Friday, January 22, 2010

CHARLES DARWIN



  Charles Darwin was born on February 12th 1809 at Shrewsbury, Shropshire, England. 

He was the fifth child of Robert Waring Darwin and his wife Susannah; and the grandson of the physician-scientist Erasmus Darwin, and of the pottery magnate Josiah Wedgwood. His mother died in July 1817 when he was eight years old, and he was brought up by his sister, Caroline.


He was taught in accordance with a Greek language based classics curriculum at Shrewsbury from 1818-1825. Although he had not proved to have much academic aptitude at school in Shrewsbury he then went to Edinburgh to study medicine but did not make worthwhile progress. In his autobiography he mentions that;-

  "soon after this period I became convinced from various small circumstances that my Father would leave me property enough to subsist on with some comfort ... my belief was sufficient to check any strenuous effort to learn medicine".

  Another attempt at securing a gentleman's education and career was made, after his father had suggested the Church, by sending him to Christ's College, Cambridge, in 1827, to study theology with a view to becoming ordained as a clergyman.

  During his Cambridge years he did not immerse himself in Theological studies but rather fell in with a set who were keen on fox-hunting and game shooting. He also loved to collect plants, insects, and geological specimens, guided by his cousin William Darwin Fox, an entomologist. He developed a particular interest in collecting beetles, the rarer in species the better. His autobiography quotes one particular beetle hunt in detail:-

  "I will give a proof of my zeal: one day on tearing off some old bark, I saw two rare beetles and seized one in each hand; then I saw a third and new kind, which I could not bear to lose, so that I popped the one which I held in my right hand into my mouth. Alas it ejected some intensely acrid fluid, which burnt my tongue so that I was forced to spit the beetle out, which was lost, as well as the third one".

  His modest and untrained scientific inclinations were encouraged by Alan Sedgewick, a geologist and also by a botany professor, John Stevens Henslow, who was instrumental, despite heavy paternal opposition, in securing a unpaid place for Darwin as a naturalist on a long term scientific expedition that was to be made by HMS Beagle. In fact he only won parental consent to his joining the HMS Beagle after his uncle, Josiah Wedgewood II, spoke on his behalf. The intended career in the church had, at no time, been explicitly abandoned but his gaining the place on the HMS Beagle meant that he took another path in life.

  He was only twenty-two years old when the HMS Beagle left Devonport harbour on 27th December 1831. Also on board were three Tierra del Fuegan aboriginals who had acquired a veneer of westernisation since being brought to England three years previously - the Beagle was to repatriate them.

  During the subsequent five-year long expedition the Beagle visited amongst other places the Cape Verde Islands (where there was a volcano), Brazil, Argentina and Chile (where there was an earthquake). In the Galápagos Islands, off the coast of Ecuador, Darwin observed that each island supported its own form of tortoise, mockingbird, and finch; the various forms were closely related but differed in structure and eating habits from island to island. Both observations raised the question of possible links between distinct but similar species.

  The HMS Beagle visited many lands in the southern Pacific seas before returning to England via the southern Cape of Africa in an effective circumnavigation of the globe. It was to be October in 1836 before the expedition found its way back to the south coast of England. During the expedition Darwin had proved useful beyond his duties as a naturalist. As a young and very fit man he seems to have in more than one case accomplished tasks that saved the expedition from disaster.

  On setting out in 1831 Darwin's interests seems to have been primarily in Geology. In Chile the earthquake he had witnessed was accompanied by evident changes in the elevation of the land. He found fossils of sea life in the high Andes. His observations of the growth of Coral in the southern Pacific led him to recognise that the entire bed of the Ocean must be subject to significant raisings and fallings.

  Later during the HMS Beagle's voyage Darwin's interest seems to have become more focussed on the species of birds and animals he encountered. His five years of observation and adventure left him with much scope for speculation on the subject of the diversity of species. Prior to these times it had been assumed that species were of a fixed type. His thoughts began to increasingly challenge the assumption of the immutability of species.

  Darwin was greatly influenced by Thomas Malthus' Essay on the Principle of Population that suggested that populations would reproduce up to the limit set by their food supply and, at that limit, there would be a dire struggle for food. After reading Malthus' book Darwin's primary focus in his theorising of the diversity of species centered on the gaining of food - food being necessary both to survive and to breed.

  His speculations saw variations in type from a present species occuring randomly and those variations that favoured the winning of food would tend to ensure preferential survival and reproduction. There would not only be severe pressures within species towards the survival of efficient food gainers but there would also be severe pressures between species that were in competition for the same food sources. Through such speculations Darwin formulated what increasingly seemed to him to be a realistic theory of the evolutionary origin of species but, between academic caution and also due to the fact that he was the sort of person who shied away from involvement in controversy, he did not attempt to make his theory known to scientific colleagues let alone the wider public.

  Darwin became secretary of the Geological Society (1838-41). In January 1839 he was elected to membership of the Royal Society and also married his first cousin Emma Wedgewood (1808-96). They were later to become parents to ten children.

