Blame it on Darwin
- Charles Darwin, Victorian Mythmaker by A.N. Wilson
John Murray, 438 pp, £25.00, September 2017, ISBN 978 1 4447 9488 5
When the 22-year-old Charles Darwin joined HMS Beagle in 1831 he took a copy of Paradise Lost with him, and over the next five years he read it many times, in Brazil, Patagonia, Tahiti, New Zealand, Australia and Mauritius. As the ship’s naturalist he sent commentaries and specimens back to colleagues in London, who soon came to see him not as a dilettante but an extremely acute observer. On his return he published an extensive Journal of Researches which showed that reading Milton by the light of a campfire had taught him how to write.
One evening, when we were about ten miles from the Bay of San Blas, vast numbers of butterflies, in bands or flocks of countless myriads, extended as far as the eye could range. Even by the aid of a telescope it was not possible to see a space free from butterflies. The seamen cried out ‘it was snowing butterflies,’ and such in fact was the appearance.
In 1845 the publisher John Murray reissued the book for a large public. Darwin became a literary celebrity.
Voyage of the Beagle (to use the title Murray gave it) is a vivid travelogue, but it also carries heavy theoretical freight. Darwin was struck by ‘how exactly the animals and plants in each region are adapted to each other’ and concluded that diverse life-forms should be understood not in isolation but on the basis of their reciprocal relations within what he called ‘the economy of nature’. He also noted that the world of living things is constantly changing, and suggested that specimens then assigned to separate species might belong to different branches of the same family, adapted over time to different ‘places’ in the natural economy. Having observed the damage visited on South America by ‘European animals run wild’ he knew that stable networks of mutual dependence are easily disrupted; but he also believed that new equilibria would establish themselves in due course. Thomas Malthus’s Essay on the Principle of Population (first published in 1798) had argued that human populations carry on growing until their needs exceed the supply of sustenance; and when Darwin read it in 1838 he extended the principle to all forms of life, suggesting that ‘the supply of food’ provides an automatic ‘check’ on population growth, ‘constantly preventing the too rapid increase of every organised being’.
Shortly afterwards Darwin settled to an unusually happy family life in Down House in Kent, with ‘a nice soft wife on a sofa’ and eventually seven surviving children, all of them eager, curious and rewarding. He was contemplating a ‘big book’ which would describe how the natural economies of the world have changed since the moment – perhaps hundreds of millions of years ago – when life emerged. His starting point was that progeny are not always exact replicas of their parents: they can differ from them, if only slightly, and pass the difference on to their offspring. He then suggested that when the difference happens to be advantageous, it will proliferate in succeeding generations. If you were religiously inclined you might attribute this built-in bias towards improvement to a benevolent providence, but Darwin had an alternative explanation: organisms that have an advantageous variation will be better at generating offspring, and will steadily out-breed their less fortunate cousins, driving them to extinction when the means of life become scarce.
The full text of this book review is only available to subscribers of the London Review of Books.