Hypogean (cave, artesian) fishes have fascinated researchers even before they were described in the scientific literature in 1842. Since then, a number of scientists have used them to justify their own evolutionary ideas, from neo-Lamarckism to neo-Darwinism, from neutral evolution to selectionist approaches. Research in recent years has shown that these fishes are much more complex in their adaptations to the subterranean environment than previously believed: there are those with features expected from living in total darkness (complete blindness and depigmentation) and poor in nutrients...