Sharkskin actually increases drag

To clarify sharkskin's ability to reduce hydrodynamic drag (academically contested for the past 30 years), researchers recently conducted simulations on the ability of the small, tooth-like denticles that make up sharkskin to modify hydrodynamic flow with an unprecedented level of resolution. Far from easing the glide through the water, they found, the structures can actually increase drag by up to 50 percent.