate of intelligent design in Brazil, a pseudoscience on which he also lectures and he has signed the Dissent From Darwinism statement. He is a creationist also, and have said that evolution theory is a fallacy.”) 

So here are both Klinghoffer and Eberlin implying that that the Great Designer solves problems before they come up.  Klinghoffer’s blurb:

In his new book, Foresight, Dr. Eberlin develops a case for ID from the observation that so much in life and in nature appears to have been designed with a view to anticipating future problems and solving them ahead of time. Only minds can do that. Take the problem of eating adventurously and possibly consuming some bad food. The solution is diarrhea — the body’s “power wash” cycle, as he puts it. “It’s really nice,” he adds. “Diarrhea is a blessing.” You’ve probably never thought of it that way before.

But discomfort aside, the solution itself comes with a problem: it depletes the intestines of necessary microorganisms. The solution to that is the appendix, the supposedly useless, vestigial organ according to Darwinists, which in fact serves as a helpful reservoir of microorganisms.

And here’s Marcos Eberlin showing the creator’s marvelous foresight.

As for appendicitis, Eberlin claims that it’s only a problem in First World countries. I’m not sure if that’s true, and, if it is, why that’s so. Some hypothesize that in countries with less sanitation, the immune system gets used to challenges and there is thus less inflammation of this organ.  But the issue is whether the precursor to the appendix was, in net, deleterious in our ancestors, and, if so, that was the reason it shrank.

Let’s see if there’s good evidence for design here. First of all, diarrhea may well be a body’s way of flushing out toxic substances and microbes from the gut. There’s no problem with that evolving by natural selection, and this has been recognized by advocates of Darwinian medicine for a long time, as in the article below by Randolph Nesse (click on screenshot). I’m not sure that we know that diarrhea is an adaptation rather than an unevolved reaction of the gut, but at least there’s no barrier to seeing how a body’s expulsion of noxious substances could have been adaptive.

It’s also possible that the appendix serves as a reservoir of healthy gut bacteria to repopulate the intestine if it’s purged of its normal microbiome by something like diarrhea. This, too, has been suggested before, as in this paper in mbio six years ago. That paper proposes that “normal” gut bacteria are protected from purging by residing in a biofilm in the appendix, and then can reinvade the gut with healthy bacteria.

So it’s possible, and maybe even likely, that in general having an appendix is actually adaptive: you can repopulate your gut more easily with good bacteria if you have an appendix. And the “downside” of having an appendix—inflammation and death before it was possible to surgically remove it—may not have been something our ancestors faced often.

The question remains, however, whether the appendix is a vestigial organ—whether it is the remnant of a caecal pouch for digestion found in some of our relatives (some herbivores have pouches rather than an appendix). The important thing here is that vestigial organs can assume a new function. Despite that function, organs like the appendix could still be reduced remnants of a feature that once had a different (and useful) function, and thus, despite their new function, still serve as evidence for evolution. (There are, of course, many vestigial features that have no known function at all, like the muscles in human ears that can move them about or the “snake limbs” pictured below.)

It is one of the most common misconceptions about evolutionary morphology that to be vestigial, an organ cannot have a function. That’s not true: all that is required is that an organ be a reduced or degenerated remnant of a feature in an ancestor and have lost the function the presumably prompted its original evolution. It can still assume a new function.

One example: the reduced legs of snakes, which were once larger legs in their lizardlike ancestors. The males use these to stroke and stimulate the female during mating. They are clearly vestigial, as we know from both morphological and fossil evidence, but they still have a function.

Here’s a leg from the female of a ball python (Python regius), showing that the external leg is relatively short. (That’s a standard dissecting kit needle probe.) As Greg Mayer said, who provided the picture, “what you’re seeing is a claw; there’s a femur and pelvis inside.” This is clearly a vestigial feature, but it’s functional in males.

“… in snakes with vestigial limbs (e.g. Boidae), the pelvic spurs scratch or titillate the female in the vicinity of her vent.” —L. J. Vitt and J.P. Caldwell. 2009. Herpetology. 3rd ed. Elsevier, Amsterdam.

We’re not sure whether the appendix is a vestigial organ in the sense I gave above; the jury is still out. But what is absolutely clear is that there is no need to invoke the existence of a Wise Designer to explain both diarrhea and a bacteria-harboring appendix.

It’s entirely possible, for instance, that features of the gut causing diarrhea evolved as an adaptive response to toxins and bad microbes. Under many circumstances, the gut could repopulate itself from natural sources like food or contact with other individuals. But there might then be an additional advantage to those individuals who were able to sequester some of their gut bacteria on a wormlike structure of the gut: the appendix. That would be subsequent evolution by natural selection—no designer needed here, either. The whole sequence: appendix reduction—> evolution of diarrhea response—> co-option of the appendix to serve as a reservoir for “good microbiota”, can evolve by natural selection. And we don’t even need the first step should the human appendix prove not to be vestigial. Regardless of the sequence, no evolutionary “foresight” is needed.

