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Around 30,000 years ago, while the sun was setting on the last Neanderthals in Spain, people in what is now Germany carved figurines from mammoth tusks. The known examples include a bird, sufficiently naturalistic as to suggest a cormorant, and a couple of figures that seem to combine human bodies with lions' heads. Deep in the prehistory of art, even as people taught themselves to represent natural creatures, they channelled their creativity into images of unnatural beings. We can only speculate on what these images meant, but we can hardly doubt that they meant a great deal.

The theme reappears in classical times: Daedalus the inventor designs the labyrinth that imprisons the Minotaur, product of an unnatural union between a bull and a woman that Daedalus helped engineer by luring the bull with an artificial cow. He makes wings of feathers and wax, which melts when his son Icarus flies too close to the sun, showing that trying to outsmart nature is a dangerous game. In the 1920s, the muscularly ironic scientist JBS Haldane took Daedalus as the title for an essay foreseeing a future in which only a minority of babies would be "born of woman"; most would be conceived and gestated in vitro.

He remarked that biological inventions were almost invariably regarded as perversions, "indecent and unnatural". This was indeed how in vitro fertilisation was greeted, as Philip Ball discusses at length in the second half of Unnatural, having set the scene by exploring the myths and fantasies that still shape contemporary debates about reproductive technologies.

Haldane, a biologist with a classics degree and an abiding interest in mythology, might have emitted a harrumph of approval for the breadth of Ball's classical reference, which extends to the neologism "anthropoeia": "making people". Labelling Ball a science writer sells his writing short, for its value lies above all in a range that dissolves the awkward silences between science and the larger culture of which it is part. JBS might also have acknowledged a productivity that echoes his own copious output. Although Unnatural reveals no hint of haste, it's only a year since the publication of Ball's previous and equally substantial book, The Music Instinct.

While the Minotaur was always scandalous, the ancient world did not inevitably recoil from human-animal forms - like the Egyptian gods that the prehistoric mammoth-ivory carvings uncannily prefigure. Ball argues that the idea of the unnatural takes a more decisive shape once deities coalesce into a single god, with sole responsibility for the natural order. Yet the sense of foreboding developed gradually. The possibility that alchemists might make artificial homunculi posed the conundrum of whether such beings would inherit original sin, but it was not seen as an affront to God.

The underlying question was whether an artificial being would have a soul: whether the clay could acquire spirit and thus become truly human. One way or another, artificial beings would be inferior. As Ball shows in a detailed examination of anthropoeic fiction, people in the age of science conceived all sorts of ways in which such hapless creations might be fatally flawed. In the defining vision of man-made man, the Frankenstein story in its many variations, the fatal flaw results from a combination of the Baron's crude technique and his hubris: Daedalus all over again.

During the 20th century the moral spotlight turned from the individual pioneer, the inventor-alchemist-scientist, to the system. Along came Aldous Huxley's Brave New World, a novel based on the same idea Haldane had sketched, in which the "hatcheries" of a totalitarian state have supplanted wombs. The unnatural now signified horror and dread; the stage was set for today's debates about IVF and other anthropoeic developments, actual and foretold. Although Mary Shelley wrote Frankenstein before the word "scientist" was coined, and Huxley wrote Brave New World in the bygone age of the great centrally-controlled states, their titles still dominate today's headlines.

Simultaneously fascinated and frustrated by the abiding sense of the unnatural that keeps Frankenstein on his throne, Ball is a little too ready to dismiss the possibility that future developments will have results that are not as ordinary as those of IVF. The feelings of adults for their juvenile clones would be different from those of identical twins for each other - and might be different from their feelings for children bearing half rather than all of their genes. But we won't be able to consider those possibilities properly until biomedical ethics are determined, as Ball gently suggests, by "informed and thoughtful living individuals and not by Sophocles, Goethe, Nathaniel Hawthorne, Mary Shelley or Aldous Huxley".