http://www.youtube.com/watch?v=VxSs1kGZQqc&feature=player_embedded
Perhaps the most far-out concept in The Gecko’s Foot is the Micro Air Vehicle (MAV). This is a robot fly or bee intended to fly into restricted spaces and relay video back to control. The MAV would use flapping flight and have to be self-orientating. I was worried about this one. The idea was intrinsically appealing and, given the progress of chip miniaturization and micro-fabrication, I didn’t doubt that it was possible. But for a few years nothing much seemed to happen. But now papers are coming thick and fast and the first such robot fly, from Robert J Wood’s lab flew this year. Another team has tried to trump this by attaching a chip to a beetle which enables human control of the beetle’s movements. Which will triumph – the hi-jacked insect or the fully synthetic robot? Wait and see. Meanwhile, you can see how Wood’s team fabricate the Harvard Monolithic Bee:
http://www.youtube.com/watch?v=VxSs1kGZQqc&feature=player_embedded _ When I wrote The Gecko’s Foot, published in 2005, I took a punt on a handful of new technologies derived from nature that seemed to me the most promising. I confess that I didn’t fully realise just how long the lead time could be in bringing such techniques to fruition. But six years on, most of them are burgeoning and beginning to fulfil their promise. It seems a good time to check them, one by one.
Far and way the lead technology is the Lotus Effect: self-cleaning surfaces that are either superhydrophobic or superhydrophilic, inspired by the age-old symbol of purity, the sacred lots plant. Many labs across the world have contributed to this and there are now many products on the market with self-cleaning properties. St Pancras station in London now has a roof of self-cleaning glass. The latest twist is to the create surface that are omniphobic – meaning equally repellent to oil and water. This is quite hard to do, oil and water having notoriously different wetting properties. But this now seems possible by mimicking the pitcher plant, which lives by luring insects into its pitcher: the walls are intensely slippery and once in, nothing gets out. You can read all about it in Nature, 2011, 477, p. 443. Earth, air, fire and water were the 4 Greek elements. We know better now: there are 92 natural chemical elements and a few more that can be made in nuclear reactors; there are, according to Chemical Abstracts 55 million known chemical compounds and this total grows at a frightening rate.
But perhaps we should think more in terms of two of those Greek “elements”: air and water. Many vital materials for hi-tech industry are in short supply but air and water are massively abundant. Wouldn’t it be wonderful if we could make mouldable solid materials from these primal (but not elemental) substances? An obvious pipedream but thanks to nanotechnology it is coming true. It has been known for along time that the paradoxical way to make strong material is to leave much of the solid stuff out. The honeycomb core of composite panels is strong and exceptionally light. What this idea tends towards is the solid foam and this was realised a long time ago in the form of aerogels. The aerogel was invented as long ago as 1929. It is a foam from which the water has been withdrawn, leaving the structure intact and replacing the water with air. The most common material is silica, which is also used by nature in the intricate Buckminster Fuller-like structures of the tiny marine radiolarians. Aerogels have been much developed since their invention but they are still fabulously expensive, Their main applications have been in space technology. What is special about them? Aerogels are the lowest density materials known. They are so wispy that the name “solid smoke” has been coined for them. They are almost transparent but not quite, having an eerie bluish cast They are tough in compression but above all they are the most efficient insulators on earth. A crayon placed on aerogel cannot be melted by a Bunsen burner placed underneath. If aerogels could be made more cheaply they would revolutionise insulation technology, especially in the home. Various figures are quoted for the proportion of air in an aerogel, but it is reliably over 90%; the highest figure I’ve seen is 99.8%. Can the same be done with water? Yes: a Japanese team has developed mouldable plastics consisting of 98% water. The secret of both the air and water substances is dendritic molecules. These are large many branched molecules in which the endless ramifications provide a strong network which encloses the air or water. The idea seems entirely counter-intuitive, like most nanotechnology, but both aerogels and aqua plastic pass the Dr Johnson test of reality: they are solid – you can stub your toe on them. And so much more. With thanks to Dan O’Dwyer for reminding me about the properties of aerogels. Q. Wang, et al. High–Water–Content Mouldable Hydrogels by Mixing Clay and Dendritic Molecular Binder, Nature 2010, 463, 339. Termites have figured in bio-inspiration for their air-conditioned nests which have provided a model for some architects. They now potentially have a much more widespread use for their ability to digest wood. To produce biofuels requires the breakdown of lignin and cellulose to sugars. Termites digest wood using enzymes and the August Materials World reports work by a team at Purdue University, West Lafayette, USA, led by Michael Scharf, on genetically engineered termite enzymes. At present, digestion of woody tissue for biofuels requires energy: termite enzymes introduce the possiblity of achieving digestion at ambient temperatures. So far a lab process rather than industrial chemistry, termite-enzyme digestion looks like a very promising technique for biofuels and organic feedstocks.
Photosynthesis is the most important chemical reaction on the planet. It powers all the living energy systems on earth, allowing plants to grow, animals to move and cycles of weather to support life. It produces the biomass needed to feed the animals (including us) and also provides us with all of our materials, bar minerals and metals. Finally, through fossil biomass it provides most of our transport, home and industrial energy.
