Reverse direction and it’s rough like sandpaper. Viewed under a microscope, shark skin is composed of ribbed, dragonesque scales layered over each other like shingles on a roof.

When he studied shark denticles under the electron microscope, he discovered why. "I said, "Wow!, That shark pattern, I'd never seen it before,'" he said.

A shark's skin is made up of thousands of armor-like scales, known as denticles. Now, humans are copying that pattern to fight the spread of bacteria.