I recently read two contrasting books dealing with the broad sweep of evolution on Earth.

Andrew H. Knoll: Life on a Young Planet: the First Three Billion Years of Evolution on Earth, Princeton UP, 2003. Knoll is a paleontologist, and his book is especially strong on the evidence of fossils and geochemistry. It is weaker on the genetic approach to reconstructing phylogeny and the evolutionary timescale. Like many paleontologists, Knoll is inclined to play down the genetic evidence for divergence of major invertebrate phyla long before the ‘Cambrian Explosion’. But even if they left no fossils, they may just have been very small and soft-bodied - like much of the plankton today.

John Maynard Smith and Eors Szathmary: The Origins of Life: from the
Birth of Life to the Origins of Language, OUP, 1999, is a very different
kettle of poissons. It is primarily concerned with the theoretical problem of how increasingly complex systems can evolve, when they contain potentially conflicting elements. Maynard Smith is one of my heroes, but I didn’t read it when it first came out, because I assumed, based on the authors’ preface, that it was just a pop condensation of their earlier book The Major Transitions in Evolution. In a sense it is, but it is also much more than that. The whole book has been completely re-written and the arguments clarified. Much of the technical detail has been sacrificed, but it has also been updated to take account of new developments. For anyone seriously interested in evolutionary theory I think the books will complement each other, maybe reading Origins first and then working through Major Transitions a chapter at a time.

DAVID BURBRIDGE