44 thoughts on “The Appendix”

  1. Beware various teleological fallacies. You can talk about things that evolved in humans which don’t have a “purpose”, but still have an evolutionary explanation. For example, see this paper “Evolutionary Genetics of Coronary Heart Disease” http://circ.ahajournals.org/content/119/3/459 We would not be hubristic to say that heart disease has no “purpose” in the sense that the authors of the appendix paper are using the word, and we can still discuss the evolutionary pathway that led to heart disease.

    1. What on earth are you talking about? To say that the appendix has a function that we don’t know about isn’t a teleological fallacy.

    1. Sure you did.

      Here’s the definition:
      tel·e·ol·o·gy
      nounPHILOSOPHY
      the explanation of phenomena by the purpose they serve rather than by postulated causes.

      I don’t see any other way to understand your opinion that it is hubristic to think that “something evolved in humans has no purpose”, except in terms of teleology.

  3. How about “purpose” as in “evolved to make the organism more fit in its environment”? There was no deep philosophical point to be made, despite your straining for one.

    1. I am straining to address only the very point you are making, nothing deeper. I have no hidden agenda.

      My claim: All the mainstream variants of the theory of evolution suggest that the human body will have aspects which do not have any purpose, if “purpose” is defined as you are defining it: “evolved to make the organism more fit in its environment”.

          2. I have this crazy idea that an organ that can go spectacularly fatally wrong, sometimes killing prior to generating offspring, must have some beneficial purpose, or there would have been evolutionary pressure to get rid of it.

  4. Teleology implies the purpose of something is inherent at the beginning. The purpose of the acorn is the oak tree.

    Rand is using the definition of purpose to imply function, there’s no “teleology” involved.

    1. A different teleological fallacy is to suggest, regardless of the past that something *currently* has a purpose when it doesn’t.

      Yet another teleological fallacy is to suggest, regardless of time, that something has or had a “function” when it didn’t or doesn’t.

      The appendix might very well have the function of serving a reservoir for beneficial gut bacteria, but I believe all popular theories of evolution suggest that there will be aspects of the human body which do not serve any function. For example, I have a small brown mole on my forearm. Maybe it serves a function, but I do not think it would be hubristic to believe that it does not. I believe that it would be a teleological fallacy to say that because the mole on my forearm is a product of human evolution, it has a function, and I think that’s what Rand is claiming for the general case of things that evolve in the human body.

        1. For example, I have a small brown mole on my forearm

          A small brown mole likely is the result of evolution — and it may also have a “purpose” (as defined earlier) — and yet in point of fact that purpose may have nothing to do with the welfare or “purpose” of the body as a whole.

          This is because evolution also occurs within the body — not just between “bodies” (individuals) at the species level — in the context of which, the cells that make up such entities as “brown moles” constitute a lineage which, if not fully piratical, has at least partially thrown off the yoke of the body as a whole.

          You see, cancer is an evolutionary phenomenon.

          It’s precisely because cancer (that is, cells developing the ability to escape from the body’s pervasive controls on growth — which is to say, in effect raising up the Jolly Roger, declaring independence, and embarking on an independent life of rapine and mayhem — until the host dies) has the force of evolution behind it — pushing it on relentlessly, like a force of nature, which it is — that this multifaceted disease is so tough a nut to crack.

          This knowledge about the nature of cancer is not exactly new — it’s a decade or two old — but it’s still not well known to most folk.

          A review article in the scientific journal Nature a few years back on the subject of the genomics of cancer — the different kinds of DNA alterations (oftentimes wholesale) that the process of becoming cancerous accomplishes — puts the matter succinctly:

          Cancer is an evolutionary process

          All cancers are thought to share a common pathogenesis. Each is the outcome of a process of Darwinian evolution occurring among cell populations within the microenvironments provided by the tissues of a multicellular organism. Analogous to Darwinian evolution occurring in the origins of species, cancer development is based on two constituent processes, the continuous acquisition of heritable genetic variation in individual cells by more-or-less random mutation and natural selection acting on the resultant phenotypic diversity. The selection may weed out cells that have acquired deleterious mutations or it may foster cells carrying alterations that confer the capability to proliferate and survive more effectively than their neighbours. Within an adult human there are probably thousands of minor winners of this ongoing competition, most of which have limited abnormal growth potential and are invisible or manifest as common benign growths such as skin moles. Occasionally, however, a single cell acquires a set of sufficiently advantageous mutations that allows it to proliferate autonomously, invade tissues and metastasize.

          (/endQuote)

          Mutation + natural selection IS evolution.

          Nature 458, 719-724 (9 April 2009) | doi:10.1038/nature07943;
          http://www.nature.com/nature/journal/v458/n7239/full/nature07943.html

      2. Francis Bacon et al. removed teleology from scientific thinking. The paradigm used in medicine was that all body parts had a purpose. If it didn’t, then they didn’t know why it was used. Purpose was function.

        To suddenly bring up teleology means that you are arguing a completely different paradigm with current science. You are redefining 400 years of scientific methodology. You are bringing Aristotelianism into science.

