Development of Darwin's Theory

Development of theory

Main article: Development of Darwin's theory

Fearing both scientific and religious criticism, Darwin spent decades developing his evolutionary theories largely in secret.

Darwin was now an eminent geologist in the scientific Ð"©lite of clerical naturalists, settled with a private income. He had a vast amount of work to do, writing up his findings and theories, and supervising the preparation of the multivolume Zoology, which would describe his collections. He was convinced of the truth of evolution, but for a long time had been aware that transmutation of species was associated with the crime of blasphemy as well as with Radical democratic agitators in Britain who were seeking to overthrow society; thus, publication risked ruining his reputation. He embarked on extensive experiments with plants and consultations with animal husbanders, including pigeon and pig breeders, trying to find soundly based answers to all the arguments he anticipated when he presented his theory in public.

When FitzRoy's account was published in May 1839, Darwin's Journal and Remarks was a great success. Later that year it was published on its own, becoming the bestseller nowadays known as The Voyage of the Beagle. In December 1839, as Emma's first pregnancy progressed, Darwin suffered more illness and accomplished little during the following year.

Darwin tried to explain his theory to close friends, but they were slow to show interest and thought that selection must need a divine selector. In 1842 the family moved to rural Down House to escape the pressures of London. Darwin formulated a short "Pencil Sketch" of his theory, and by 1844 had written a 240-page "Essay" that expanded his early ideas on natural selection. Darwin completed his third Geological book in 1846. Assisted by his friend, the young botanist Joseph Dalton Hooker, he embarked on a huge study of barnacles. In 1847, Hooker read the "Essay" and sent notes that provided Darwin with the calm critical feedback that he needed.

Darwin feared putting the theory out in an incomplete form, as his ideas about evolution would be highly controversial if any attention was paid to them at all. Other ideas about evolution Ð'-- especially the work of Jean-Baptiste Lamarck Ð'-- had been soundly dismissed by the British scientific community, and were associated with political radicalism. The anonymous publication of Vestiges of the Natural History of Creation in 1844 created another controversy over radicalism and evolution, and was roundly attacked by Darwin's friends who stressed that no reputable scientist would want to be associated with such ideas.

To try to deal with his illness, Darwin went to a spa in Malvern in 1849, and to his surprise found that the two months of water treatment helped. In his work on barnacles he found "homologies" that supported his theory by showing that slightly changed body parts could serve different functions to meet new conditions. Then his treasured daughter Annie fell ill, reawakening his fears that his illness might be hereditary. After a long series of crises, she died and Darwin lost all faith in a beneficent God.

He met the young freethinking naturalist Thomas Huxley who was to become a close friend and ally. Darwin's work on barnacles (Cirripedia) earned him the Royal Society's Royal Medal in 1853, establishing his reputation as a biologist. He completed this study in 1854 and turned his attention to his theory of species.

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Announcement and publication of theory

Charles Darwin, now an established geologist, was forced into early publication of his theory of natural selection.

Main article: Publication of Darwin's theory

Darwin found an answer to the problem of how genera forked in an analogy with industrial ideas of division of labour, with specialised varieties each finding their niche so that species could diverge. He experimented with seeds, testing their ability to survive sea-water to transfer species to isolated islands, and bred pigeons to test his ideas of natural selection being comparable to the "artificial selection" used by pigeon breeders.

In the spring of 1856, Lyell read a paper on the Introduction of species by Alfred Russel Wallace, a naturalist working in Borneo. Lyell urged Darwin to publish his theory to establish precedence. Despite illness, Darwin began a 3-volume book titled Natural Selection, getting specimens and information from naturalists including Wallace and Asa Gray. In December 1857 as Darwin worked on the book he received a letter from Wallace asking if it would delve into human origins. Sensitive to Lyell's fears, Darwin responded that "I think I shall avoid the whole subject, as so surrounded with prejudices, though I fully admit that it is the highest & most interesting problem for the naturalist". He encouraged Wallace's theorising, saying "without speculation there is no good & original observation". Darwin added that "I go much further than you". His manuscript reached 250,000 words, then on 18 June 1858 he received a paper in which Wallace described the evolutionary mechanism and requested him to send it on to Lyell. Darwin did so, shocked that he had been "forestalled". Though Wallace had not asked for publication, Darwin offered to send it to any journal that Wallace chose. He put matters in the hands of Lyell and Hooker. They agreed on a joint presentation at the Linnean Society on 1 July of On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection. Darwin's infant son died and he was unable to attend.

The initial announcement of the theory gained little immediate attention. It was mentioned briefly in a few small reviews, but to most people it seemed much the same as other varieties of evolutionary thought. For the next thirteen months Darwin struggled with ill health to produce an abstract of his "big book on species". Receiving constant encouragement from his scientific friends, Darwin finally finished his abstract and Lyell arranged to have it published by John Murray. The title was agreed as On the Origin of Species by Means of Natural Selection, and when the book went on sale to the trade on November 22, 1859, the stock of 1,250 copies was oversubscribed. At the time "Evolutionism" implied creation without divine intervention, and Darwin