Irreducible Complexity

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Discussion by: Roedy

I spend a considerable proportion of my days debating creationists, debunking bogus irreducible complexity claims.  However, I came up with one on my own that stumps me. 

How did the dragonfly wing evolve?  It did not need a partial wing for warmth, or coddling eggs. Do we have any of the intermediate fossilised forms?  What did the partial wings do?  Would they have acted like grasshopper legs?

23 COMMENTS

  1. Yay, Roedy! Hope you are good.

    Good question. There are unlikely to be helpful fossil records, but one theory has it (I think) that because they always have a blood supply they may have been used for heat transfer. Perhaps catching the suns rays first thing to speed up up the capacity for early morning mobility. Growing bigger they may have progressed through to “falling with style” before real flight, maybe taking in noise generation, as you suggest, along the way to pump those muscles.

    It might be nice to use this thread to track down the best examples of “irreducible complexity” that any can come up with, so they can be dispatched?

    • In reply to #2 by phil rimmer:

      It might be nice to use this thread to track down the best examples of “irreducible complexity” that any can come up with, so they can be dispatched?

      That presumes (a) that we have enough knowledge to dispatch any claim of “irreducible complexity” and (b) that we actually need to dispatch any such claim. I honestly don’t know about (a), but I strongly disagree with (b). All too often we allow ourselves to fall into the trap where we are unable to explain something and a creationist takes that as proof that the thing being discussed must have been created by God. As soon as we start down that path, we will inevitably wind up a point where we can’t fully explain something, at which point the creationists will claim victory (ignoring, of course, all the pother things that we can explain).

      We have lots of evidence how complex structures evolve over time from simpler structures. We have zero evidence that anything was created by God. Any examples of apparent “irreducible complexity” are therefore just an indication that we haven’t yet figured out how it evolved and do not need to be “dispatched” to prevent creationists from claiming them as evidence for a creator.

      • In reply to #6 by godzillatemple:

        In reply to #2 by phil rimmer:

        It might be nice to use this thread to track down the best examples of “irreducible complexity” that any can come up with, so they can be dispatched?

        That presumes (a) that we have enough knowledge to dispatch any claim of “irreducible complexity” and (b) that we actually need to dispatch any such claim.

        Point well taken, BUT…

        I have often argued that irreducible complexity is not even a scientific theory (non refutable) so it is of no use. However, I have had much more traction with IDers when I suggest that any half credible set of possibilities of evolutionary stopping off points and differing applications for our given evolving feature in differing ecological environments, defeats the IDers belief that they have a proof positive. This actually works for them and its fun to dream up multiple routes to show up the willful poverty of their imaginations. They just love to think a brick wall is hit when its just the littlest of steps.

        One of the fun things about making up evolutionary paths is the predicting of possible fossil finds…

      • In reply to #6 by godzillatemple:

        In reply to #2 by phil rimmer:

        All too often we allow ourselves to fall into the trap where we are unable to explain something and a creationist takes that as proof that the thing being discussed must have been created by God.

        I couldn’t agree more. Irreducible Complexity seems to be a special case of the argument from personal incredulity(AFPI).

        AFPI goes something like this: I, Jane Doe/John Doe, personally cannot believe that X (for example, the wings of a dragonfly) could have occurred via the laws of physics and/or Evolutionary processes, therefore God must have done it.

        Like godzillatemple said, we really shouldn’t waste too much time dealing with such “arguments.”

        There is real debate out there, though, about why dragon flies have four rather than two wings – Some of this is explored in a study by Usherwood and Lehmann.

      • In reply to #6 by godzillatemple:

        In reply to #2 by phil rimmer:

        It might be nice to use this thread to track down the best examples of “irreducible complexity” that any can come up with, so they can be dispatched?

        That presumes (a) that we have enough knowledge to dispatch any claim of “irreducible complexity” and (b) that we act…

        In answer to creationists who think they win whenever we can’t come up with an immediate example of how something could have evolved, I always like to point out that, while science doesn’t yet have answers to every mystery, it doesn’t mean that it won’t discover them someday. All of the natural phenomena we understand today, we understand thanks to science. In the last 200 years, science has given us all the amazing things we know about life, our planet, and the cosmos. The number of real questions answered and mysteries solved by religion over the thousands of years it has been around? Exactly zero.

        • When confronted with such challenges about irreducible complexity, I like to be cool, show an attitude of humility and willingness to learn, and ask them: “What is your theory?” They usually do not have a valid hypothesis to offer. If they say “God did it” you can go on asking how did he make it, in which order did he assembled the pieces, how long did it take for it to be made, and so on. They are on dead end since the beginning of the conversation by saying that God did it, they just don’t realize it. If we keep the humility attitude they will see that science is looking for answers, explanations, while religion is looking for knowledge stopping.

