Sharkskin Makes a Good Model
Designs borrowed from animals are providing insights for improvements in techology
Roger Di Silvestro
The earliest ancestors of modern sharks first cruised the world's seas at least 450 million years, and many of today's species have been around a long, long time. The great white, for example, appeared about 60 million years ago, the mako maybe 100 million. The hammerhead is a relative newcomer, appearing in the fossil record about 25 million years in the past.
This great longevity means one thing: biological success. Species don't last that long if they aren't adaptable and highly successful in the game of life. New research from the University of South Florida suggests that one feature that has helped sharks survive is the hydrodynamic properties of their skin.
Learning from Sharkskin
Sharkskin bristles with scales that are, basically, just tiny versions of shark teeth. Amy Lang, of the University of Alabama, and her colleagues at the University of South Florida have found that the shape of these scales--wider at the top than at the bottom--causes water to flow over the skin in such a way that sharks can change direction while moving at top speed, as when chasing prey or fleeing enemies. In principle, Lang told Newswise, the science news service, the scales act like the dimples on golf balls, which help the balls to travel farther than they would if smooth.
Knowing how sharkskin works is not just a vague academic matter. The hydrodynamics discovered in sharkskin may be used to improve the design of metal coverings on aircraft, submarines and wind turbines.
Aping the techniques of mother nature is called "biomimickry," and it influeces everything from car design to heating systems in buildings to wind turbines and many other technologies. Take a look to see what technologists are learning from humpback whales, termites, yellow box fish and other creatures.