        Why you are doing this makes no sense.

      1. Ok, so now look at your original post. You spoke of the “hubris of people who think that, just because they can’t figure it out, something evolved in humans has no purpose.”

        You didn’t talk about evolutionary disadvantages or selection pressure. Your original post suggested that all traits in the human body have a purpose, including traits which have no evolutionary advantage or disadvantage. If you want to talk about evolutionary (dis)advantages and selection pressure, that’s great, but now you’re moving the goal posts, and you’re not sticking to the generalization that struck me as incorrect. Fine. I hope I helped encourage you to move the goal posts. 🙂

        However, consider that all species, including humans, are works in progress. Even when there _is_ selection pressure for a species to get rid of a trait, that trait might still be present when you’re taking a look and puzzling over the trait’s “purpose” or “function”. And for this reason, labeling traits as vestigial doesn’t strike me as hubristic.

        1. Bob, that noise you hear across the country is the creaking of the ocular rotation in my eye sockets. I wrote what I wrote. It had absolutely nothing to do with teleology. If you really fantasized that it did, I can’t help you.

          1. You wrote that a purpose is ““evolved to make the organism more fit in its environment”, and you wrote of “the hubris of people who think that, just because they can’t figure it out, something evolved in humans has no purpose.”

            I don’t think it is a stretch to assume that you think that things which evolved in humans do have a purpose.

            Well…. ….male nipples evolved, they don’t make the organism more fit in its environment, and they serve no purpose as you define purpose. I think male nipples, like other vestigial traits, are a counter-example for you, which should cause you to reconsider your claim about hubris (and to reconsider the idea that traits which are present in the human body have a purpose.)

            I liked this topic because it is non-political. It seemed worthwhile to me to engage you in philosophy and science. Either show me why I’m wrong, or I’ll show you why you are wrong, and both of us will benefit. But if you’re not getting anything out of my comments, I’ll stop.

      2. In the ’60’s, the family car was this beige Chevrolet. There were three “trim levels”, the Biscayne, the Bel Air, and the Impala, and this baby was a Biscayne. Bel Air is a tony part of L.A., and an impala is a very fleet-of-foot antelope. What is a Biscayne, anyway, is it this swamp somewhere in South Florida?

        No A/C, no radio, heck, it didn’t even have a clock. It had a blank space on the dashboard, however, where the clock would go, that is, if the parents weren’t too cheap to purchase a car with a clock. Sitting in the back with the wind blasting in my face from the parents having rolled the windows down, the blank space in the dashboard was a constant reminder of what could-have-been.

        The human appendix and the male nipple is that sort of could-have-been — it is Nature’s marketing strategy to offer de-contented living things.

  6. Things that evolved in an organism generally did so for a reason, even if that reason no longer applies. Harmful traits tend to be weeded out of the gene pool in favor of beneficial ones. But often traits that seem to be harmful are being retained because they have a non-obvious benefit or a benefit that only becomes important under certain circumstances.

    A single copy of the cystic fibrosis gene protects against cholera, and the gene is most common in areas where cholera was prevalent. Sickle-cell protects against malaria. It seems the appendix protects against a host of bad things that can happen to our gut flora, and does the same in other mammals. In rabbits it probably formed the caecum (their small intestine makes a T intersection with the large intestine and caecum), which allows them to ferment grass for a second pass through the digestive system, which is why the world has so many freakin’ rabbits.

    1. But often traits that seem to be harmful are being retained because they have a non-obvious benefit or a benefit that only becomes important under certain circumstances.

      I have often daydreamed of humans having genes that only become beneficial in space. It turns out the some humans have genes that do help them deal with space related health problems but not as wacky as my daydreams.

      1. Humans have a huge number of traits that are beneficial in space. We are the only large animal on the planet that can survive there, which is odd if you think about it. Every other animal would be floating in poo and pee and flailing around with hooves or paws.

        Other advantages we have is the ability to store food, understand orbital mechanics, and the ability to push buttons. As far as this planet goes, we’re pretty much the only game in town.

      2. Return of the tail! That would be beneficial for zero-g.

        Of course, teleologically, that means God intended us to always live in trees.

      3. Speaking from a standpoint of spacesuit joint design, tales would be a disaster! They’d want to stick straight out and would always get hung in the airlock.

  7. “Teleological” isn’t an outdated idea, by the way. Every time you pick up a gizmo or other mechanism you’ve never seen before and ask “How does this work?” as you poke around at various buttons and other affordances, you’re doing teleology. And since living organisms are a type of mechanism, it isn’t inappropriate, and certainly not outdated, to study living creatures from a teleological point of view.

    The problem is that thinking teleologically can fall lead one to fall prey to the fallacy that a feature must have a function or purpose. Here’s a real life example: a limited run prototype of a plastic handle was created using injection molding. The handle had a mold line, which of course, was just a byproduct of the molding process. Later a colleague sent the prototype to a factory for mass production, and the people there decided to use rotational molding. They see the mold line, and they make a teleological fallacy – they assumed the mold line must be functional – (maybe it helps line up your grip?) and they replicated the mold line even though there was no need to do so.

