The first listed species to make headlines after the Endangered Species Act was passed in 1973 was the snail darter, a three-inch fish that stood in the way of a massive dam on the Little Tennessee River. When the Supreme Court sided with the darter, Congress changed the rules. The dam was built, the river stopped flowing, and the snail darter went extinct on the Little Tennessee, though it survived in other waterways. A young Al Gore voted for...