By Jane Naberhuis, University of Illinois
As a researcher that works in a neonatal intensive care unit, I am required to get an annual flu shot. As the syringe was piercing my arm this year, I found myself thinking back to a paper I read recently about the structure of porcupine quills. North American porcupine quills have tiny, backward-facing barbs which dramatically reduce the force required for them to penetrate tissue. If harnessed correctly, this barbed design could translate to numerous applications in medicine where minimizing damage to surrounding tissue is important, such as use of a syringe or trochar. The link between something as unique as a porcupine quill and as everyday as a flu shot got me interested in other scientific and technological advances inspired by nature. Here are some of the more interesting connections I came across:
• Whale fins – fans, windmills, and surf boards
Adding bumpy ridges, similar to the tubercles found in a neat row on whale fins, has been shown to reduce drag, and to boost the power-harnessing capacity of windmills. Leave it to a 40 ton creature to devise an efficient way to travel through a fluid environment!
• Parasitic worm – skin graft attachment
Pomphorhynchus laevis uses its proboscis to pierce the flesh of its host with numerous microneedles, and then inflates its spiny head once inside the tissue to maintain its grip. Similarly, when tiny needles that expand on contact with water are attached to a skin graft, the graft stays in place more efficiently.
• Burr – Velcro
Remember those shoes you wore all through elementary school? After examining the burrs that clung to his dog following a hunting trip in the Alps, an engineer noticed the simple hook design that allowed them to stick so well to his dog’s fur. Velcro was patented eleven years later, in 1952,
• Gecko feet – adhesive
The numerous setae on a gecko’s feet allow it to scale smooth surfaces. Changing the direction of these setae allows the grip to be broken without any tearing or sticky residue. Adhesives using this type of technology could potentially replace surgical sutures and staples.
• Kingfisher – bullet train
As a high-speed train travels through a tunnel, air pressure builds and can produce a loud, painful thunderclap when the train emerges. Re-designing the front of the train to resemble the beak of a kingfisher, which are capable of diving into water making barely a ripple, eliminated this problem, reduced power use, and boosted speed.
• Shark skin – boat hulls, hospital and food-service surfaces, and athletic gear
Sharks manage to keep their skin free of algae and other organisms thanks to the dentricles coating their skin. These same dentricles also reduce drag, making them efficient swimmers. NASA has patterned the riblets used to reduce drag on planes, boats, and windmills after these dentricles, and dentricle-like structures are used to make surface materials for hospitals and other environments where cleanliness is crucial. Finally, at the Beijing Olympics in 2008, swimming events were dominated by competitors sporting specialized suits inspired by shark skin.
• Sunflower – solar power plants
The arrangement of heliostats, or mirrors, in a solar plant is crucial so that each heliostat faces the sun, but also does not block other heliostats from doing the same. Arranging heliostats in a manner similar to that spiral pattern found in a sunflower can help reduce the space required for a solar plant, as well as increase the amount of solar power collected by the panels.
This is just a sampling of everyday items whose design is inspired by the natural world. As the seasons change and you take the opportunity to enjoy the falling leaves and falling temperatures, take some time to think about these, and the other amazing scientific advances nature has inspired. If you’re feeling creative, perhaps you can dream up some new potential ways nature’s awesome designs could be utilized!
Choa WK, Ankruma JA, Guo D, et al. Microstructured barbs on the North American porcupine quill enable easy tissue penetration and difficult removal. PNAS 2012;109(52): 21289–21294.