  From 1842 the family lived at Downe House, Downe, Kent. Darwin's life was that of a country gentleman of independent means among his gardens, conservatories, pigeons, and fowls. The practical knowledge he gained there through experimentation, especially in variation and interbreeding, proved invaluable. His private means enabled him to devote himself to science, by 1846 he had published several works on the geological and zoological discoveries of his voyage - works that placed him in the front rank of scientists.

  He suffered ill-health, which had set in to some extent even before his marriage, this meant that he adopted a retired lifestyle. It was not realized until after his death that he had suffered from Chagas disease, which he seems to have contracted during an onslaught of insect bites while in South America in 1835.

  We now come to the times of the presentation of the theory of the evolutionary origin of species before a wider public. Darwin had been intermittently adding to his theorisings - but to refer to a direct quotation from his autobiography:-

  Early in 1856 Lyell advised me to write out my views pretty fully, and I began at once to do so on a scale three or four times as extensive as that which was afterwards followed by my Origin of Species; yet it was only an abstract of the materials which I had collected, and I had got through about half the work on this scale. But my plans were overthrown, for early in the summer of 1858 Mr. Wallace, who was then in the Malay Archipelago, sent me an essay "On the tendency of varieties to depart indefinitely from the original type"; and this essay (arrived June 18th) contained exactly the same theory as mine. Mr. Wallace expressed the wish that if I thought well of his essay, I should send it to Lyell for perusal. The circumstances under which I consented at the request of Lyell and Hooker to allow an extract from my own M.S., together with a letter to Asa Grey dated September 5 1857, to be published at the same time with Wallace's essay, are given in the Journal of the Linnean Society 1858 p.45. I was at first very unwilling to consent, as I thought that Mr. Wallace might consider my doing so unjustifiable, for I did not then know how generous and noble was his disposition...

  ...Nevertheless our joint productions excited very little attention.

  This lack of an immediate reaction should perhaps be seen in a context where other scientists and thinkers had already suggested that life forms do change over time. A key difference about the new approach just presented was its inherent plausibility as providing a theoretical mechanism whereby changes in species, that had nothing to do with "God", were entirely to be expected. The case made was that there was a constant struggle for survival where those individuals who were "fittest" in terms of their ability to gain sufficient nourishment would survive and would reproductively generate a possibly adapted species.

  As this inherent plausibility became obvious to increasingly wider circles of people it meant that traditional beliefs and mind sets would inevitably come under serious challenge.

  The joint presention to the Linnean Society had taken place on 1st July 1858. Neither Darwin nor Alfred Russel Wallace was present on that historic occasion. Wallace was still in foreign parts whilst Darwin had the painful experience of being present at the funeral of one of his children - an eighteen-month-old son who had contracted scarlet fever.

  Following on from the presentation to the Linnean Society Darwin set to work to condense his vast mass of notes into the preparation of an article for inclusion in the journal of the Society. In the event a journal article seemed to give insufficient scope to relate all that he wished and this resulted in his assembling and shaping his great work, On the Origin of the Species by Means of Natural Selection, or the Preservation of Favoured races in the Struggle for Life, published in November 1859. This work, which was momentously challenging of numerous accepted beliefs and attitudes, sold out on its day of publication and later went through a number of editions. It was received througout Europe with the deepest interest and was often violently attacked because it did not agree with the account of creation given in the Book of Genesis, but eventually it succeeded in obtaining recognition from almost all biologists.

  Darwin's theory of the evolutionary origin of species was taken up by other persons who were more inclined to state controversial opinions than Darwin himself. Perhaps the most notable of these being Thomas Henry Huxley who was the first person to overtly claim that man must be a product of such evolutionary processes and was to become known as Darwin's Bulldog, a term that Huxley himself possibly coined, because of the resolute way in which he sought to promote Darwin's theory of the evolutionary origin of species.

  An overall effect of the ever wider spread of Darwinism was to make religious faith seem to be in many ways less credible and less reasonable. People's faith in Science meanwhile, despite the many profoundly unflattering connotations of Darwinism, was enhanced.

  Darwin continued to work at a series of supplemental treatises: The Fertilization of Orchids (1862), The Variation of Plants and Animals under Domestication (1867), and The Descent of Man and Selection in Relation to Sex (1871), which postulated that the human race derived from a hairy animal belonging to the great anthropoid group, and was related to the progenitors of the orang-utan, chimpanzee, and gorilla. In his 1871 work he also developed his important supplementary theory of sexual selection.

  Later works include The Expression of Emotions in Man and Animals (1872), Insectivorous Plants (1875), The Effects of Cross and Self Fertilization in the Vegetable Kingdom (1876), Different Forms of Flowers in Plants of the Same Species (1877), and The Formations of Vegetable Mould through the Action of Worms (1881).

  Charles Darwin was elected to the French Academy of Sciences in 1878.

  Darwin died at Downe on 19th April 1882 after a long illness. Following on from the suggestion of a group of members of parliament he was accorded the honour of being buried in Westminster Abbey. Several eminent scientists acted as pall bearers, numerous foreign dignitaries were in attendance.

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