When I first started diving over forty years ago in the Long Island Sound my first wet suit was a shark skin model named so because of all the little neoprene bumps that supposedly held the heat in better. I don’t know if it did but it did have a tendency to rip easily but did keep me warm in the cold water all year around. But unlike the real shark’s skin it didn’t help me swim any faster or more silently.
But real shark skin on the other hand doesn’t rip easily and will rough up human skin if rubbed against it from tail to head. The first shark I ever touched was a mako we caught in Montauk and when we lashed it to the boat I felt it’s skin and it was almost slippery going from head to tail but very rough going from tail to head. Before anyone gets in an up roar we ate the whole shark that were cut into steaks and grilled with butter and pepper. Quite good!
But the fact is that shark skin is amazing and is very similar to ray skin which is a close relative. In fact, way back before sand paper craftsmen used ray skin and shark skin to smooth wood. I don’t know how long it lasted but probably depended on the type of wood being sanded down.
The shark’s skin is actually made up of microscopic teeth that interlock and are referred to as dermal scales meaning skin scales. So when they swim through the water the scales do not create any drag thus letting the shark move effortlessly through the water. Most shark skin is grey in color regardless of the type of shark unless it’s a bottom feeder that needs to camouflage itself from it’s prey and other predators. The skin probably protects the shark due to the strength of the skin itself that comes from it’s thickness and design structure. In fact the dermal scales of a shark have a hardness equal to granite! Wow!
If humans had shark skin we would probably get a lot less injuries and minor cuts and abrasions would be a thing of the past. In fact, it would be like having on a mini chain mail suit of armor. Of course the interesting part would be that everyone would be basically the same color. Imagine that!
So next time you see a shark in an aquarium or in the ocean just take a look at their skin and see if you can see the dermal denticles which are unique to sharks and rays. Probably not but now you know they are there.