Chimp business
By David Horton
03/02/2009 | Updated November 17, 2011
In this year of twin Darwin anniversaries, I find myself thinking of the great man (one of the few historical figures I would invite to a dinner party, but would he come, would he come?) even more often than in a normal year. I turn again to the Galapagos Islands, the place where, in a sense, all of the observations and ideas he had previously made on the voyage suddenly fell into place.
And I marvel again at the creationists and their stupidity which has such strong foundations in infinite ignorance. Here is a quote from a recent evolutionary thread - "I'm happy with the evolution of species within species, I'm convinced about mutation across kinds. Dog-Wolf I can cope with even if one is lupus and one canis since these words are our man-made nomenclature, Beetle-Man I find a bit too much of a leap." Leaving aside the originality of the "Beetle-Man" evolutionary link (I saw another that had Yeast-Human - whatever happened to good old primeval ooze?) this kind of sentiment erupts on every evolution post I have ever written or read. "It's all very well talking about antibiotic resistance in bacteria", someone will write, with that wonderful way they have of making a point made a million times before seem shiny and new (like Republicans and tax cuts), "but you show me where one species has ever become a different species". And they retire, having shown that Darwin fellow a thing or two about the real world.
We tend, I think, generous and empathetic to a fault, those of us on the reality-based side of the superstition curtain, to think that creationists have actually studied evolutionary theory, carefully considered it and then, having found what they believe to be one or two flaws, reluctantly and regretfully rejected it until such time as research resolves those questions. Just like the attitude of denialists to global warming.
But that sarcasm was unworthy of me, I know. Hard to resist though, when these people, whose brains scream maladaptation with every word they write, know, in fact, nothing of the evolutionary theories they are rejecting. When Darwin called his book "Origin of Species" he meant just that, an explanation of how new species came into being. His genius was to see, for the first time, that to answer this question you need to put together two apparently separate pieces of information. One everybody knew - species change over time. The second no one had previously spotted - if two populations of a species are separated geographically from each other both will continue to change over time and will eventually become so different that they will be unable to interbreed even if brought back together. This lack of reproductive potential between the two is how species are defined (they may still look very similar, and often do, a strange quirk for a "creator"), and it is important because once they can no longer breed with each other, the mutations that are accumulating in each, and the consequent natural selection processes, will continue quite independently. Each in turn can then give rise, in the right geographic circumstances, to two or more new species, and so ad infinitum.
The reason no one had spotted this obvious fact before is that on a large land mass subsequent movement of species, following their development, can obscure the fact that they were once separated (for example by the movements of glaciers, the rise and fall of sea level, the change of course of rivers, the rise of mountain ranges). What was needed was a world in microcosm, and that's what Darwin, the first naturalist to visit, found in the Galapagos group of islands. Here the development of species had occurred as populations became separated on islands too far apart for regular contact by small bird species (the famous finches). So here was a series of evolutionary events frozen in time (in a sense) and clearly visible. I have never, in the last 170 years, yet seen a creationist answer Darwin's very obvious question - why would a god go about creating a different species of finch on each island of a small group of islands? Incidentally the ability to see the process of speciation clearly in a group of islands was the reason why Alfred Wallace, working on islands in south east Asia, was also able to see how speciation worked, and went close to pipping Charles at the post.
So I suppose my question is how can creationists not be aware of this? How can they go on believing that "evolution" is merely the change within a species and not the origin of species? Do they really not know? Have they never had the wit to understand the simple proposition? Have they been deliberately misled by fundamentalist parents and teachers and preachers? Or are they refusing, dishonestly, to admit the obvious? They will grant change within a species, because changes in influenza (and other illnesses) alone make this hard to deny, but pretend that the question of separation of species has never been addressed (not just by Darwin and Wallace, but in the tens of thousands of cases of geographic speciation studied since by thousands of scientists). Because, and it is a very slippery slope indeed, once you admit that species originate in geographic separation, and then keep going their separate ways to become more or less different while maintaining clear evidence of their common origin, you have to come face to face with our Chimpanzee cousins. Once part of the same population as our ancestors but becoming separated by some chance geographic (perhaps climatic) event. And once you accept that relationship, that sense of a road not taken, can you really continue to say of the Chimpanzee "there but for the grace of god go I?" And can you really continue to talk nonsense about humans descending from beetles, or yeast, or primeval slime?
Many more attempts to reach across the curtain of superstition, bring the fundamentalists out into the light of reason, on The Watermelon Blog (which no longer exists.)
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David Horton is a writer and polymath.
"Darwin was the first to use data from nature to convince people that evolution is true, and his idea of natural selection was truly novel. It testifies to his genius that the concept of natural theology, accepted by most educated Westerners before 1859, was vanquished within only a few years by a single five-hundred-page book. On the Origin of Species turned the mysteries of life's diversity from mythology into genuine science." -- Jerry Coyne
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