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Keywords: Science, Biology, Sex

Title: Power, Sex, Suicide: Mitochondria and the Meaning of Life

Author: Nick Lane

Publisher: Oxford University Press

ISBN: 0199205647

Reviewer: Paul Taylor

 

Yet again a popular science book shines an uplifting searchlight on old mysteries, compared to which the average New Wage [sic] booklet is a guttering aromatherapy candle.

The story of how organisms get and convert the energy needed to exist and persist would be interesting enough, but Lane derives a much larger significance: this is 'the story of life itself, not merely on Earth, but anywhere in the universe, for the morals of this story relate to the operating system that governs the evolution of all forms of complex life.'

Lane goes into some detail to explain how the energy transactions of the cell are a matter of pumping protons across cell membranes. Too many people blather on about 'life energy': this is the real thing, and the way that protons and electrons are shunted around has enormous consequences for what is possible and impossible for evolving organisms. For one thing, the mechanics of energy production relate to the size of the cell, and place an upper limit on how large bacteria can be, which is why they are microscopic and never comparable with multi-cellular organisms. The mitochondrion is at the heart of the story of our own evolution as large, complex organisms.

The origin of complex, multi-cellular life lies in a primordial, and by no means inevitable, symbiosis between two unicellular organisms two billion years ago. The implications of this union lead eventually to the pivotal role of the mitochondrion in the struggle against cancer: malfunctioning cells are forced to commit suicide by a process of programmed cell death. This role also takes us to the question of why how we age. Yet again, the mitochondrion is implicated in this fundamental fact of life, and Lane discusses the merits of the mitochondrial theory of ageing versus rival accounts. Age, Lane explains, 'is not measured in years, but in free-radical leakage'.

Energy production in the cell is a joint venture, carried out by mitochondria but genetically managed by themselves and the cell's nucleus. These sets of genes have to be precisely matched, and this matching is focussed by a specialization of inheritance: mitochondrial genes are passed on only by females. This arrangement is the fundamental reason why we have no more or less than two sexes.

This is an especially interesting and worthwhile science book, unfashionably not padded out with spurious 'human interest' stuff about what car the author drove to visit which laboratory under what weather conditions. Lane's next book is eagerly awaited.

Review © Paul Taylor. Site © London Book Review 2007. Published September 10 2007