Sinopsis
The decade immediately following publication of On the origin of species in 1859 to the eve of publication of Descent of man in 1871 was arguably the most intense and productive of Charles Darwin’s life. These were years in which the implications of the theories made public through Origin were explored and debated around the world, not only in the scientific community but in the public arena. Darwin, so far as his health would allow, set about countering criticisms with ever more detailed researches into complex mechanisms in organisms, teasing out how they could be explained as adaptations arising through the operation of natural selection. He also sought answers to the questions he knew Origin had not answered, in particular concerning the mechanisms of inheritance, and the evolutionary role of competition for sexual partners.
At the beginning of this period Darwin still intended to write the ‘Big Book’ on species of which Origin was only an abstract. As he resumed work on what had been intended as a single chapter on pigeon-breeding, however, it quickly became apparent that a detailed exposition of the production of domestic varieties of the
various animals he was researching would require a separate publication. In fact as his researches deepened and widened publications expanded out of one another like Russian dolls: a planned final chapter on human origins for Variation under domestication became another two-volume work, Descent of man and selection in relation to sex, and his work on the relationship of human and animal emotions outgrew the confines of Descent and was eventually published in 1872 as Expression of the emotions in man and animals.
The year 1859 had ended well for Darwin, who had been delighted at the news that the first edition of Origin had sold out on its first day, and was both relieved and deeply gratified by the generally positive initial reaction of his scientific colleagues. It was the more critical responses that were to set the tone for the next decade, however. Darwin’s major task in these years was to respond in detail, privately through letters and publicly through a rapid series of new editions and further publications, to both the specific scientific arguments raised against his theory and the philosophical qualms it inspired. A second, revised, edition of Origin was already out in January 1860, and the third substantially updated edition by the end of the year. By 1870,Darwin had published a fifth edition and was already gathering material for the sixth and final edition, published in 1872.
There was support for Darwin’s theories in a series of significant publications by others. To Darwin’s satisfaction, Henry Walter Bates’s work on protective mimicry invoked the mechanism of natural selection to explain the development of complex markings in insects. Thomas Henry Huxley’s Evidence as to man’s place in nature was published in 1863, as was Charles Lyell’s Antiquity of man, although this disappointed Darwin in its cautious stance. Darwin keenly followed the debates about his work. His ideas gained ground throughout the 1860s, as the numerous honorary fellowships and degrees bestowed upon him attest, but their acceptance was not achieved without struggle and was not wholesale. The annual award of the Royal Society of London’s Copley Medal became a battleground between Darwin’s supporters, such as Thomas Huxley and Hugh Falconer, and those members of the scientific establishment who, while respecting many of Darwin’s achievements, were anxious that the society not be seen to endorse the theories contained in Origin. Unsuccessful nominations in1862 and 1863 were followed by a narrow and controversial victory in 1864.
Critical reviews of Origin appeared abroad also, in particular in France, and many naturalists, such as the botanist Charles Naudin, although continuing to assist Darwin in his research, remained unconvinced by his arguments. In Germany, Darwin’s theories were spread by younger scholars such as Ernst Haeckel but resisted, to Darwin’s distress, by others. Darwin’s revisions to the fifth edition of Origin were made largely in direct response to criticisms such as those from the botanist Carl von Nägeli. One criticism that Darwin was very conscious could be levelled at the arguments in Origin was the absence of any explanation of how inheritance worked. He countered this with his theory of ‘pangenesis’, first privately circulated in 1865 but not published until 1868, when it appeared in Variation. Darwin postulated that ‘gemmules’ present in bodily fluids and transmitted fromparent to child had the ability to develop into different parts of organisms, but could lie dormant from generation to generation. Painfully conscious of the difficulty of supporting this theory with evidence, Darwin was disappointed, but not surprised, by its mixed reception. Darwin continued to be deeply interested in all questions concerning heredity, encouraging his cousin, Francis Galton, in his experiments transfusing blood in rabbits, and even suggesting that a question on cousin-marriage be inserted in the national census to gather data on the effects of inbreeding in humans.
Darwin had more success with the development of his theories concerning sexual selection. One of the arguments raised against natural selection was its inability to account for beauty in nature where that beauty apparently failed to offer any survival advantage. Much of Darwin’s correspondence in this period reflects his interest in gathering evidence of the importance of colour, sound, and smell in the attraction of sexual partners. He debated the relative importance of the mechanisms of sexual selection and natural selection in correspondence with Alfred Russel Wallace, who was inclined to attach less significance to the operation of sexual selection than was Darwin.
