How to Make a Mermaid
- Life’s Solution: Inevitable Humans in a Lonely Universe by Simon Conway Morris
Cambridge, 464 pp, £18.95, September 2003, ISBN 0 521 82704 3
In a letter in the Times on 8 September 1809, W.M. Munro, a schoolmaster, described seeing a mermaid off the coast of Caithness. Walking along the shore of Sandside Bay, his attention was ‘arrested by the appearance of a figure resembling an unclothed human female, sitting upon a rock extending into the sea, and apparently in the action of combing its hair, which flowed around its shoulders’, and was ‘of a light brown colour’. ‘The head was shaded on the crown, the forehead round, the face plump, the cheeks ruddy, the eyes blue, the mouth and lips of a natural form, resembling those of a man.’ ‘The breasts and abdomen, the arms and fingers were of the size of a full-grown body of the human species.’
Societies which lacked a clear notion of the mechanisms of biological transformation intuited nonetheless, in their evocation of creatures with fabulous morphological complexities, that life is above all else about the generation and transmutation of form. Only as a result of profound transformation have the human mind and consciousness come into existence. Without the capacity for reflective thought and symbolic representation, we would still be red in tooth and claw, yet were they configured only slightly differently, our brains might not allow us to conceive such moral injunctions as thou shalt not kill.
Has life on Earth, the human race included, developed as it has simply as the result of an extraordinary sequence of chance evolutionary events, or was this development inevitable? Or, to put the question differently, if we stumbled across the inhabitants of another Earth-like planet in some distant galaxy, would our morphology appear as remarkable to them as a centaur’s does to us, or would it be reassuringly familiar? One way of settling the issue, suggested by the late Stephen Jay Gould, would be to wind the tape of life back to its origins, around four and a half billion years ago, then let the tape run again and see what happens. Ideally, we’d repeat this a few thousand times, and if then all of the reruns ended up producing humans, we could assert with reasonable confidence that humans are a more or less inexorable consequence of any evolutionary process beginning on Earth at the time of life’s origin.
The existence of alternative worlds, populated by creatures morphologically unlike ourselves, is a very real possibility. As for mythical creatures such as mermaids, we could allow that they might have come about as the result of natural evolutionary processes. Indeed, we might one day be able to build some from scratch. There are molecular biologists, among whom Sydney Brenner is probably the most vociferous, who espouse such a ‘constructional’ approach to biology. To build a mermaid from first principles one might begin by comparing the gene sequences of a fish with those of a female human. The trick would then be to determine whether the genes that generate a silver tail could somehow be integrated seamlessly with those that generate a female body, minus the legs. It’s possible that such a combination of features might turn out to be a logical impossibility: fusing the silver scaled tail with a female’s upper torso would be tricky, and it might be too difficult to manage the simultaneous construction of lungs and gills. On the other hand, the task might be so simple it could be completed in an afternoon.