The Swimming Tongue

Catfish have long been considered a delicacy in a number of cultures around the world, but scientific research has shown that they’re great tasting in more ways than one.

As bottom-dwelling fish that prefer to live in extremely muddy, murky waters, Catfish (order Siluriformes), have adapted to finding prey in the dark and therefore don't use their sense of vision to track down their food. Instead they take their sense of taste to the extreme. While the average human being has about 10,000 taste buds, catfish typically have more than ten times as many, with some large specimens boasting as many as 175,000 – and they aren’t just located in the fish’s mouth.

The entire body of the channel catfish (Ictalurus punctatus) for example, is entirely covered in taste buds, with the densest concentration - about 25 buds per square millimetre- found on the whiskery barbels around its mouth. These taste buds are incredibly sensitive and are able to detect certain proteins in water at concentrations as low as one part per 100 million.

Having such a huge concentration of hyper-sensitive taste buds increases the catfish’s ability to detect even trace amounts of food in the dark and murky waters of their home, so along with the thousands of buds along their body, the barbels allow the fish to not only taste when dinner is nearby but also hone in on its exact location even when visibility is poor.