the self-made tapestry pattern formation in nature jan 1999

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the self-made tapestry pattern formation in nature jan 1999

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[...]... intelligence The climate of the culture in molecular biology (although not, I think, the expressed belief of its individuals) is that, by understanding the roles of genes and the mutual interactions of the proteins derived from them, we will understand life This attitude finds expression, for instance, in the Human Genome Project, the international effort to map out every one of the 100 000 or so genes in the. .. anything seems possible You assume that nature has at its disposal an infinite palette, and that it dabbles at random with the choices, occasionally hitting on a winning formula and then building mostly minor variations on that theme: for fish, the torpedo-bodyand-fins theme, for land predators the four-legs-and-muscle idea To judge from the astonishing diversity of form apparent in fossils from the. .. brew can produce the surface patterns in Fig 1.3b, strikingly reminiscent in both shape and scale of the putative Martian fossils in Fig 1.1! What on earth sculpts these mineral bodies into such odd and apparently 'organic' forms? Fig 1.3 (a) Are these complex, patterned mineral structures the shells or skeletons of tiny organisms? On the contrary, they are the product of a purely synthetic chemical... principle in biological growth Insofar as I shall talk about biological form at all, the position I take is rather different I don't think we know very much yet about whether natural selection has the power to modify or suppress certain pattern- forming principles that occur in nature But I would suggest that, in the here and now, such principles undoubtedly existand do so in sharp distinction from the. .. uniformly in scale This, and the description above, help us to see what are the fundamental generating mechanisms of such a form Some things remain constant, for example the angular speed of the curve's tip, and the shape of the curve, while other things, for example the linear (tangential) speed of the tip, change in a welldefined way We can then generate a form like this by proposing that the deposition... know everything that is going on in the system we're looking at In other cases it may be because we know that some influences are of little significance, so that their inclusion would just make the equations harder to solve without altering the solutions very much Or again, it may be that certain influences are known to be important but we don't know how to include them, or how to solve the equations... Thompson's point was that it need not have been selectedit was inevitable Either the horn grew at the same rate all around the circumference, in which case it was straight, or there was this imbalance from one side to the other, giving a smooth curve It just did not make sense to invoke other shapes: nature' s palette contains just these two Even the more elaborate spiral form of a ram's horn need be only the. .. have an indication of what I mean when I use these words I cannot give either term a definition of mathematical rigour, however, nor can I always maintain a clear distinction between the two There is always an element of subjectivity in perceiving patterns On the whole I shall be concerned with patterns and forms in space, ones that we can see and perhaps touch But of course there are all sorts of patternsin... that patterning the worldshaping it into the forms of our needs and our dreamsis hard work It requires a dedication of effort and a skill at manipulation Each piece of the picture must be painstakingly put into place, whether by us or by nature This, we have come to believe, is the way to create any complex form So when they found complexity in nature, it is scarcely surprising that many theologians... broadens the horizons of 'black-box' biology, but there is no getting away from the fact that most of biology, particularly as a molecular Page 9 science, is hideously complicated, which, in distinction to complex, means that the particulars matter: leave out one part of the chain, and the whole thing falls apart In such a case, one gains rather than loses understanding as the magnification is increased . NASA.) precise in using this word), but not random. They have a kind of regularityevident, for instance, in the bilateral symmetry of our bodies or in the branching pattern of a treebut it is not the geometric. discovered in the nineteenth century, their origin has been disputed. The prevailing interpretation is that they represent the fossil remains of mat-like structures created by marine microorganisms. 276 Index 283 The plates section falls between pages 24 and 25 Page 1 1 Patterns The waves of the sea, the little ripples on the shore, the sweeping curve of the sandy bay between the headlands, the

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Mục lục

  • cover

  • 1. Patterns

  • 2. Bubbles

  • 3. Waves

  • 4. Bodies

  • 5. Branches

  • 6. Breakdowns

  • 7. Fluids

  • 8. Grains

  • 9. Communities

  • 10. Principles

  • Appendices

    • Appendix 1. Soap-Film Structures

    • Appendix 2. Oscillating Chemical Reactions

    • Appendix 3. Chemical Waves in the BZ Reaction

    • Appendix 4. Liesegang Bands

    • Appendix 5. The Hele-Shaw Cell

    • Appendix 6. Bénard Convection

    • Appendix 7. Grain Stratification in the Makse Cell

    • Bibliography

    • Index

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