The remora, a type of sucking fish, is able to attach itself firmly to other sea creatures and then detach itself with ease and without harming the host. These abilities have intrigued researchers.

 Consider: The remora attaches itself to rays, sharks, turtles, whales, and other sea creatures, regardless of the texture of their skin or shell. The remora feeds on parasites and its host’s leftover food​—all the while enjoying a free ride and protection from predators. Researchers are studying the remora’s sucker, or suction disc, to see how it enables the fish to attach itself gently but firmly to a variety of surfaces.

 Remoras accompanying a whale shark

 The remora’s oval-shaped suction disc is located on the back of its head. The disc has a fleshy outer lip that forms a tight seal to maintain suction. Within the disc, rows of flaps have tiny, rigid spines. When the flaps are erect, the spines make contact with the host’s skin, creating friction. This combination of suction and friction keeps the remora firmly attached regardless of the host’s speed or sudden change in direction.

 Impressed by the remora’s adhesive disc, scientists have designed an artificial one. Their oval-shaped device can attach to a variety of surfaces. When the researchers tried to pull it off, it held on even against forces equal to hundreds of times the weight of the disc!

 Technology based on the remora’s sucker has many possible applications. These include use as research tags for sea creatures, use in deep ocean studies, and use as a means of attaching lights or tools to the underwater surfaces of bridges or ships.

 What do you think? Did the remora’s sucker evolve? Or was it designed?