Customer Reviews

Shaping Life: Genes, Embryos and Evolution (Darwinism Today series)

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I was prompted to write this after reading the review below from the New Mexico reader. He misses the point, not Maynard-Smith. This little book (45 pages)is based on a lecture given by Smith at the London School of Economics. The central theme of his lecture was to make the point that the two views in developmental biology i.e. dynamic-holistic view and the local-reductionist view are both important. But, he extends this thinking by suggesting that this dichotomy in biology is a pattern that exists in all aspects/spheres/disciplines in life. This is what I found so revealing. Gore Vs Bush could not be a better (current) example that comes to mind when reading the final chapter 5 - Reductionists to the right, Holists to the left.

Although I certainly enjoy most books and articles by Maynard Smith, this book was a tremendous disappointment. He argues against self-organization in biology in a very bad way. Instead of a good argument, one finds a subjective, totally biased and unscientific argument (what a splash pattern has to do with morphogenesis? no idea, really ... that's a funny picture but nothing to do with development). Still worse, Maynard Smith tries to "put down" previous and current work on development from the point of view of complexity by claiming that it has to do with some obscure disappointment with Marxism and with some feminist-like reasoning (? ). I find this strategy really unfair and not appropiate for a great scientist and writer such as Maynard Smith. I think that it is clear that selforganization is, **together with information and adaptation** a fundamental part of the understanding of life. In trying to ridiculize complexity and selforganization, the author is (perhaps uncounsciously) acting in a way not far from "scientific creationists".

In this lecture, J. M. Smith explains clearly the differences and the links between evolution, development, self-organization and reproduction.
Although there is a parallelism between the development changes that convert an egg into an adult and the evolutionary changes that converted single-celled ancestors into the existing array of multi-cellar animals and plants, these mechanism are entirely different: the development changes are not driven by natural selection. Development depends on genetic information accumulated during millions of years of evolution. The evolution of adult forms, however, depends on development changes in successive generations.

Changes in genes cause changes in morphology, but during the evolution, it is not the form (morphology), but the information that is conserved (the regulatory genes that act as signals inducing structures to develop at particular places).
Nonetheless, there is a necessary link between development and evolution. Development is modular and evolution proceeds by modifying the later development stages of a module. E.g., the embryo is successively divided into smaller and smaller regions, whose growth is to a degree autonomous. So, changes in one module become possible without the necessity to alter every part.

The basis of heredity is template (stamp) reproduction, not self-organizing structures, because the latter cannot ensure their own survival and reproduction.

This small book is a must read for all those interested in basic biology and evolution.