Friday, December 30, 2005


In the following paragraphs, Dawkins gets to the bottom of the "missing link" nonsense. Although in this example, he's talking about a continuous linkage of interbreeding species in space, he's making the point that evolution through time is exactly the same phenomena. No offspring of any parent is born so different that it could not breed with it's parent's generation, if such a thing were not taboo, but by incremental changes, eventually, each species reaches a point where it is so far removed from its origins that it would be unable to interbreed with it's ancestors if, indeed, it could go back in time and procreate. Further, usually so many species have disappeared in time, that the step by step changes in morphology, as exemplified by the morphing coloring of the herring gulls, cannot be clearly demarcated.

"In Britain the herring gull and the lesser black-backed gull are clearly distinct species. Anybody can tell the difference, most easily by the colour of the wing backs. Herring gulls have silver-gray wing backs, lesser black-backs, dark gray, almost black. More to the point, the birds themselves can tell the difference too, for they don't hybridize although they often meet and sometimes even breed alongside one another in mixed colonies. Zoologists therefore feel fully justified in giving them different names, Larus argentatus and Larus fuscus.

"But now here's the interesting observation, and the point of resemblance to the salamanders. If you follow the population of herring gulls westward to North America, then on around the world across Siberia and back to Europe again, you notice a curious fact. The 'herring gulls' as you move round the pole, gradually become less and less like herring gulls and more and more like lesser black-backed gulls until it turns out that our Western European lesser black-backed gulls actually are the other end of a ring-shaped continuum which started with herring gulls. At every stage around the ring, the birds are sufficiently similar to their immediate neighbors in the ring to interbreed with them. Until, that is, the ends of the continuum are reached, and the ring bites itself in the tail. The herring gull and the lesser black-backed gull in Europe never interbreed, although they are linked by a continuous series of interbreeding colleagues all the way round the other side of the world.

"Ring species like the salamanders and the gulls are only showing us in the spatial dimension something that must always happen in the time dimension. Suppose we humans, and the chimpanzees, were a ring species. It could have happened: a ring perhaps moving up one side of the Rift Valley, and down the other side, with two completely separate species coexisting at the southern end of the ring, but an unbroken continuum of interbreeding all the way up and back round the other side. If this were true, what would it do to our attitudes to other species? To apparent discontinuities generally?" —Richard Dawkins, THE ANCESTOR'S TALE, pp. 302-303


I recently checked out from the Spokane library a movie called, "The Grand Voyage", a film about the Moslem community in Europe. It reveals very clearly but ambivalently the split between the father and the son in an immigrant population. A young son is required by filial obedience to take his father to Mecca for his hadj. The son has a French girlfriend, a non-Moslem. He has a cell phone by which he communicates to his girl while he drives his father all the way around the Mediterranean, about 2,000 miles. It's an epic adventure, full of technical and human problems and arguments between the generations. It's comic and tragic both. To get some idea of the troubles between them—one night while the son is sleeping, his father leaves the cell phone behind so that his son may no longer call his French girlfriend. Cruel stuff. Both men hurt one another and the father is particularly uncommunicative. In another incident, they have lost their money and the son claims he can no longer eat eggs which is all they can afford, so the father trades a camera for a goat, but before they can slaughter the goat, it escapes and leaves them groaning with hunger, despair and rage. The climax is haunting and satisfying though the father and son still are not reconciled as one would hope even though they more clearly understand one another. Powerful stuff.

"A lie is an abomination unto the Lord and a very present help in time of trouble." —Adlai Stevenson [Looks like Bush and company have been reading Adlai's words.]

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