  2. You could extend the question to every insect wing (as bird and bat wing evolution is a bit easier to understand). The question for dragonflies specifically is why are their wings different to other insects; dragonfly wings are independent, whereas most 4-winged insects lock the front and back wings together to work as one. Dragonflies are a very old species, which is probably why they are the most highly developed – they can out-fly pretty much all other insects, have excellent vision, and hunt “on the wing”.

    As to your question, there are a few schools of thought. Extended body scales? Deformed gill plates? Google is your friend!

  3. I don’t even know where to find a Creationist to debate, how do you get all the fun? So when you find out about the wings will someone then bring up fly legs, or maybe beetle eyes? You know there’s no end to this thing. One interesting idea that is emerging is that natural selection might not be the only force driving evolution. There could be an underlying reason for biological structures. Here is a link that better explains it.
    Statistical physics of self-replication

    • In reply to #8 by A3Kr0n:

      There could be an underlying reason for biological structures. Here is a link that better explains it. Statistical physics of self-replication

      Great paper. The underlying principle ha been argued for for quite a while (Complexity speeds the Universe to its heat death and equilibrium.). This is looking provable though now the maths is good.

      Might we find more complex life in higher energy flux environments? Should SETI target hotter bigger sols?

  4. Hi Roedy,

    Good on you for fighting the good fight. You don’t need to answer every question they come up with though, you only need to demonstrate the principal and show examples of highly complex things evolving to show that the system works.

    However, I can think of a couple of things off the top of my head that may give an explanation. There are spiders that use their abdomen to signal to mates insect wings may have started as a visual display and latter as they became bigger evolved into useful wings. Insects being small have a high surface area to mass ratio, this allows insects to fall at slower speeds than say us. So even a small protrusion would have an impact on how far it could get blown in the wind or how far it might be able to glide. A jumping insect might be able to extend the distance it lands from a predator in this manner, jump high and float a few feet away- particularly on a windy day, once a rudimentary flight surface evolved it would be easy for natural selection to select for retracting then flapping wings. Again no idea if this is true or likely but you don’t have to know, only be able to propose a possible solution and look for fossils.

  5. We’re all aware of the burden of proof. Why don’t the creationists proof that something is irreducible complex?

    There is a significant flaw in their argument. Creationists don’t just state that dragonfly wings did not evolve, they are stating that dragonfly wings could not evolve.

    How on earth are they going to prove such an statement? I don’t even think that’s possible.

    So far, every example of irreducible complexity they’ve come up with, has been refuted.

    • In reply to #13 by Thomas Hobbes:

      P.S. You don’t have to show how dragonfly wings actually have evolved, only how they may have evolved. That’s enough to refute irreducible complexity.

      This is exactly the point. IDers don’t understand about ill-formed hypotheses or that Popper took proofs positive out of every scientist’s vocabulary leaving it only for the mathematicians. One good account of a possible evolutionary path is something they can grasp.

  6. I don’t see the point of arguing every case. Let’s put it this way. Evolution is the only reasonable and objective scientific mechanism for producing change in reproducing animal and plant life (that we know of). No other concept is even close. The dragonfly has wings. They must have evolved from simpler forms, even if we don’t know precisely how.

  7. Just wondering what you do about the irreducible complexity claims that aren’t bogus?

    Here’s my amazing theory on dragon fly wings:

    Insects evolved the ability to morph. An extremely flexible approach to enable adaptation across multiple environments. Which means the same organism can be optimised for very different environments and food sources in different phases of their lives. But significant metabolic and structural changes are involved. Which requires the organism to withdraw from active living and to exist for a while undergoing metamorphosis.

    Human males undergo a similar metamorphic transition between juvenile and mature phases. Following a prolonged period of post-juvenile hard work and focusing mostly on reproduction the fully mature specimens then suddenly and dramatically change their body shape to accumulate a camel like hump of special tissue normally at the front of the abdomen. They also tend to change primary food sources from drinking things like milk as a juvenile to preferring beer and whisky once fully matured. (Typically several years in barrels.) Possibly an adaptation to impede sex and therefore deter future reproduction after the organism has effectively passed its use-by date.

    In the case of the ancestor of the dragon fly it might be possible that fragments of similar structures that comprise a chrysalis used by modern day moths and butterflies might remain attached to act as a large surface area to enable wind-borne distribution, similar to how some spiders can employ web stands to be borne aloft and distributed by air currents. Panels of some kinds of chrysalis already have the relevant shape and size to become adopted as wings. Possibly the origin of insect wings may be linked to the way chrysalis structures are secreted prior to metaphorphisis, as in insects like butterflies.

