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Seven clues to the origin of life

1987; Wiley; Volume: 216; Issue: 1 Linguagem: Inglês

10.1016/0014-5793(87)80778-0

1873-3468

A. Trewavas,

Earth Systems and Cosmic Evolution

In this second book Cairns-Smith takes us through a well-trodden track in favour of his predilection for clay surfaces as effective primordial gene equivalents.The book is written apparently for a layman audience with frequent quotes from Conan Doyle's Sherlock Holmes to spice it up and give it the semblance of a thriller.The book is written very simply taking us through the knick-knacks of living systems, the difficulties of chemical evolution (a seen by Cairns-Smith) leading eventually to the necessity for clay surface structures and the requirements for carbon and nitrogen fixation in early metabolic events.The book is about 120 pages and is not overtaxing.However, I think in places trying to write a quasi-scientific text for putative laymen leads to the trap of oversimplification and of writing for an audience which may be non-existent for the book.Sentences such as 'What is the genetic material?It is called DNA' seem oddly stilted, sounding more like responses between priest and congregation in an affirmation of belief.Can't a layman assimilate that 'the genetic material is called DNA'?In talking about this topic however we come across 'mouse-traps', 'plug sockets', 'washing lines' and 'charm bracelets', as attempts at explanation.I wonder if anyone whose sole knowledge is at that level would with alacrity pick up the book to read it and if they did whether they would then find that language at all comprehensible.They might certainly end up with a strange view of cellular composition.All this in a chapter which the reader is encouraged to skip if he doesn't want to read it.However, to be fair the book is easy to read.In the chapter following the one called 'A Garden Path', an apt title since up it is where Cairns-Smith leads us, are arguments based on probability designed to discredit chemical evolution ideas.The argument runs like this.Assuming