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a vegetable affront to essentialism and the immutability of species. The wild cabbage, Brassica oleracea, is an undistinguished plant, vaguely like a weedy version of a domestic cabbage. In just a few centuries, wielding the fine and coarse chisels furnished by the toolbox of selective breeding techniques, horticulturalists have sculpted this rather nondescript plant into vegetables as strikingly different from each other and from the wild ancestor as broccoli, cauliflower, kohlrabi, kale, Brussels sprouts, spring greens, romanescu and, of course, the various kinds of vegetables that are still commonly called cabbage.
    
    
    Another familiar example is the sculpting of the wolf, Canis lupus, into the two hundred or so breeds of dog, Canis familiaris, that are recognized as separate by the UK Kennel Club, and the larger number of breeds that are genetically isolated from one another by the apartheid-like rules of pedigree breeding.
    Incidentally, the wild ancestor of all domestic dogs really does seem to be the wolf and only the wolf (although its domestication may have happened independently in different places around the world). Evolutionists haven’t always thought so. Darwin, along with many of his contemporaries, suspected that several species of wild canid, including wolves and jackals, had contributed ancestry to our domestic dogs. The Nobel Prize-winning Austrian ethologist Konrad Lorenz was of the same view. His Man Meets Dog, published in 1949, pushes the notion that domestic dog breeds fall into two main groups: those derived from jackals (the majority) and those derived from wolves (Lorenz’s own favourites, including Chows). Lorenz seems to have had no evidence at all for his dichotomy, other than the differences that he thought he saw in the personalities and characters of the breeds. The matter remained open until molecular genetic evidence came along to clinch it. There is now no doubt. Domestic dogs have no jackal ancestry at all. All breeds of dogs are modified wolves: not jackals, not coyotes and not foxes.
    The main point I want to draw out of domestication is its astonishing power to change the shape and behaviour of wild animals, and the speed with which it does so. Breeders are almost like modellers with endlessly malleable clay, or like sculptors wielding chisels, carving dogs or horses, or cows or cabbages, to their whim. I shall return to this image shortly. The relevance to natural evolution is that, although the selecting agent is man and not nature, the process is otherwise exactly the same. This is why Darwin gave so much prominence to domestication at the beginning of On the Origin of Species. Anybody can understand the principle of evolution by artificial selection. Natural selection is the same, with one minor detail changed.
    
    
    Strictly speaking, it is not the body of the dog or the cabbage that is carved by the breeder/sculptor but the gene pool of the breed or species. The idea of a gene pool is central to the body of knowledge and theory that goes under the name of the ‘Neo-Darwinian Synthesis’. Darwin himself knew nothing of it. It was not a part of his intellectual world, nor indeed were genes. He was aware, of course, that characteristics run in families; aware that offspring tend to resemble their parents and siblings; aware that particular characteristics of dogs and pigeons breed true. Heredity was a central plank of his theory of natural selection. But a gene pool is something else. The concept of a gene pool has meaning only in the light of Mendel’s law of the independent assortment of hereditary particles. Darwin never knew Mendel’s laws, for although Gregor Mendel, the Austrian monk who was the father of genetics, was Darwin’s contemporary, he published his findings in a German journal which Darwin never saw.
    A Mendelian gene is an all-or-nothing entity. When you were conceived, what you received from your father was not a substance, to be mixed with what you received