Blind Fish Lead the Blind
Imagine miniature subs that can negotiate tight spaces or murky waters in the dark. Meet Snookie: a device created by researchers at the University of Technology Munich, who took their inspiration from blind cave fish.
The report on Live Science says that the blind Mexican cave fish Astyanax mexicanus is born with eyes that degenerate in adulthood, because eyes are of no use in the darkness of its cave habitat. Instead, the fish has a heightened sensitivity along its lateral line – a sense organ running from gill to tail that contains “hundreds to thousands of fine sensory hairs located on the scales or in tiny ducts beneath the skin.” Like the inner ear, the article says, the lateral line can pick up tiny variations in pressure and water flow that give it an exquisite sense of its surroundings. An African frog uses its lateral line to distinguish between edible and inedible insects purely on the vibrations they set up in the water.
So why not build a similar organ on robotic submarines? That’s what the team at University of Technology Munich did. Their “Snookie” swimming robot “can orient itself in murky waters with an artificial sensory organ inspired by the lateral line.” It had to be small enough to get into tight places but large enough to hold all the electronics. They found out that getting a sensory picture from pressure vibrations is harder than with light, but it’s good enough to report pressure changes less than one percent in a tenth of a second from obstacles and movements a hand’s breadth in front and on either side.
Who would have thought that blind cave fish would inspire robots? One day, Snookie’s descendents could inspect sewer lines, investigate shipwrecks, locate flight recorders, assist scuba divers, and much more. They might even swim in swarms and explore environments with teamwork. Undoubtedly their descendents will be products of intelligent design – not mutation and selection.
This fun and interesting story needs one clarification; the fish’s lateral line did not “emerge” by evolution as if stimulated from its dark cave environment. It was already there, as it is in most fish and amphibians. They have what they need; landlubbers have what they need – by design that we can study and imitate.