We may not know whether the appendix evolved as a way to enhance microbe repopulation, or was the remnant of a caecal pouch that assumed this function as an adaptive byproduct. Some day we may have to revise our notion that the appendix is a vestigial organ, though I’m not ready to do that. But what is certain is that IDers like Eberlin and Klinghoffer are suffering from an extreme failure of the imagination in saying that diarrhea evinces an Intelligence On High, and that the appendix was put in place in advance to help those individuals who developed diarrhea.


h/t: Gregory

64 thoughts on “ID craziness: Diarrhea and the appendix are signs of intelligent design

  1. Well Diarrhoea was in place long before dodgy Doner Kebabs were invented ,that proves it .

        1. Plus they are always just the right length to reach the ground. Coincidence? I don’t think so…

          1. I just want to know what I did to upset God that lead to me having to have my appendix removed. Iirc, I was still quite devout back then, though not enough to believe prayer would cure me or even be an assist to the surgical team, so maybe that’s the problem right there. Or perhaps it was another case of anticipation – He knew I was going to become an atheist.

  2. And what is so Intelligent as to design something that gets infected and kills many people?

  3. Somehow I doubt that the over 2000 people worldwide who die of diarrhea each day would agree it is in anyway the “blessing” that Klinghoffer describes.

  4. “Diarrhea is a blessing”

    To never be sick would be a blessing. That humans can catch diarrhea (and even die from it) points to a very lazy and stupid designer, undistinguishable from Monod’s metaphorical tinkerer.

  5. Well, I learned something about vestigial features… any leads to where more examples of that are?

    1. WEIT of course. There’s a fair bit about it in Jerry’s book.

      I too found this article fascinating in relation to the vestigial stuff.

        1. “Exaptation”

          Yeah, that! It’s all coming back to me now.

          Now if I had the books always at my fingertips I might have known faster. Til then – library.

    2. Here are a few more–

      The palmaris longus muscle in the hand is a good one–
      It no use at all in humans (unless your life or reproductive chances depend on your ability to make your little finger press on your thumb), but for monkeys who climb in trees it’s essential. It’s disappeared in about 20% of humans, but as having one is no serious disadvantage, it’ll probably not get sorted out of the gene pool.

      1. Thank you, but I meant not just vestigial structures but vestigial structures that, like the snake limb in this post, apparently found alternative functions.

        I posted one I found – the muscles in the face.

        1. Upon the criterium of size, you can see the mammalian quadrate (incus) and articular (malleus) bones as vestigial: their size is reduced by comparison with other amniotes. Their function has also changed: from articulating the jaw to transmitting sound waves to the inner ear.

          These bones are generally not considered as vestigial organs because they serve an important function. But they are reduced in size, and a good example of unintelligent-but-working design.

          (The tensor tympani muscle that attaches to the malleus is a remnant of a larger masticatory muscle. It serves to attenuate sounds by rigidifying the tympanic membrane.)

          1. Ah yes! This also illustrates the limitation of the term “vestigial”. Is “vestigial” really that precise a technical term? Is it instead a broad generalization that is useful?

            I think those bones came up in discussion here recently? Or maybe it was something else.

  6. How do IDers explain the designers willingness to meddle in some things (like diarrhoea and the appendix) and unwillingness to meddle in things like shortsightedness?

    Because otherwise they are just cherry picking ‘the bits that fit their theory’ and ignoring the bits that don’t.

      1. They always say that in the complaints department, but I think the truth is that He is very badly organised and not really suited to the profession.

    1. Ironically (?), I just learned from the Wikipedia article that the bacterium stops producing flagellar proteins when it ramps up production of cholera toxin.

  7. If there were an intelligent designer, why not code-in hand washing as a useful trait? To Desnes point above, diarrhea seems like a half-assed (pardon the pun) fix to a problem that could have been avoided. Would an intelligent designer create the fix or solve the problem?

  8. I’ve said this before but I’m one for self pity, so here we go again. Last year I spent weeks in hospital thanks to my appendix, which ruptured terribly and led to me developing a serious case of sepsis. I’m much better now, thanks, but I feel I’ve learned in a very direct way that my body was not intelligently designed, certainly not by a caring creator!

    Besides, even if appendicitis is more common in first world countries, so what? That just means the benevolent creator was foresighted enough to provide us with a bacteria storing appendix but forgot to provide a safety valve for when much of the world developed sanitation, etc. Not much intelligence and foresight in the design in any case!

    Next time I meet an ID advocate in person (hopefully I won’t) I’ll just lift up my shirt and show them the scars I bear thanks to the likely vestigial organ which that most beneficent and talented of engineers, the Christian god, decided to foist upon me. Geez!

    1. A footnote: I’m also blessed with a hernia thanks to the surgery. And I suffer from irritable bowel syndrome. I can assure you, diarrhoea ain’t a blessing! Does this make me a living exhibit of evidence against this silly argument? I’m available for museum bookings. I’ll stand in a booth and, er, let nature take its course while showing my scars. The title shall be: ‘Praise the Lord! Intelligent design in action’.

