Preface

This book is written as an addition both to Darwin's work and that of molecular biologists on evolution, so as to include views from the point of view of chemistry rather than just from our knowledge of the biology and genes of organisms. By concentrating on a wide range of chemical elements, not just those in traditional organic compounds, we show that there is a close relationship between the geological or environmental chemical changes from the formation of Earth and those of organisms from the time of their origin. These are considerations that Darwin or other scientists could not have explored until very recent times because sufficient analytical data were not available. They lead us to suggest that there is a combined geo- and biochemical evolution, that of an ecosystem, which has had a systematic chemical development. In this development the arrival of new very similar species is shown to be by random Darwinian competitive selection processes such that a huge variety of species coexist with only minor differences in chemistry and advantages, which is in agreement with previous studies. By way of contrast, we observe that on a large scale, groups of such species have special, different energy and chemical features and functions so that in fair part they support one another. It is more difficult to understand how they evolved and therefore we examine their energy and chemical development in detail. Overall we know that there is a cooperative evolution of a chemical system driven by capture of energy, mainly from the Sun, and its degradation, in which the chemistry of both the environment and organisms are facilitating intermediates. We will suggest that the overall drive of the whole joint system is to optimise the rate of this energy degradation. The living part of the system, the organisms, is under the influence of inevitable inorganic environmental change which moves rapidly to equilibrium conditions, though much of it was forced by the different chemicals added to it by organisms at different times. We are also able to explore some ways in which the organic chemicals of organisms evolved. Such evolution was dependent on the inevitably changing environment for all its chemicals and therefore much novel organic chemistry followed a determined path. We recognise that as complexity of the chemistry of organisms increased, the organisms had to become part of a cooperative overall activity and could not remain as isolated species. Prokaryotes and bacteria managed by long-distance exchange between different cells; eukaryotes evolved by incorporating some bacteria – the organelles. The eukaryotes also had increasing numbers of other compartments found in both animals and plants. Later division of essential activities was by direct combination of differentiated cells and by further different forms of symbiosis. Only in the last chapter do we attempt to make a connection between the changing chemistry of organisms with the coded molecules, DNA, of each cell which have to exist to explain reproduction.

This book has to encompass the full spectrum of chemistry, from the extreme of Earth Sciences to those of Biological Sciences. No author can claim to cover all these disciplines to an appropriate depth. The authors of this book apologise for misjudgements of any particular topics and trust that readers will inform them of any errors.