The pressure on natural photosynthetic systems and exhaustion of fossil stocks make direct mimicking of photosynthesis a key goal. The reaction is purely electrochemical- there is no vitalist living magic about it, so we ought to be able to copy it. There are many current strategies but the most promising and imaginative is Carlo Montemagno’s. He has harnessed modules from three totally separate living systems – the universal ATP energy motor from bacteria; the light harvesting pigment bacteriorhodopsin from Halbacterium salinarium and a remarkable foam from the Tungara frog. Lest you think that since these are all from living systems, life is required, Montemagno has created the same effect using block copolymers instead of the foam. The advantage of the foam is that one can now envisage huge vats of foam photosynthesis plants, with the glucose being drawn off for further processing. These separate systems work happily together, with light and simple phosphates, to build biomass. Industrialised, these light-harvesting biomass-creating foams could operate in barren regions, leaving fertile land for food production. In March, Montemagno’s foam won the $50,000 Earth Award. It is high time we learnt this trick. Rather shamingly,another animal has beaten us to the goal of exploiting photosynthesis. The sea slug Elysia chlorotica feeds on algae and it has evolved to incorporate some of the algal genes, allowing it to live without feeding. The slugs are appropriately green in colour. . We don’t have to turn our own bodies green but the slugs show that the plants’ trick can be harnessed outside the plant context. Perhaps we should pension off the world “sluggish” and get ourselves up to pace with light harvesting. Richard Hammond's Invisible Worlds on BBC1 last night featured bioinspiration. Three key subjcets - the Lotus Effect, spider silk and gecko adhesion - were featured. All first appeared in The Gecko's Foot (2005), still the only popular science book on the subject. Bioinspiration is set to be a key element in the new technologies that will fill the gap left by industrial collapse and the banking implosion.
Banksy versus Bristol Museum is an obvious media and popular triumph but many seem to want to play down its artistic significance. The show is actually full of surprises and paints Banksy in a new light: the heir to a line that includes Picasso, Sir Ernst Gombrich and the study of mimicry in nature.
How so? One room in the show contains pieces that Banksy could never have mounted on the street: animatronic creatures in caged installations. These include a rabbit surrounded by make up gear admiring herself in front of a mirror and a chimpanzee artist rocking his head, closing one eye after the other as he sizes up the conventional landscape he is painting. These make telling points about human vanity and they also show how easily an impression of life can be created by a few simple movements: if it twitches it must be alive. Then there is the animated processed food. Chicken nuggets hatched from eggs are feeding; a salami squirms as if to escape its plastic casing; a mustard-coated sausage in a hot dog sips water. But the most amazing of these living processed food sculptures is the salami in which the thread that tied it to a hanging string is draped to look like whiskers. The cartoon minimalism of this creature is stunning: a craning salami head and a wispy string and, hey presto, it is a walrus. But – the other stroke of genius – the tail of this writhing walrus/salami has already been diced and sliced several times. It is impossible to look at Banksy’s salami without thinking of the assemblages Picasso created around 1948-51. Foraging for suggestive junk around rubbish tips in Vallauris, he created a series of sculptures, including a Little Owl who struts on rusty screws for feet, a bull’s horns made from a bike handlebar, and a baboon’s head from two toy cars, placed wheel to wheel. Whether Banksy was thinking of Picasso’s assemblages when he created these living-food pieces I don’t know but he was certainly thinking of Picasso when he mounted the show. On a plaque inscription he quotes Picasso as saying that “Bad artists copy; great artists steal”, scratches out the attribution to Picasso, and substitutes his own name. There is no evidence Picasso ever said this, although one feels he ought to have. The authentic quote is from T. S. Eliot (“immature poets imitate; mature poets steal”) but in essence I’m sure that Eliot, Picasso and Banksy are at one on this. In one piece Banksy surpasses Picasso by using equipment unknown in the 1950s. The contemporary hi-tech equivalent of Picasso’s Little Owl is the CCTV family of a mother and two chicks. Perched on their poles over the motorways, CCTV cameras already look like storks; in the Banksy, a mother CCTV gazes down solicitously on her two tiny offspring. Her head roves back and forth over them; the agitated babies crane up to her, jiggling their beaks for food, as fledglings do. The wit and resonance of this piece – its punning on ideas of surveillance, protection, and maternal care v. Big Brother intrusion – is a triumph. Such punning visual suggestions were of deep interest to the art historian Sir Ernst Gombrich, who showed how a thread of visual punning ran through cartooning (Banksy is, much of the time, a cartoonist), and advertising, as well as fine art. He highlighted the punning of natural forms and human gestures, as in an 18th century French cartoon which saw the character of Louis Philippe’s face in a pear (a secondary meaning of “poire” in French is fathead, so the cartoon is both visually insulting, in emphasizing the flabby jowly features of the King and a verbal insult). Gombrich commented: “Thus a play on words and a visual joke were happily combined”. Gombrich also noted that nature has equivalents for artistic styles; leaf mimicry is naturalistic but a butterfly’s eyespots “represent, if you like, the Expressionist style of nature”, meaning that the eyespot is a symbolic warning gesture that doesn’t copy anything. For millions of years before Picasso and Banksy appeared on the scene, creatures have been masquerading as a different kind of thing entirely, either camouflaging themselves against the background like the peppered moth (pale and peppered against lichen in the country; black against soot in the city), or mimicking the form of a stone, a leaf or another creature, as the harmless kingsnakes do, donning the red, yellow and black banding of the toxic coral snakes. In his two-dimensional work Banksy is expert at pointing up the sad contradictions of human existence: the gross Western tourist couple, grinning inanely and self-admiringly into their camera phones as they are pulled in a rickshaw by a waif of an Asian boy; another waif, lost in a blasted wilderness, sporting an “I Don’t Like Mondays” T shirt. In Banksy’s “menagerie room” at Bristol, in three dimensions, he ranges across the world of animals/food and machines to show that our vaunted gestures are not so grand and that vitality and significant form reside in all creation. Picasso would be applauding and so, I think, would Darwin, who was the first to note the similarity between animal and human expressions.
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AuthorI'm a writer whose interests include the biological revolution happening now, the relationship between art and science, jazz, and the state of the planet Archives
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