    2. Why didn’t the intelligent designer anticipate that first world living conditions would make our currently designed appendix liable to rupture?

      Didn’t do his job? Or just doesn’t exist?

    3. How long until some Alabama (other states are available) politician tries to drum up more votes by making such intervention in Divine Will illegal, requiring doctors to return your appendix to it’s place and let God’s will have it’s way?
      Seeing the incoming round of abortion legislation, I am just waiting for retroactive God-supporting surgery to become compulsory. Doubly compulsory if you’re non-Christian, because you deserve it.

      1. ‘You will die of sepsis, you will! Praise Jesus for his inscrutable wisdom! Unless it’s me of course, my prayers have been answered and the lord tells me private surgery is okay if I ever develop appendicitis. And if any of you dare to have backstreet appendectomies you’ll be thrown in jail for life! Amen!’

      1. “Talking to god on the great white telephone” was the euphemism of choice for contenders for the Creag Meagaidh Bucket.

  9. I thought that the appendix was promoted up from vestigial organ to a minor non-vestigial lymphoid organ with other uses. It is a reservoir for gut immune cells that reside within lymphatic tissue within it. It also harbors gut bacteria, and some of these bacteria produce vitamin K (whatever that is). Depending on the species, the appendix can be very large (as in herbivores), or very small (as in carnivores). But in all cases it is not really vestigial, but rather it is what it is needed to be.

    1. The question is whether it was a caecum that got reduced because we no longer need such a pouch, and was coopted for other things. If this is the case it would still be considered vestigial: a remnant of a caecum (digestive pouch).

  10. Then gawd must have really been on a roll when it created Norovirus, after all, it would take a super genius to choose to design something that had me sitting on the crapper with explosive diarrhea shooting out one end while projectile vomiting into the bath tub from out the other end!

    1. If people hadn’t designed bathrooms with the bath and shower only a few feet apart, then God (praise be upon her) would have had no need to invent the norovirus. It’s all our fault!

  11. Diarrhea is very HARD on our body chemistry. Highly dehydrating. Severe bouts can kill infants and the elderly. Part of the designer’s loving plan?

  12. God: “I know! I’m going to design this critter so that it can’t digest food on it’s own, it has to use symbiotic microorganisms. But I’m going to design those symbiotes so that there’s lots of food-type stuff that will kill them. This is going to be a problem for my favored organism, so I’m going to give it a little pocket in it’s digestive tract where extra symbiotes can live, unaffected by anything that poisons the vast majority of them”

    Satan: “Uh…boss…why not just design them to digest whatever they can eat?”

    God: “To hell with you!”

  13. Marcos Eberlin: A Design Perspective on Diarrhea

    “Intelligent design is the intellectual equivalent of diarrhea.


    Oh. Well, that wasn’t much of a paper.

  14. Teaching ID in US public schools is considered a violation of the Establishment Clause of the First Amendment.

    But is ID taught in other schools in the US?

    If so, is ID teaching in schools on the rise?

    1. I think (from a trans-Pondian viewpoint, the answers are Yes, Yes, and Yes. The archive of posts and a million-plus comments is there to explore. And there will be another post on the topic along soon – a safe prediction!

  15. So next time I have a case of the trots I must remember that. I can sit there having the squitters and say “Thank you, Jesus. Thank you, Lord!”


    1. I think you are all missing the point if that Eve woman had only kept her theifing hands to herself ,we would all have perfect minds and bodies .
      Or if they have done told on that talking snake to the big sky daddy .

  16. By the logic of this guy, god also created feet because he knew we’d need to walk, eyes because he knew we’d need to see, ears because he knew we’d need to hear, etc. But he also created a liver because we’d need to filter out toxins, so why create all those toxins? He knew we’d need a digestive system for a complex process of extracting nutrition from the food he gave us and creating waste from the parts we don’t need. Why didn’t he give us a simpler system? I mean, so many things go wrong with all the systems we have, so we die from those problems.

    Oh well. I guess it’s all just part of “god’s plan.”

  17. Seems far more likely that it is the bacteria/viruses that have done most of the evolving, coming up with a means of triggering just the right level of electrolyte imbalance to trigger a discharge of intestinal contents greatly in excess of ordinary, allowing the pathogens to spread more widely, while at the same time not always being fatal to the host.

    Of course different gut pathogens trigger different levels of diarrhea, and I don’t know enough specifics on infectious disease to cite examples (altho someone above mentioned cholera) but I can at least note that diarrhea is often fatal in third-world countries, and so how does that fit into your scenario, Klinghoffer?

    I think attenuation of pathogenicity over time is a well-known phenomenon, but I recall in particular that someone – I think it was George Klein – has written on it.

  18. I think someone from Brazil really needs a rip-roaring week of profuse and uncontrollable diarrhoea to really appreciate the blessing that it is.

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