    This isn’t supported by any evidence. But might be an example of how a ready-made, no batteries or assembly instructions required, elaborate proto-wing structure might suddenly appear out of nowhere in the evolutionary process. Mutations that produce this kind of wing-like structure being essentially a dysfunctional failure of chrysalis secretion and formation. Possibly happening too early in the process, or possibly with neotonous features failing to be turned off and so being retained after the metamorphosis is complete. This kind of gene disruption avoids the need to evolve a complete operational wing as a single mutation. i.e. the original wing was a deformity rather than normality. But which proliferated with innumerable variations because it would have been subject to aggressive selection pressure because the afflicted organisms became increasingly more dispersed at a time in the world’s history when getting blown the furthest by the wind to more or less anywhere else further away would have been a good thing, most ecological niches as we know them today being effectively unfilled.

  8. How did the dragonfly wing evolve? It did not need a partial wing for warmth, or coddling eggs. Do we have any of the intermediate fossilised forms? What did the partial wings do? Would they have acted like grasshopper legs?

    Joel Kingsolver and Mimi Koehl propose that insect wings were originally solar panels to help regulate body temperature, and later were co-opted as flying instruments, perhaps with an intermediate “bi-functional” stage as both panel and glider, once the panels increased in size enough to become aerodynamically suitable. Their paper can be found here.

    It’s also interesting to note that dragonfly larvae have a small case on their backs from which the wings emerge when they moult into their adult forms. While I’m not sure what function it serves, it could represent what a precursor species would have looked like, and seems to be a neutral, perhaps vestigial, feature.

  9. @OP – How did the dragonfly wing evolve? It did not need a partial wing for warmth, or coddling eggs. Do we have any of the intermediate fossilised forms? What did the partial wings do? Would they have acted like grasshopper legs?

    Dragonflies are insects, and insects are arthropods descended from marine arthropods such as shrimps.

    Insect bodies are replicated segments and antennae, etc. are mutated from legs, as work on fruit-flies shows.

    There are two likely sources of insects developing flight. First their ancestors already had legs for swimming, and redundant gills which could be modified. Second:- very small creatures such as baby spiders, can fly in the wind without wings anyway.

    The have been experiments with primitive bristletails which show they can glide from tree to tree.

    http://blogs.sciencemag.org/origins/2009/03/how-did-insects-get-their-wing.html

    Exactly how insects evolved flight is a heated issue, in part because the fossil evidence for winged insects remains full of gaps. But living insects that are similar to ancestral species could also shed light on the origins of insect flight. In a study reported online this week in Biology Letters, researchers report that bristletails, primitive, wingless insects that live in the tropical forests of Peru, can use long antennae-like filaments extending from their rear ends to help them glide to tree trunks as they jump or fall from forest canopies. These observations suggest that winged insects evolved on land, rather than from aquatic habitats, the authors conclude.

    According to the fossil record, before about 390 million years ago, the planet was populated by six-legged wingless creatures resembling bristletails and similar living insects called silverfish—those early creatures are considered to be the ancestors to all current-day insects. There’s then about a 65-million-year gap in the insect fossil record. The next known fossils date to about 325 million years ago, and they include insects with and without wings. Given the lack of a fossil showing an intermediate stage of an insect wing, scientists have been left debating two primary theories: that wings developed either from the gills of insects living in water or from extensions on the sides of a terrestrial insect.

    To address this debate, tropical insect ecologist Stephen Yanoviak and his team turned to a species of wingless bristletails called Archaeognatha Meinertellidae. Genetic phylogenies suggest they are closely related to the species at the root of the evolutionary tree of insects, and they also lack any aquatic form to help rule out wing development in water. The researchers were interested in whether these bristletails could use their filaments or antennae to help maneuver, or glide, during a fall. Yanoviak says that this ability would have been useful about 400 million years ago when the first trees appeared and wingless insects began to feed on lichens and debris in tree bark. If those insects encountered a spider or other predator while up in a tree, they would need a good escape route. But they couldn’t just jump off the tree if they couldn’t guide their fall away from nearby quagmires and to a safe landing point instead.

    To explore what aerial control these insects have, Yanoviak and his colleagues collected nearly 200 Peruvian arboreal bristletails and separated them into six different groups. One was left untouched for a comparison, and for each of the other five groups, researchers removed the lateral filament, the medial filament, the medial and one of the lateral filaments, half of all the rear filaments, or the insects’ antennae. When Yanoviak dropped the insects from the top of a forest canopy, he found that 90% of the untouched bristletails successfully glided to a nearby tree before reaching the ground. The insects with either their antennae or their rear lateral filaments removed had about the same overall success rate, but it took them longer to get to their target tree. And those lacking their middle bristle, a filament extending from the insect thoracic segment, often lost the ability to glide under control and wound up on the forest floor. (Here’s a video from Yanoviak showing normal bristletails gliding from a tree.)

