June 25, 2017
By Damond Benningfield


Longhorn boxfish. Credit: public domain.

It may never serve as the mascot for a football team, but the longhorn boxfish still grabs your attention, because two pairs of horns extend from its body. One pair extends from the top of its head, although the horns go forward instead of sideways like those of the well-known cattle. And the other extends backwards from the bottom of its box-like body.

But there are more intriguing things about the longhorn boxfish than its horns: the way it feeds, its tough skin, and the deadly toxin it produces to ward off predators.

The fish is found around reefs in the Indian Ocean and the western Pacific. It grows up to about 20 inches long, and has colorful skin. It eats algae and other tiny organisms, including small fish, shellfish, and worms. It flushes out the larger prey by squirting a jet of water at the sandy bottom, blowing away their cover.

The longhorn is a slow swimmer, so it’s easily caught. But most predators stay away from it. That’s because it produces a neurotoxin when it’s startled. It excretes the material into a layer of mucus that coats its skin.

That skin might be its most interesting feature of all. It consists of a series of scales that are held together by connectors that are a bit like zippers. That structure makes the skin strong and tough, but lightweight and flexible. A few years ago, in fact, researchers said that engineers might learn a thing or two about making new materials by studying that skin -- something that’s much more interesting than the longhorn’s long horns.

This episode of Science and the SeaTM was made possible by Chuck Nash Auto Group of San Marcos, Texas.