Nature’s self-cleaning marvels: Who did the Research & Development?
Butterfly wings, it has now been discovered, employ two of nature’s tricks to help keep themselves clean: the ‘shark skin effect’ and the ‘lotus effect’.1
On shark scales, microscopic riblets reduce friction as a shark slices through the water, and make it difficult for barnacles and other unwanted hitchhikers to grab hold. This phenomenon is the envy of engineers trying to overcome ‘biofouling’, which plagues shipping and other marine industries. It turns out that the tiny shingle-like scales on a butterfly’s wing similarly have an orderly arrangement of microgrooves and bumps, invisible to the naked eye. This feature both reduces in-flight drag and stops rainwater from pooling anywhere on the surface, preventing the build-up of debris and contaminants.
And this is helped by the butterfly wing’s lotus-like properties of low adhesion and superhydrophobicity (i.e. repelling water). The lotus has tiny bumps that trap air under any water droplets, which repels water from penetrating further.2 This means that water droplets “roll off effortlessly”, as described by Ohio State University’s Dr Bharat Bhushan, one of the researchers making this discovery of the combination of shark skin and lotus leaf features in butterfly wings (and in rice leaves, too).1 He and colleagues hope to see the fantastic properties of nature’s best self-cleaners copied in industry—but it will take quite some further research and development (R&D) yet.3
“We are investigating methods to fabricate rice leaf and butterfly wing-inspired films for applications requiring low drag, self-cleaning and anti-fouling,” Bhushan said.1 Such applications could range from marine anti-fouling to reducing the accumulation of microbes in medical tubing, thus lessening patients’ risk of infection.
This is certainly not the first time that design in nature has inspired industrial solutions. As Bhushan noted, “Living nature is full of engineering marvels, from the micro to the macro scale, that have inspired mankind for centuries.”1 Indeed so. The shark skin effect, for example, inspired low-drag ‘shark skin swimsuits’ that in 2009 were banned from Olympic competition because records were being smashed.4,5 But in reporting this latest discovery, LiveScience wrongly credited nature’s engineering marvels to nature itself:
“With 3.5 billion years of research and development under her belt, Mother Nature could be considered the world’s most experienced biological engineer. Sure, her methods may appear haphazard at times, but her track record of developing organisms that are exquisitely adapted to the tasks required of them is nothing short of amazing.”1
But the 3.5 billion years of time and nature’s mooted R&D are storytelling. No-one has ever observed nature’s ‘haphazard methods’ (ostensibly mutations and natural selection, according to evolutionary textbooks) produce the exquisite engineering design so prevalent in nature. If ‘she’ could ever6 marshal such blunt information-less instruments to produce information-rich, exquisite design, it really would be “nothing short of amazing”! (Miraculous, actually—but that’s not allowed!) Rather, these engineering marvels require a Marvellous Engineer. The Bible tells us Who that is, and when He did it—about 6,000 years ago, not billions.
References and notes
- Thompson, V., Engineers follow Mother Nature’s lead on keeping clean, livescience.com, 18 January 2013. Return to text.
- Barthlott, W., Neinhuis, C., Purity of the sacred lotus, or escape from contamination in biological surfaces, Planta 202(1):1–8, 1997; Ruokamo, J., Caution—slippery surface,creation.com/slippery, 13 October 2016. Return to text.
- Bixler, G. and Bharat Bhushan, Bioinspired rice leaf and butterfly wing surface structures combining shark skin and lotus effects, Soft Matter, 11 September 2012 | doi:10.1039/c2sm26655e. Return to text.
- Adams, D., The best of biomimicry: Here’s 7 brilliant examples of nature-inspired design, digitaltrends.com, 28 January 2017.Return to text.
- Sixty-six Olympic swimming records were broken at the 2008 Olympics, and 70 world swimming records throughout that whole year. West, M., By the skin of their suits, plus.maths.org, 4 April 2012.Return to text.
- See: Time—no friend of evolution, Creation 34(3):30–31, 2012;creation.com/time.Return to text.