Today’s video, part of the PBS/It’s Okay to Be Smart collaboration, highlights the “dumbness” of evolution: the fact that it has no foresight, and therefore devises solutions—I’m speaking metaphorically here—that are less perfect than an engineer could come up with de novo. One of the most famous jerry-rigged and imperfect “adaptations” is the mammalian recurrent laryngeal nerve (RLN), which is described well in the video, along with an animation that should be useful for teaching (I discuss this as evidence for evolution in WEIT, but there’s no substitute for a good animation).
Creationists have denigrated this evidence for evolution, suggesting that the recurrent laryngeal nerve has other functions that are essential (it apparently branches off some smaller nerves that go to other places), but even that’s not convincing since bad design, like vestigial traits (e.g., the penguin’s “wing”) can be coopted later by selection to serve new functions. Only evolution can explain this circuitous route. After all, it’s only the left laryngeal nerve that makes this detour down to the aorta and back. If you’re a creationist, you have to then explain why God designed the system so that only that left nerve needed to have those functions. But that’s ad-hoc-ery, for evolution explains why only the left nerve bends this way—based on the asymmetric evolutionary displacement of the artery that the nerve is constrained to loop around. Here’s the video:
One beef: this series continues to describe natural selection as involving differential survival of individuals, although here they do correct “survival of the fittest” to “survival of the good enough.” I wish that they’d note that natural selection is actually differential reproduction of genes, and survival needn’t be involved. Now it may be too arcane to distinguish between differential reproduction of genes and differential reproduction of individuals (the genes’ vehicles), but I wish they’d take one video to make this clear. Since I haven’t yet seen the final six parts, perhaps they will.
If you haven’t seen the video below from Britain’s Channel Four show “Inside Nature’s Giants,” watch it, for Richard Dawkins actually narrates the dissection of the RLN from a giraffe during an autopsy. This is the first dissection of a giraffe’s RLN since 1838—21 years before Darwin provided the explanatory framework:
The RLN is one of my favorite examples of jury-rigged design. It is interesting to contemplate the probable situation with this nerve in the long-necked sauropods.
I read somewhere the hypothesis that, since dinosaurs were growing fast and tending towards homeothermic regulation, that they solved their metabolic problem by stuffing their stomachs and doing the food processing from there on. If I remember correctly the models implied that way an average sauropod could harvest vegetation twice as fast as the average mammal.
Maybe that unburdening of the skull/neck functionality solved any RLN timing problems as well?
Oops, too many “that”s in there.
Are you trying to subtly correct our host by writing “jury-rigged” in your comment?
It seems that “jerry-rigged” evolved from “jury-rigged” via horizontal word transfer from “jerry-built.”
Pinker? You’re being paged.
🙂 I had to read your comment a few times to finally understand my mistake. But if my comment gets re-posted a few more times then maybe it will catch on and our language will evolve in a new direction.
You didn’t make a mistake. “Jury-rigged” is correct. “Jerry-rigged” is commonly accepted as an alternate spelling, and it is probably used because people confuse “jury-rig” with “jerry-built.” A pedant would say “Jerry-rig” is wrong. Anyone interested in more detail can google it.
Also, Hat-tip to Matthew Cobb, I recently read the novel In Hazard based on his recommendation. It contained a line that went something like, “In a sailing ship we could have rigged the jury-sails, but in a steamer without steam there was nothing to do.”
I guess “Jury-rig” is a nautical term, to do with rigging jury sails when the main sails are blown or blasted away.
You don’t have to be a pedant to note that ‘jerry-rigged’ is as wrong as ‘might of been’.
In the UK we use the term “Jerry Built” to describe faulty design and or building work.
But skeptics will wonder why there are so few cases as the one at hand. Yes, I heard the notion expressed that there are many such cases of “poor design.” But we are, without pause, singing the praises of the perfection of nature. Those perfections seem to be endless. So although it may suffice to have a single instance of “flawed” design such as the RLN to undo ID, it must give one pause, the practically infinitude of perfections of nature.
The Burgess shale specimens! The Ediacaria fauna! All perfect, at least on the outside. The most egregious thing about nature–its perfection. If nature is tweaking away in effecting evolution, why not an infinitude of imperfections? And finally in this regard, the mechanism of evolution, natural selection, is by definition opportunistic. One must wonder how an opportunistic modus operandi can have produced thaenature we know,
“But we are, without pause, singing the praises of the perfection of nature.”
