The Reluctant Mr. Darwin - An Intimate Portrait of Charles Darwin and the Making of His Theory of Evolution by David Quammen
On the evening of July 1, 1858, six scientific papers were read to the Linnean Society in London. One of them was an idea independently discovered by two authors, Charles Darwin and Alfred Russel Wallace. Neither author was there; the young man, Wallace, was in New Guinea collecting insects, while the older man, Darwin, was moaning the death of his young son at home. The idea, natural selection, had nearly zero impact and in the annual address given the following year, the president of the society said the past year hadn't seen "any of those striking discoveries which at once revolutionize" science. That was the official birth, 150 years ago, of the single biggest idea in the biological sciences.
While the idea was presented to the world as the work of two independent authors, it is Darwin who is generally considered to be the father of the idea. Quammen shows why in this book. Darwin had first written about his idea in a letter in 1844 and had been concocting it at least for several years before. Quammen estimates the exact time as March of 1837 when Darwin knew natural selection existed, but not how. But he was deeply reluctant to talk about his ideas publicly because of their controversial nature, while at the same time amassing mountains of evidence in private. Wallace's letter to him forced his hand to publicly acknowledge the theory he had been working on for more than two decades.
It is well known that he had travelled to the Galapagos on the HMS Beagle and collected information and evidence that led to his theory of natural selection. What is less known, as Quammen explains, is the extent to which Darwin went to test his ideas through experiments. To verify if plant seeds could travel thousands of miles across the ocean and still germinate, he tested various seeds by immersing them in salt water for specified stretches of time. He was able to conclude that, for example, asparagus could float for 23 days when green and 85 days when dry. His experiments did not end with plants. They extended to animals and plants within animals. Yes, you will have to read the book if you want all the details.
David Quammen holds the Stegner Chair at the Department of History and Philosophy at the Montana State University. He has written several books about biology including The Song of the Dodo, which was awarded the John Burroughs Medal for natural history writing. Among other awards, he is a three time winner of the National Magazine Award.