Oxygen: the Molecule that made the World

Oxygen: the Molecule that made the WorldThe word 'enthusiast' has changed in meaning over the years.In the eighteenth century, it was not wholly complimentary: 'One who vainly imagines a private revelation; one of a hot imagination or violent passions; one of elevated fancy or exalted ideas' wrote Dr Johnson in his Dictionary of 1755.Addison noted with distaste that certain religious sects displayed 'strong Tinctures of Enthusiasm'.Nick Lane is clearly an enthusiast in a modern, non-pejorative sense.What other description can you apply to an author who sets out to write about '. . .life, death and oxygen: about how and why life produced and adapted to oxygen; about the evolutionary past and future of life on Earth; about energy and health, disease and death, sex and regeneration; and about ourselves' (p.2)?All this in a book 1 that is '. . .not a catalogue of dry facts . . .rather, like science itself, it is full of quirks, experiments, oddities, speculations, hypotheses and predictions' (pp.[13][14].These two quotations are useful in that they at once indicate the ambitious scale of the book and some of the difficulties the reader may encounter.Paraphrasing and grossly reducing Lane's own aims, we may say that he pursues three huge topics-the formation of an oxygenated atmosphere, the emergence of oxygendependent organisms, and the complementary hazards of oxygen toxicity.About one-third of the way through the book, chapter five, readers may be disconcerted to find themselves no further than the carboniferous period; but by chapter fifteen they will have found extended discussions of the biochemical, biological and pathological aspects of free radicals.Much emphasis is given to ageing and to agerelated diseases.Lane necessarily draws on information from a wide range of disciplines: a list including geology, geochemistry, palaeontology, biochemistry, zoology, genetics, molecular biology and medicine is representative but by no means complete.In any one of them, experimentally described data will (self-evidently) vary enormously in terms of the methodologies by which they are derived and the extent to which they can be validated and legitimately extrapolated.Certain findings, sometimes obtained from restricted and highly contrived conditions, may prove to be compatible with other observations and come to form an evidential basis for plausible, testable theories.Cumulative weight of evidence is a familiar notion; but so, too, is the recognition of anomalies which (though securely based) do not fit into accepted schemata and may indeed eventually lead to their modification or rejection.This state of permanently