You will have noticed, if you have been paying any attention at all throughout this blog's existence, that I do not have a particularly high regard for Homo Sapiens Sapiens when it comes to planet management. Well, all that could change over the coming years.
You see I came across a small but active field of scientific endeavour the other day, biomimetics, that I thought it might be good to share with you in the absence of anything else to do with my time now that the 'book' is finished. Biomimetics, or biomimicry, is the study of how examining Mother Nature and her solutions to design problems, honed over three billion years, might help humans to overcome design issues with their current problems and concerns.
Have you ever wanted to be Spiderman? Not so much the web-weaving and flying through the air on extruded silk but the ability to climb walls, even glass ones. It has always been a problem for firefighters; their ladders have never been long enough for the kinds of buildings you build nowadays. What if you could climb up the sheer, vertical surface of the building and rescue the damsel in distress; how cool would that be? Well, maybe by studying nature, you might gain the ability.
You see, Mother Nature has already solved the problem! The gecko, a small lizard, is able to run up vertical walls, even glass ones, very fast and can even hang upside on ceilings providing a bit of the gecko is on the wall. MG says that you see them all over Greece doing just that. So, do they have sticky feet? Yes, but not in the way you might think.
The big problem with 'glue' is that it has to be strong enough to hold your weight but weak enough that you do not get permanently stuck to the surface. This is enormously tricky to manufacture since it is all dependent on the size of the gecko; you would need varying strengths of glue dependent on the weight of the individual gecko. This would be difficult for you and just as hard for Mother Nature, however ingenious she may be.
Perhaps the gecko takes advantage of tiny imperfections in the surface? Nope, they can climb a metal sheet smooth to the width of an atom/molecule.
What they appear to do is to take advantage of a fundamental force of nature which humans only discovered in the late nineteenth century, van der Waal's forces, which make up a small set of forces, eg co-valent bonding, which binds molecules together in compounds. The gecko's feet are covered with very fine hair. This hair has the most notorious split ends! Not content with that, the split ends have split ends. The cumulative effect of all the hairs, millions upon millions, is to bind the gecko to the molecular structure of the wall; but only just. The real trick comes when the gecko needs to disengage the foot from the wall!
The gecko 'unpeels' each toe on its foot by progressively bending the toe outwards and back on itself so that the muscular force required to 'unpeel' each section which is to be 'unbonded' is not overcome by the forces present; it, needless to say, does this extremely quickly. What is remarkable is that once the principle was understood, humans mimicked it and, yes, a rock climber climbed a veritcal brick wall using only outsized 'gecko hands' which utilised exactly the same principle as the gecko! Wonderful thing, science, don't you think?
This would, I think, be no more than an interesting curiosity were it not for one scientist's 'take' on biomimetics.
There is an enormous pressure on sub-Saharan communities due to the progressive desertification of those people who live at the desert's edge; how do you stop the desert's relentless march south? The proposal is to use the desert itsef. If you seed the sand dunes with a particular bacteria, and keep it fed, it will metabolise the sand into sandstone, thereby creating a 'wall'. Once the wall is created, you stop feeding the bacteria and the process stops. Such elegance. Such beauty! You can even make dwellings out of the sandstone wall you have created! It would be nice if everyone could agree to put this into place. A Great Wall across Africa to stem the march of the desert! A wall to rival that of China!
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