  8. No, teleology is a specific word used in philosophy. It is not outdated at all, but it has a meaning that is not used in science. They are different paradigms.

    1. Jon, you are incorrect. The word is used quite often “in science”, although probably not in the fields with which you are familiar. It is used frequently in psychology andin artificial intelligence, to name two fields, although there are plenty more. Visit Google Scholar and search for the word to see what I’m talking about:

      https://scholar.google.com/scholar?q=teleological&hl=en&as_sdt=0%2C14&as_ylo=1990&as_yhi=2017

      One of my favorite machine vision papers uses the word in just the same way I’m using it here at Transterrestrial: ” Sensible Scenes: Visual Understanding of Complex Structures through Causal Analysis.” by M Brand, L Birnbaum, PR Cooper AAAI 1993.

      1. Rand was only using the word purpose to mean function and you throw your thousand dollar words around for no reason whatsoever. I looked at your list and nowhere do I see that these studies have used teleology as a substitute for “purpose”, which is all Rand was talking about. This is a silly conversation.

        1. I bet all of the studies listed in Google Scholar use the word “teleological” in the way I’m using it. If you would like to pursue this with a particular paper, provide an example. Hey, maybe I’m wrong. Additionally, I cited one specific paper – a theoretical machine vision paper – to demonstrate that it has a modern use in science.

          In any case, I used the word because I wanted to refer to a particular type of fallacy. As you probably already know, you can look up lists of different kinds of fallacies, some of which are labeled using words which I suppose might be called “thousand dollar” words or phrases such as “Post hoc ergo propter hoc” and “Tu quoque”. Here’s a list which includes the “teleological fallacy”: https://suchanek.name/texts/tor/fallacies.html

          My goal was to point out a fallacy in Rand’s thinking. Unfortunately, both you and Rand focused on the fallacy’s label – “teleology”- instead of thinking about the fallacy itself. If you don’t like the word, don’t use the word. And if you don’t like to be wrong, don’t commit the fallacy.

          2. “Whatever word you wish to use, I did not commit a fallacy.”

            Ha! That was a very convincing pronouncement!

            Rand, lets turn this around: under what circumstances would it *not* be hubristic to decide that a trait is vestigial?

            Here’s how I imagine this goes: Whenever a biologist has the opinion that a trait is vestigial, Rand Simberg can say “well, you can’t identify the trait’s current purpose, but it might have one.” And a good biologist would reply “Yes, it certainly might. I am betting on vestigial. Show me why I’m wrong.” Is the biologist being hubristic?

          3. Rand, lets turn this around: under what circumstances would it *not* be hubristic to decide that a trait is vestigial?

            I already answered that question. I’m sorry for you that your ego doesn’t allow you to let go of a failed argument.

            Here’s how I imagine this goes

            Your imagination is as flawed as your reading comprehension.

          4. Well Rand would crush that debate based on this new line of research.

            Your position is that the appendix does nothing. Medical researchers now note that it provides important protection by serving as a reservoir for gut microbes, allowing you to better survive things like diarrhea and helping to ward off other serious digestive problems.

            Seven percent of Americans develop appendicitis,and a whole lot of those cases might have been fatal in the pre-modern era. Additionally, most cases occur between age 10 and 30, not in the twilight of life Alzheimer’s, so they also carry a heavy reproductive penalty.

            The new paper Rand cited shows that mammals developed the equivalent of the appendix 30 separate times, indicating that the organ is so important that animals that don’t already have one go ahead and evolve one.

            So why would a smoothly functioning population of gut bugs be so important? Because survival on the savanna doesn’t allow sick days. Animals don’t get to take two weeks off to recover from a diarrhea. They have to stay with the herd.

            If the appendix didn’t itself cause so much trouble we might write it off as vestigial, but it does cause trouble. Our inability to produce our own vitamin C, for example, carried no penalty among fruit and fresh meat eaters, so the potential harmful trait didn’t carry a penalty until we undertook long (and wildly unnatural) sea voyages. But that’s not the case for the appendix.

          5. “Your position is that the appendix does nothing. ”

            That’s not my position. Above I said “The appendix might very well have the function of serving a reservoir for beneficial gut bacteria, but….”

            My position is that Rand, perhaps accidentally, made a general claim about traits in his original post. I didn’t take a position on the appendix’s function. Because I felt that Rand had over-generalized, I gave various examples above including heart disease, freckles,male nipples and even mold lines in manufactured objects. I also made a reference to Stephen J Gould’s paper on spandrels. I’m talking about the general case.

      2. So Bob-1 are you engaging in a teleological fallacy by assuming that the appendix and male nipples have no use?

  9. The appendix’s function would be more obvious if humans were still in the habit of eating grass, rather than the last ten thousand years of eating grass seeds (like corn, wheat, rice, and barley). It’s a rumen.

    I think rats are the only species as close to omnivorous as humans are, and we can digest things that even rats cannot, such as sawdust.

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