Top positive review
A must-read, but it is only a hypothesis
on 20 April 2013
Lovelock's Gaia theory was written in the 1970s, but by now has become one of the most iconic environmental and scientific hypotheses, and for that reason alone, it is worth a read. Almost every debate on global warming, pollution and damage to biodiversity references this idea at some point, and with good reason, as it is an interesting idea that certainly has some valid scientific, as well as intuitive, basis. While a passing knowledge of biology and chemistry is useful for some of the more scientific chapters, it is not necessary in order to understand the ideas, and the text is well written and easy to read. It is a book that everyone could and should read, but that doesn't mean that it is without flaws.
Firstly, there is a difference between a hypothesis and a theory - a hypothesis is a proposed explanation, and only becomes a theory when its' arguments and anticipated effects are backed up by evidence. What this book contains is a hypothesis with some strong scientific evidence in parts, and some heavy speculation in other parts. The argument that the presence of life has maintained a different balance of elements and a different climate to what would occur without the existence of life is well explained and backed up with evidence, as are some specific examples around how certain systems regulate conditions such as the salinity of the ocean. However, in pursuit of the overall idea, I find that Lovelock starts to go a bit far, especially with the idea that life has in some way evolved to benefit the regulation of the planet. There is little evidence presented for this beyond the fact that it backs up his theory, and ideas such as the concept of corals building themselves into coral reefs to create evaporation lagoons with the intention of regulating the salt in the sea seem a bit too far-fetched.
This book should be praised for raising awareness of how inter-related life on earth is, and the indirect effects of our actions, but you may be surprised at some of the opinions on environmental issues in here. For example, Lovelock dismisses the threat to the ozone layer from CFCs as being insignificant (albeit partly due to the over-the-top doom-mongering at the time, rather than the modern worry that it will merely increase the chances of skin cancer).
Overall, it is a must-read, for the interesting ideas and for its' significance in modern thinking about the critical topics of the environment, but be warned that it is more of an expression of an idea than a fully explained thesis (I believe his book, 'The Ages of Gaia' provides a more scientific approach)