Seriously, the perfection of nature? I have yet to see an example from nature that a clever engineer couldn’t improve upon. Starting with my prostate.
On the other hand, when evolutionary techniques have been applied to the design of “engineering” components, e.g. electronic circuits implemented by programmable arrays of logic gates called Field Programmable Gate Arrays (FPGAs), then while the system does produce effective solutions, the working of the circuits can’t be explained by conventional engineering. One working tone discriminator, for example, used 40 gates, but no clock circuit (which rather begs the question of how the tones are discriminated) ; another version had one block of the gates disconnected from the rest.
Which is very peculiar. But it takes place entirely within the tightly constrained properties of a microprocessor chip, completely designed by humans. But people can’t explain how they work (or indeed, why they stop working – temperature restrictions were far tighter than the design criteria of the chips themselves).
More recently NASA have continued to use similar techniques for antenna design.
Just because it’s engineering doesn’t mean to say that it’s designers understand how it works.
Several problems
1. “Halting problem” in computers cannot be explained by computer engineers
2. The right RLN nerve course is different to left?
3. Physics/engineering is COMPLETE?
No, to all of the above.
Not one argument of which makes evolution less true by one iota.
I think you are conflating the issues:
1. Is entirely in agreement with the point you are making. I have exampled “halting problem” and you have “FPGA” to illustrate the same point. “NO” is not an effective answer here.
2. The right RLN nerve course is different to the left. This is a fact. By you saying “NO” does not make it false.
3. You may not be aware of Pierre-Simon Laplace’s (1749–1827) confident statement, “Physics is complete”. This of course was proved untrue by the advent of Einsteinian physics. Similarly even today, physics may not be complete. And therefore today we may not be able to explain all the facts. Again “NO” is not an effective answer here.
AIUI, the “halting problem” is fundamental to information theory, and therefore maths and computing.
I read “right” as meaning “correct”. Left-Right asymmetry is something to talk to echinoids about.
No-one who follows modern physics thinks that it is complete. Everyone KNOWS there is a gaping hole between General Relativity and Quantum Theory. The difference is below (at last count) the 12th significant digit.
Theology still hasn’t got the question of “zero, one or many” for the count of “gods” settled. that’s the first significant digit.
Please call me when the difference in significant digits drops below 10 – that would mean that theology has produced some testable result.
Since nature considered 99.9 % of species too imperfect and caused them to go extinct, isn’t it application of a wee bit of special pleading/selection bias to claim perfection?
The analogy of ‘design’ is flawed anyway, the process tries to hill climb a recipe of what worked the last generation. If evolution could place the parts ‘just so’ it may have helped, now it is more like The Swedish Chef crying “Børk! Børk! Børk!” and fighting the Lobster Banditos for any improvement.
No, they’re not “perfect”, they’re just pretty good.
For one thing, a “perfect” animal would never get eaten by a predator. A perfect animal would never die before leaving descendants. A perfect animal would never die of illness or starvation. Therefore nearly all animals fall short of perfection on those counts alone.
Suffer through a bad anal fissure and you won’t be so keen on nature.
Or for that matter, just have a baby.
There are many obvious mistakes, but as long as we are complaining about multiple use orifices and their haphazard placement we should mention having the birth canal pointing down in humans instead of being rerouted to the front. [Now I hear evolution protest: “Butt, I did my best!”]
That sharkasaurus isn’t very well designed. There’s no laser on it’s head for starters. And it’s certainly possible to mount one there (see this shark model), as well as jaw-mounted chain-saws (put your coffee down AWAY from the keyboard before clicking on the image for a better view. Srsly.).
The bit that implies we evolved the ‘recurrent’ part of the RLN with lungs is likely wrong. Fish had lungs already. Not just the ones that eventually gave rise to the tetrapods. Lungs were pretty widespread among the fishies.
I think what went awry with the RLN is that the tetrapod line evolved necks, which forced detachment of the pectoral girdle bearing the front limbs from the skull. You can see early experiments in this scenario with the various fossils of transitional forms between lobe finned fishes and tetrapods. Some of these ‘fishes with legs’ had a skull detached from the pectoral girdle.
“Survival of the good enough” is still not good enough. Suppose that we have a “good enough” genotype, and another comes along which is 1% better. In spite of the previous genotype being good enough, it will tend to lose out.
As long as one has produced viable progeny, Nature doesn’t “give a damn” about imperfections.
“And what comedian configured the region between our legs—an entertainment complex built around a sewage system?” — Neil deGrasse Tyson