The Northern Clingfish is one of the weirdest animals I’ve ever seen. It has a suction cup on its belly that can tightly hold onto anything, no matter how rough and irregular the surface is. The cup’s grip is so strong that, if you had them on your hands, you would be able to climb a wet vertical rock wall—during a hurricane.
The fish uses its suction cup to rip apart mollusks from the rocks to which they are attached—and it works even underwater!
The cup uses a device that is similar in structure to the gecko: nano-filaments, tiny hairs that provide with the mechanism to attach to surfaces. But unlike the gecko, whose hairs provide with multiple points of contact for dry adhesion on vertical surfaces, the Northern Clingfish’s filaments provide with friction around the suction cup. The filaments are flexible and adapt to the structure of the uneven surface, making an air-tight wall that makes the seemingly impossibly strong suction possible.