Sunday, May 9, 2021

Why the appendix is NOT evidence for evolution

Ordinarily, I would never consider a sit com to be representative of any group but I'm going to use a scene from The Big Bang Theory as the backdrop for a discussion about the appendix. I'm doing this for a couple of reasons. First, I don't think anyone would argue that a vast majority of evolutionists consider the appendix to be vestigial so it's not like the show misrepresents this attitude. Second, it's just a funny scene and I'm going to exploit it for the sake of making my blog more interesting.

Enjoy!


Isn't that hilarious? Anyway, back to business. As I've already said, the appendix has been touted by evolutionists as the champion of vestigial organs. The theory of evolution virtually demands that there be vestigial organs and so, when the label of “vestigial” can be attach to some structure, they are quick to trumpet it as evidence for their theory. I cannot recall ever having a discussion of vestigial organs without the appendix being used by evolutionists as an example.

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By way of definition, a structure is considered vestigial if it has lost all or most of its original function. Even if the structure has function, it can still be considered vestigial if it doesn't perform its original function. That definition is somewhat circular because it assumes the organ once had another function. The wings of flightless birds, for example, have been called vestigial only because they are believed to be descended from flying birds. If the wings were never used for flying, then they can't be vestiges of flying wings, can they? I believe penguins' wings have always been used for swimming. Do evolutionists believe penguins once flew? I guess they do but it's only because they believe penguin ancestors could fly that makes penguin wings vestigial. Thus I say their evidence is circular. //sigh//

Every definition I've heard of vestigial suffers from a range of weaknesses but I'm not going to quibble over the definition of vestigial now. Instead, I'm going to question the idea that the appendix is evidence for evolution at all.

According to evolution, the appendix evolved in some ancestor of humans and once served an important function (or at least it evolved to serve some function). Since we are descended from this supposed ancestor, we have inherited that structure but, over the many generations of mutation and selection leading from the non-human ancestor to us, the appendix has lost its original function. For this reason, it's sometimes called an “evolutionary leftover.”

Humans are not the only creatures with an appendix. Dozens of mammals have appendixes – but not every mammal. Here's where the theory starts to get thorny. According to the theory of common descent, we should be able to trace the appendix along the so called “nested-hierarchy” where all the animals which have an appendix also share a common ancestor. The problem is, there is no predictable pattern among the mammals with appendixes. The appendix appears in some species of primates, rodents, and even marsupials but is absent from the intermediate groups linking these species. It's not at all what we would expect if evolution were true.

Failed predictions are usually considered evidence against a scientific theory. However, the fact that the presence of the appendix follows no predictable pattern hardly raises an eyebrow among evolutionists. As is often the case, they invent ad hoc theories to explain the failed prediction. Here is a quote from Sciencemag.org:

In a new study, published online... in Comptes Rendus Palevol, the researchers compiled information on the diets of 361 living mammals, including 50 species now considered to have an appendix, and plotted the data on a mammalian evolutionary tree. They found that the 50 species are scattered so widely across the tree that the structure must have evolved independently at least 32 times, and perhaps as many as 38 times. [Bold added]

Give me a break. The structure “must have” evolved 30+ times? There's another possibility, you know. Namely that the seeming random appearance of an appendix is evidence that the creatures on the “tree of life” are not related in an evolutionary sense. I wonder if the scientists even considered that possibility.

When creatures that aren't closely related share similar features, it's attributed to convergent evolution. According to this idea, there is sometimes a “best” solution to make a creature better adapted to its environment and “nature” will happen on that same solution time and time again. In the case of mammal digestion, the appendix must have fit some important need so well that “nature” created one on at least 30 occasions! But that “just so” story, that the appendix evolved so often because it was the “best solution,” stretches credulity when many evolutionists claim the appendix is vestigial in most of the creatures that have one!

So let's wrap this up: The appendix appears in no discernible pattern on the so called, “tree of life” which calls into question the entire concept of common descent. We have to believe the appendix is so important that it evolved independently 30+ times but it's also so unimportant that most creatures that have one don't need it.

Hmmm. Please explain to me again: how is the appendix evidence for evolution?

2 comments:

  1. Darwin referred to vestigial structures as "rudimentary." "Vestigial," as you note, implies an evolutionary explanation: that these structures in an ancestor had additional functions, which were lost in the course of evolution. However, one can recognize these structures without reference to evolution. Penguins have wings. The function of wings in birds, normally, is to fly, yet there are entirely flightless birds. These wings lack the most conspicuous function of their homologous structures in other species.

    Minor side note: penguins are descended from a flying ancestor. That ancestor might not have had enough of the distinctive features of penguins to qualify as a penguin itself.

    Note that "homology," likewise, can be defined without reference to evolution; Sir Richard Owen did so: "the same organ in different animals under every variation of form and function." Or, to rephrase, detailed similarity in structure beyond that required by similarity in function. Evolution -- common descent with modification -- is adduced as an explanation for the homology between, to pick classic examples, a bat's wing, a whale's flipper, and a human arm and hand, but the homology can be recognized without invoking evolution.

    So can the vestigial nature of the plantaris tendon that most people have in their lower legs: it is obviously homologous to the tendon that, in nonhuman apes, lets them clench their feet into fists, but it doesn't serve that function (or any discernible function, really) in humans, and is extremely variable in size, shape, and attachment points in humans.

    The basic mammalian gut gets modified a lot: mammals differ in the number of stomachs (specialized expansions of the gut) and other features. It's not that shocking, really, that an extra digestive chamber should evolve near the junction of the small and large intestines, or that, given that some animals get along without such a chamber, that it should become vestigial or rudimentary in multiple lineages independently. An enlarged cecal pouch seems to be connected to a diet heavy in leaves; diet is one thing that can change over time as a population evolves.

    I note that one definitely evolutionary argument for regarding the appendix (at least in humans) as vestigial is that it is extremely variable in size, shape, and orientation with respect to the rest of the gut. Organs under strong selection are expected, generally, to be very similar; extreme variation implies that none of the variants have much effect on fitness and that the variable features are not functional.

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    Replies
    1. Steven J,

      It's great to hear from you! I mean that sincerely. I knew my time away from blogging would mean that I would likely lose many of my regular visitors but it's nice to know that perhaps my most regular visitor has found my new blog. For all I know, God has impressed on me the urgency to blog for the sole purpose of reaching you! I know we've butted heads a few times but, at the end of the day, I'm interested in winning you to the Lord! If you haven't figured that out yet, then I've done a very poor job. I apologize.

      One glaring problem with the evolutionary theory, one that I didn't discuss above, is the contradictory idea that, while the appendix is considered vestigial (a useless leftover) in humans, it's still such an important organ that it evolved independently at least 32 times among mammals! It doesn't make any sense. It makes even less sense when we see that the appearance of the appendix follows no discernible pattern along the imagined family tree of mammals. Why?

      Steven J, you're clinging to a theory propped up by ad hoc explanations. Why not just let it go and accept the far more reasonable explanation – namely, that there is no evolutionary tree of life and the appendix is a useful structure placed purposefully by the will of the Creator? I'm praying that you'll see that.

      Thank you for your comments. I intend to get to all of them even if it takes a couple of days.

      God bless!!

      RKBentley

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