| There are human analogies for almost everything in nature. Bats use sonar; the heart is a pump; the eye is a camera; natural selection is trial and error; genes are recipes; the brain is made from wires (known as axons) and switches (synapses); the hormonal system uses feedback control like an oil refinery; the immune system is a counter-espionage agency; bodily growth is like economic growth. And so, infinitely, on. Although some of these analogies can mislead, we are at least familiar with the kinds of techniques and technologies that Mother Nature employs to solve her various problems and achieve her ingenious designs. We have reinvented most of them ourselves in technological life. But now we must leave such comfortable terrain behind and step into the unknown. One of the most remarkable, beautiful and bizarre things that Mother Nature achieves without apparent difficulty is something for which we have no human analogy at all: the development of a human body from an undifferentiated blob called a fertilised egg. Imagine trying to design a piece of hardware (or software, for that matter) that could do something analogous to this feat. The Pentagon probably tried it, for all I know: 'Good Morning, Mandrake. Your job is to make a bomb that grows itself from a large blob of raw steel and a heap of explosive. You have an unlimited budget and one thousand of the best brains at your disposal in the New Mexico desert. I want to see a prototype by August. Rabbits can do it ten times a month. So it cannot be that hard. Any questions?' Without the handrail of analogy, it is difficult even to understand Mother Nature's feat. Something, somewhere must be imposing a pattern of increasing detail upon the egg as it grows and develops. There must be a plan. But unless we are to invoke divine intervention, that imposer of detail must be within the egg itself. And how can the egg make a pattern without starting with one? Little wonder that, in past centuries, there was a natural preference for theories of preformation, so that some people thought they saw within the human sperm a miniature homunculus of a man. Preformation, as even Aristotle spotted, merely postpones the problem, for how did the homunculus get its shape? Later theories were not much better, though… William Bateson came surprisingly close to the right answer when he conjectured that all organisms are made from an orderly series of parts or segments, and coined the term homeosis for it. And there was a vogue in the 1970s for explaining embryology by reference to increasingly sophisticated mathematical geometries, standing waves and other such arcana. Alas for mathematicians, nature's answer turns out, as ever, to be both simpler and much more easily understood, though the details are ferociously intricate. It all revolves around genes, which do indeed contain the plan in digital form. One large cluster of these developmental genes lies close to the middle of chromosome 12. The discovery of these genes and the elucidation of how they work is probably the greatest intellectual prize that modern genetics has won since the code itself was cracked. | — Matt Ridley, Genome - The Autobiography of a Species in 23 Chapters, Chapter 12 | Indexes/08 |
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Found that these genes and elucidation of how they work, may be the greatest wisdom award, won because of modern genetics of the code itself has been broken.
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