“Sharks are almost perfectly evolved animals. We can learn a lot from studying them,” says Emory mathematician Alessandro Veneziani.
As an expert in fluid dynamics, Veneziani is particularly interested in the skin of sharks, which is not smooth – as might be expected for such a streamlined, efficient swimmer – but irregular and rough. “It’s counterintuitive,” Veneziani says. “One would expect that smooth skin would make a shark faster in the water but it’s not true, and there is a mathematical reason.”
The ridges, or riblets, on shark skin break up vortexes of water and reduce drag, a phenomena known as the riblet effect. Using differential equations, mathematicians have duplicated this effect so it can be applied to industry. Aircraft, for instance, are painted with special finishes to create a riblet effect.