An electric fish is not something that you plug in. The term refers to species that use electrical emissions to map out their surrounding environment, track prey, communicate, or even zap enemy fish. If this sounds complicated it is because it is. Researchers are still trying to reverse engineer these amazing designs in electric fish. A key enabling technology at the molecular level is a machine known as the sodium channel. The sodium channel is mainly comprised of a rather large, four-domain membrane protein which has several operating modes used for controlling the flow of sodium ions in and out of the cell. The four domains span the cell membrane in a four-pack cluster which leaves a channel right down the middle. This isn't just any channel though. The peptide chains are arranged just so to create a channel that is incredibly selective for sodium ions. (And while potassium ions may have difficulty transiting the channel since they are larger, the potassium channel is, amazingly, equally effective at screening out the smaller sodium ions). And the sodium channel has a great many minor design variations allowing it to be used in different applications, and slightly differently in the same application.

Electric fish and sodium channels are not exactly the kind of products one thinks of as resulting from random mutations. Nonetheless, the Zakon paper authoritatively states that "Two groups of teleosts, the mormyriforms of Africa and the gymnotiforms of South America, have convergently evolved electric organs." And the paper concludes that certain evolutionary convergences occurred in the sodium channel genes. So there you have it—yet another objective journal paper dryly reporting yet another demonstration of evolution. Amazing, those electric organs really did, somehow, just evolve. In fact, this is all so run-of-the-mill that they evolved twice. If they can evolve once, then why not twice? Nature works in mysterious ways.

But wait. What exactly is the evidence for this? Just how did the authors arrive at this remarkable conclusion? It turns out that there really isn't any evidence, in particular, for the evolution of these electric organs or their sodium channels. The authors are working within a paradigm where evolution is taken for granted. When the authors conclude that the sodium channel genes in the two different lineages convergently evolved, they do not mean they have found evidence for evolution; rather, they mean that given the assumption that evolution is true, then certain convergences must have occurred in the sodium channel genes. Convergent evolution occurred in the sodium channel genes if evolution is true. The assumption of evolution is clear from the beginning:

We investigated whether the evolution of electric organs and electric signal diversity in two independently evolved lineages of electric fishes was accompanied by convergent changes on the molecular level.

The question was not if evolution occurred, but how it occurred. The bulk of the paper reports empirical findings that do not hinge on, nor support, evolution. The force-fitting of the results into the evolution paradigm is gratuitous. Of course this assumption of evolution is no surprise. But this means that such papers do not help evolution as is claimed. Piles and piles of papers that presuppose evolution and force-fit results do little to rescue evolution from its many evidential problems.