On Gaia
Toby Tyrrell / Princeton / Hardback / £24.95 / ISBN: 978-0-6911-2158-1
Some 40 years ago, James Lovelock posed the Gaia hypothesis: that life itself keeps the planet in check via feedback mechanisms. In this book, Toby Tyrrell, a professor of earth systems at Southampton University, re-examines the hypothesis in the context of scientific research that has taken place in recent decades.
Tyrrell takes us through a number of natural systems; some are the same examples Lovelock used, but he also offers case studies, which appear to counter the Gaia hypothesis. Tyrrell offers no conclusion at this point, but rather a series of well-stated facts, which is both a strength and a weakness.
Although the book contains a scientifically correct set of descriptors to support and counter Gaia, it is rather turgid wading through the facts. That said, Tyrrell is scrupulous in addressing Lovelock’s assertions.
Eventually, the author provides a conclusion. Unlike other rebuttals of Gaia, which have been unfounded dismissals, Tyrrell considers all the information in the preceding chapters. He asserts that Gaia does not stand up to scrutiny, but does not dismiss entirely all of the hypothesis and brings together several arguments to conclude that co-evolution seems to be a more plausible hypothesis for how the Earth is maintained.
As Tyrrell acknowledges, his theory is not as grandiose as Gaia, but it is far more compelling. The conclusion is worth reading by itself if you are pushed for time, but for those who really want a good insight into Gaia in the context of natural systems, I would recommend reading the whole book.
Gillian Gibson, FIEMA CEnv, is an environmental scientist
