Recently, scientists Christin, Weinreich (Brown University) and Besnard (Imperial College) discovered a fascinating side effect of evolution. Scientists have long known about something called convergent evolution, where species that evolve independently in different parts of the world end up looking remarkably similar. The tasmanian wolf (or thylacine, right) is a classic textbook case: it has remarkable similarities to North American and Eurasian wolves, yet it's actually a marsupial, related to the kangaroos.
The cause of convergent evolution is simple: a solution that works in one part of the world works everywhere. The traits that make wolves a successful predator in America also work for the thylacine in Australia.
Did you ever wonder why horses, cattle and antelopes and sparrows have eyes on the sides of their heads, while dogs, cats, owls and humans have eyes in the front? Simple: dogs, cats, owls and humans are predators, and they hunt horses, cattle, antelopes and sparrows. The prey animals need to have a 360-degree view because danger can be anywhere, while the predators need to see only the prey, and see it well. The stereoscopic front-facing eyes of predators converged (came about independently), as did the widely-spaced, 360-degree-view eyes of prey species.
Convergent evolution is a remarkable but well-understood part of the Theory of Evolution. But Christin et al reported on a remarkable evolutionary parallel that happens at the molecular level: in many cases the phenotype's convergent evolution (the eyes, teeth, organs or metabolic features that we can see) are accompanied by genetic convergent evolution. That is, the very same genes and gene sequences that control something in one species are found to control the same thing in another species!
That was quite surprising ... scientists had always assumed that when traits evolved separately and in complete isolation, there would be no genetic similarity. Yet there it was.
And that's where the trouble began. The Discovery Institute creationists seized on the word "surprising" in the scientists' article and started waving it around, like kids shouting "See! See! This proves it! It's a 'surprise' to these Darwinists, but if God was using his intelligence to design these animals, why it makes perfect sense for Him to re-use the same genes to do the same thing!"
In other words, "There's no mystery here, no important questions that science needs to answer. Why, it's just magic! God did it. Problem solved! We can all go home now." Or in their words,
An intelligent cause may reuse or redeploy the same module in different systems, without there necessarily being any material or physical connection between those systems. Even more simply, intelligent causes can generate identical patterns independently." (Paul Nelson and Jonathan Wells, "Homology in Biology," in Darwinism, Design, and Public Education, pg. 316) ... Might convergent genetic evolution actually be a pointer to intelligent design?Luckily for science and the advancement of human knowledge, Christin, Weinreich and Besnard aren't creationists, they are scientists, devoted to finding the truth whether it's surprising or not. They're willing to challenge their own assumptions, to admit they might be mistaken, and are open to learn a new truth when they find it.
And in fact, their "surprising" discovery turned out to strengthen, not weaken, the Theory of Evolution. The reason that the convergent evolution of phenotypes is accompanied by convergent evolution of genotypes is that the genome has a limited number of genes to work with, and the genes that can be used to "build" something in one species are probably the same genes that will work in another species.
Suppose you had a big box of tools – wrenches, screwdrivers, cutting torches, chisels, hammers, tongs, pliers and so forth, and you ask two different people to install a door. Would you be surprised that both selected a screwdriver to use to install the hinges on the door, and a hammer to tap the hingepins down? Would you say it was remarkable that neither of them used the cutting torch?
Of course not. But that's exactly what the creationists are claiming. More particularly, that's what author Casey Luskin ("an attorney with graduate degrees in both science and law," so he's trained in both trickery and science) is writing in his article, "Convergent Genetic Evolution: 'Surprising' Under Unguided Evolution, Expected Under Intelligent Design." I won't link to it because I refuse to give Google-cred to their web site, but I'm sure you know how to find it if you really want to read his drivel.
(Update: A reader at reddit.com pointed out that the original text used the term "coevolution" in a couple places. The correct term is "convergent evolution.")