Live Evolving: Molecules, Mind, and Meaning. Christian De Duve. (2003, Oxford University Press.) Hardback, £25, $39. 358 pages

Abstract

Live Evolving: Molecules, Mind, and Meaning. Christian De Duve. (2003, Oxford University Press.) Hardback, £25, $39. 358 pages. This book gives a very good overview of the topics related to the origin and evolution of life. De Duve joins the efforts of many researchers from different disciplines to explain the phenomenon of life in terms of chemistry and understand its evolution as a result of natural selection. He presents in a very clear way current evidence, theories, and open questions that have developed in recent decades due to advances in the sciences involved with the understanding of life. There have been other books discussing the origin and evolution of life (for a review comparing several of them, see [5]). Thus, many topics have been covered before. However, Life Evolving offers its own original angle. The content is very similar to that of De Duve’s previous books [2, 3], but the arguments have been enhanced and the ideas are better synthesized, incorporating the latest scientific advances. The book provides a very good introduction to molecular and cell biology (De Duve’s speciality). This should be particularly useful for non-biologists interested in ALife. Reading this book would be an advisable step before diving into specialized books such as [1] or [6]. Certainly, other aspects of evolution are discussed in the book, such as the evolution of humans, are well informed, but they give only a superficial introduction to current themes. This is not a weakness, for a book could be written on the topic of each chapter. I just want to point out that De Duve received a Nobel Prize in 1974 for his ‘‘discoveries concerning the structural and functional organization of the cell.’’ Thus, the parts of the book that deal with biology are stronger than those that deal with cognition. This must also be because our understanding of the cell is much more advanced than that of the brain. De Duve, having no problem in the lack of agreed definitions, reminds me of Isaac Newton. The story goes that Leibniz and Huygens asked Newton to define space, time, and motion, since they lie at the core of his physics. Newton boldly replied: ‘‘I do not need to define them, for they are well known to everybody.’’ In a similar spirit, De Duve uses the ‘‘general understanding’’ of debatable concepts such as mind, consciousness, and complexity. He does give a definition of life, though: ‘‘life is what is common to all living beings’’ (p. 8). Tautological as it might sound, in his context it makes perfect sense. He will not waste time discussing a definition of life, when the goal is to understand living systems. If and when this understanding becomes solid enough, the definition of life will be obvious. For the moment, De Duve discusses two complementary aspects of life: the chemical and the informational, which also could be called the structural and the functional. The first one deals with matter and energy that build life. However, these cannot explain by themselves the information processing carried out by living organisms. De Duve also notes that all known living beings are made of cells, so he traces the origins of life from the appearance of RNA, via DNA, to the origin of cells. He presents solid evidence to back up theories for each step that do not require any divine intervention, nor improbable results of chance. Life was bound to develop once the conditions were set for it. Once life appeared on Earth, De Duve traces its evolution to bacteria, eukaryotes, and multicellularity. Life evolves producing diversity, but also with a tendency to increase complexity. De Duve sets its current climax in humans. The argued complexity lies in the human brain, but probably measures of our DNA complexity, or number of cell types, could also put us at the top of the tree of life.