A rumination on gears

As promised we now return to the topic of animal gears. I begin by admitting that my memory fails me for although I can tell you that the research which first announced this discovery appeared in September, I cannot recall where I learned of it. My best guess is that I came across some micrographs while searching for images to illustrate a recent, and not unrelated, post which concerned the leaping ability of the flea. The internet being what it is I now know that this story has achieved nearly viral status; it was the subject of a report on NPR, and was even the topic of a post at another WordPress blog. The story is a one which involves the nymphs of a little Planthopper by the name of Issus. In much the same way as the flea, Issus leaps great distances as it moves from place-to-place. To jump in as straight a path as possible it is important that Issus’ rear legs be in perfect synchrony. You can imagine how asymmetries in jump trajectory could be generated if one leg or the other lead, lagged, or otherwise jumped-the-gun during launch. As a mechanism to ensure that the legs act together, a tiny set of gears may be found along the trochanter which is, in human terms, much like a knee joint between the coxa and femur of the leg. The action of the gearing is to synchronize the legs by providing a mechanism which links their movements.



Interesting, to be sure, but what strikes me most about reports of this discovery is the tone of surprise adopted by nearly all who describe it. Is it because people believe so strongly that only humans are capable of feats of engineering and good design? Do we not understand that a great number of human architectural constructions are simply mimics of nature’s own? A long-ago post about mimetics which appeared here focused on the many parallels between natural and artificial forms, and recognized that these parallels fostered the development of the field of Biomimicry which looks to nature for answers to solutions to human problems. So, given that solutions to many of our engineering challenges had already been solved, perhaps millions of years ago, why are we surprised when we discover something like Issus’ geared legs? Perhaps because the first principles of good gearing were developed and practiced by humans, including Leonhard Eular, back in the eighteenth century such that people think that we got it first? Guess what? We didn’t.


The leap of Issus at 5000 frames per second.
[Images were sourced from Daily Mail, Why Evolution is True, and bookofjoe.]

8 thoughts on “A rumination on gears

  1. What you say is so true, and in fact engineers and architects have often looked to nature for design ideas, because she’s so good at problem solving and creating 🙂 The images are interesting if a little creepy … like 3-D X-Rays!

    • We’re certainly in agreement there Seonaid … there’s no bettering nature’s designs. And, on the matter of scanning electron micrographs … I too have always liked their look; very cool indeed.Thanks for stopping in this evening. D

  2. I think there are limited options of how to move things in our three-dimensional space and how to optimize the consumption of energy or achieve a certain goal with minimum force – you have to obey the principles of mechanics. Thus if evolution had millions of year to tinker with it – it would be a surprise if she hadn’t “figured out” most of these options already.

    • I very much appreciate your last sentence. ” … if evolution had millions of years to tinker with it – it would be a surprise if she hadn’t ‘figured out’ most of these options already.” True, true. Dawkins once wrote that the improbable becomes possible … given enough time. D

  3. Indeed where does it start? Once again I am reminded of the awesome power of happy coincidences. Small wonder that so many are apt to mistake this for the deliberate, studied acts of a master engineer. But then again there’s always the argument which insists that the real design was in the creation of so intricate a machine that it would inevitably lead to such perfection. As for me I have learned to accept the happy conundrum of “relative perfection.” The current status is the best of the lot that survived. As such it does the job extremely well, but there will always be opportunities for even better “solutions” and, even more interestingly, opportunities for change agents that throw the whole thing sideways …
    and, thusly invite nature’s random engineers to offer improved “designs briefs” for the harshest of all judges: survival.

    Been working on a (1) an eLearning proposal for a software security firm and (2) a talk for next week. Enjoyed the break. 🙂

    • Your response reveals a deep understanding of the issue of design in nature. You hit the proverbial nail on the head and managed to do it with words and phrases which flowed poetically. Many folks have a very difficult time with the philosophical position of the happy coincidence. I was going to say, ‘I wonder why;’ but, alas, I know exactly why (and so do you). I will also point out that when you describe the process of evolutionary change as moving ‘sideways’ I was astounded (I don’t know why … I have come to expect no less from you) … even among professionals the issue of progress in nature can be a sticking point. But you and I, and many others, are in agreement. Issus is no better in any cosmic sense, than any of its close or more distant relatives. It simply happens to be in possession of an interesting adaptation which fits its particular circumstance. It is no better and no worse … simply different. If and when evolutionary change occurs it moves populations exactly sideways. Perhaps evolutionary theory is your true field? D

  4. I love these SEM images! One of the highlights of my undergraduate career was getting to use the scanning electron microscope for a project on the development of trichomes on that fuzzy purple houseplant, Gynura. I’m enjoying your scientific digressions these days, keep at it!

    • Hearing (reading) you say so makes it worth the time it took to put it together. Really. Things have been just so busy that I haven’t had even a few hours to be out and about with the camera. Truly frustrating. But, I have enjoyed just writing about things I find interesting. It’s so very nice to know that you do enjoy them. It’ll be nice to see and talk to you soon! D

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