    There is some scientific debate, because there is a gap in the fossil record, which translated into IDiot, says, “science does not have solid evidence or a consensus, THEREFORE – god-did-it-by-irreducible-complexity”!

    Insect wings are an evolutionarily significant novelty whose origin is not recorded in the fossil record. Insects with fully developed wings capable of flight appear in the fossil record in the upper Carboniferous (ca. 320 million years ago), by which time they had already diversified into more than 10 orders, at least 3 of which are still extant. Wingless insects are observed in the fossil record as early as the Silurian (ca. 400 million years ago) (Engel and Grimaldi 2004). The intervening fossil record is poor and no fossils showing intermediate stages in the evolution of wings have been identified (Kukalová-Peck 1991). Unresolved questions about wing evolution include from what ancestral structure wings evolve, what the ancestral function of wings was, and whether wings evolved in an aquatic or terrestrial lineage. Biologists have looked to additional data sources, such as development. http://jhered.oxfordjournals.org/content/95/5/382.full

    There is considerable debate and various hypotheses, on this last link.

  10. Hi Roedy,

    I personally have no time for people who push ‘Irreducible Complexity’ as a rational answer for anything in this universe. Even its very name is pure rhetoric and does not invite discussion! Any concept that is making a claim, yet does not offer itself to independent peer review, is in my view itself flawed. As has already been stated – science does not have all answers, but what answers we do have have come from science…

    Probably the most well known and persistent IC claims, just like the Dragon fly wings, is that the eye is ‘irreducibly complex’. What we have with this IC claim – as is with all IC claims – is an excersise in pure semantics. Let’s think about it for moment. How many forms of eyes are there in the world? Many thousands. What have they all in common? They are all light receptors, it does not matter how advanced a species has evolved its eye, to the most simple eye which can only perceive shadows – they are all light receptors. If we remove a major component of the Human eye, the lens for example, it will become a more simple eye. It will still perceive shadows, just like the eyes of simpler species – yet still remain an eye! Remember also that you can reduce the eye down to simple proteins. Everything in our bodies is made from proteins. The components were there and millions of years of trial and error put them together.

    So we can clearly see, even when looking at the macro, that an eye is an eye as long as it still has the function to perceive light. Add a lens and it becomes a light receptor that can focus an image. Develope two eyes in binocular fromation and you have the ability to judge distance – this is why many predators use this arrangement. The point I’m making is that it’s all progressive development over a vast amount of time. Reduce the complexity of the eye and you just make it a simpler eye. And remember, IC also claims that if any parts were missing from the eye those parts will become redundant. Does this mean that a proteins are redundant if not contained within the eye? Of course not. Everything in our body is made from proteins…

    The Human eye is justifiably complex, but it also flawed. We already know as ‘simple’ humans how we could make it better, how much more so would an all knowing vastly superior being improve on the design? Why did he not do so to begin with?

    For your Dragon fly question I would suggest that you contact a local university or society, like the Royal Societies we have in the UK. I’m sure they could point you in right direction for an answer. For what it’s worth, I know that the wing structure avails the Dragon fly with superior offensive and defensive manoeuvrability – an important evolutionary advantage to support the longevity of most flying species. Paste this link in your bowser, it may also give you the answerers you require:

    http://pandasthumb.org/archives/2009/12/no-longer-sleeping-in-seattle.html

    Remember you’ll always be fighting against the notion of ‘if we can’t explain it, it must therefore be made by God’. Even if a thing can’t be explained, it still does not offer any supportive evidence whatsoever for a God. It simply shows, that in our present state of ignorance, we are unable to explain it. As stated before, science doesn’t stand still, it will find an answer – just like it always has…

  11. While creationists are are demonstrating their ignorant incredulity, scientists are getting on with studies as usual!

    3D insect flight: footage captured from inside a fly – http://www.bbc.co.uk/news/science-environment-26741402

    A team of scientists from Oxford University, Imperial College, and the Paul Scherrer Institute in Switzerland have used very intense X-rays to film inside an insect as it flies.

    The footage is a 3D reconstruction, made up of several X-ray images, and shows a blowfly’s flight motor – the anatomy that powers its flight.

    The researchers say the videos offer a glimpse into the inner workings of one of nature’s most complex mechanisms.

    The results are published in the journal Plos Biology.

    • In reply to #21 by Alan4discussion:

      While creationists are are demonstrating their ignorant incredulity, scientists are getting on with studies as usual!

      3D insect flight: footage captured from inside a fly – http://www.bbc.co.uk/news/science-environment-26741402

      A team of scientists from Oxford University, Imperial College, and the…

      ‘…scientists are getting on with studies as usual!’ – Great example of this Alan4discussion, excellent video. As per usual, our advancement in knowledge stems from real credible science – and not a creationist in sight…

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