Most new species are discovered, then described in the scientific literature with little fanfare, and most are then known only to a relatively small group of specialists. This was not the case with the snail darter (Percina tanasi), a small member of the freshwater fish family of perches, Percidae. The snail darter's discovery cast it in the limelight of a highly controversial, environmental battle over the impoundment of the Little Tennessee River by the Tellico Dam. Because its discovery coincided with the enactment of the Endangered Species Act, its only known habitat was the free-flowing channel of the Little Tennessee River, and it was perceived as a means of successfully challenging the completion of this Tennessee Valley Authority project.

Two ichthyologists at the University of Tennessee, Drs. David Etnier and Robert Stiles, discovered the snail darter in the Little Tennessee River in August of 1973. After catching...