Saturday, 25 January 2014

Charles Darwin

Three quarter length studio photo showing Darwin's characteristic large forehead and bushy eyebrows with deep set eyes, pug nose and mouth set in a determined look. He is bald on top, with dark hair and long side whiskers but no beard or moustache. His jacket is dark, with very wide lapels, and his trousers are a light check pattern. His shirt has an upright wing collar, and his cravat is tucked into his waistcoat which is a light fine checked pattern.Charles Robert Darwin, FRS (12 February 1809 – 19 April 1882) was an English naturalistand geologist, best known for his contributions to evolutionary theory. He established that all species of life have descended over time from common ancestors, and in a joint publication with Alfred Russel Wallace introduced his scientific theory that this branching pattern of evolution resulted from a process that he called natural selection, in which thestruggle for existence has a similar effect to the artificial selection involved in selective breeding.
Darwin published his theory of evolution with compelling evidence in his 1859 book On the Origin of Species, overcoming scientific rejection of earlier concepts of transmutation of species. By the 1870s the scientific community and much of the general public had accepted evolution as a fact. However, many favoured competing explanations and it was not until the emergence of the modern evolutionary synthesis from the 1930s to the 1950s that a broad consensus developed in which natural selection was the basic mechanism of evolution. In modified form, Darwin's scientific discovery is the unifying theory of the life sciences, explaining the diversity of life.
Darwin's early interest in nature led him to neglect his medical education at the University of Edinburgh; instead, he helped to investigate marine invertebrates. Studies at the University of Cambridge encouraged his passion for natural science. His five-year voyage onHMS Beagle established him as an eminent geologist whose observations and theories supported Charles Lyell's uniformitarian ideas, and publication of his journal of the voyagemade him famous as a popular author.
Puzzled by the geographical distribution of wildlife and fossils he collected on the voyage, Darwin began detailed investigations and in 1838 conceived his theory of natural selection. Although he discussed his ideas with several naturalists, he needed time for extensive research and his geological work had priority. He was writing up his theory in 1858 when Alfred Russel Wallace sent him an essay which described the same idea, prompting immediate joint publication of both of their theories. Darwin's work established evolutionary descent with modification as the dominant scientific explanation of diversification in nature. In 1871 he examined human evolution and sexual selection in The Descent of Man, and Selection in Relation to Sex, followed by The Expression of the Emotions in Man and Animals. His research on plants was published in a series of books, and in his final book, he examined earthworms and their effect on soil.
In recognition of Darwin's pre-eminence as a scientist, he was honoured with a major ceremonial funeral and buried in Westminster Abbey, close to John Herschel and Isaac Newton. Darwin has been described as one of the most influential figures in human history.

Descent of Man, sexual selection, and botany

Head and shoulders portrait, increasingly bald with rather uneven bushy white eyebrows and beard, his wrinkled forehead suggesting a puzzled frown
By 1878, an increasingly famous Darwin had suffered years of illness.
Letter from Charles Darwin to John Burdon-Sanderson
More detailed articles cover Darwin's life from Orchids to Variation, from Descent of Man to Emotions and fromInsectivorous Plants to Worms
Despite repeated bouts of illness during the last twenty-two years of his life, Darwin's work continued. Having publishedOn the Origin of Species as an abstract of his theory, he pressed on with experiments, research, and writing of his "big book". He covered human descent from earlier animals including evolution of society and of mental abilities, as well as explaining decorative beauty in wildlife and diversifying into innovative plant studies.
Enquiries about insect pollination led in 1861 to novel studies of wild orchids, showing adaptation of their flowers to attract specific moths to each species and ensure cross fertilisation. In 1862 Fertilisation of Orchids gave his first detailed demonstration of the power of natural selection to explain complex ecological relationships, making testable predictions. As his health declined, he lay on his sickbed in a room filled with inventive experiments to trace the movements of climbing plants. Admiring visitors included Ernst Haeckel, a zealous proponent of Darwinismus incorporatingLamarckism and Goethe's idealism. Wallace remained supportive, though he increasingly turned to Spiritualism.
The Variation of Animals and Plants under Domestication of 1868 was the first part of Darwin's planned "big book", and included his unsuccessful hypothesis of pangenesis attempting to explain heredity. It sold briskly at first, despite its size, and was translated into many languages. He wrote most of a second part, on natural selection, but it remained unpublished in his lifetime.
Darwin's figure is shown seated, dressed in a toga, in a circular frame labelled "TIME'S METER" around which a succession of figures spiral, starting with an earthworm emerging from the broken letters "CHAOS" then worms with head and limbs, followed by monkeys, apes, primitive men, a loin cloth clad hunter with a club, and a gentleman who tips his top hat to Darwin.
Punch's almanac for 1882, published shortly before Darwin's death, depicts him amidst evolution from chaos to Victorian gentleman with the title Man Is But A Worm.
Lyell had already popularised human prehistory, and Huxley had shown that anatomically humans are apes. With The Descent of Man, and Selection in Relation to Sex published in 1871, Darwin set out evidence from numerous sources that humans are animals, showing continuity of physical and mental attributes, and presented sexual selection to explain impractical animal features such as the peacock's plumage as well as human evolution of culture, differences between sexes, and physical and cultural racial characteristics, while emphasising that humans are all one species. His research using images was expanded in his 1872 book The Expression of the Emotions in Man and Animals, one of the first books to feature printed photographs, which discussed the evolution of human psychology and its continuity with the behaviour of animals. Both books proved very popular, and Darwin was impressed by the general assent with which his views had been received, remarking that "everybody is talking about it without being shocked." His conclusion was "that man with all his noble qualities, with sympathy which feels for the most debased, with benevolence which extends not only to other men but to the humblest living creature, with his god-like intellect which has penetrated into the movements and constitution of the solar system–with all these exalted powers–Man still bears in his bodily frame the indelible stamp of his lowly origin."
His evolution-related experiments and investigations led to books on Insectivorous Plants, The Effects of Cross and Self Fertilisation in the Vegetable Kingdom, different forms of flowers on plants of the same species, and The Power of Movement in Plants. In his last book he returned to The Formation of Vegetable Mould through the Action of Worms.

Death and legacy

He died at Down House on 19 April 1882. His last words were to his family, telling Emma "I am not the least afraid of death – Remember what a good wife you have been to me – Tell all my children to remember how good they have been to me", then while she rested, he repeatedly told Henrietta and Francis "It's almost worth while to be sick to be nursed by you". He had expected to be buried in St Mary's churchyard at Downe, but at the request of Darwin's colleagues, after public and parliamentary petitioning, William Spottiswoode(President of the Royal Society) arranged for Darwin to be buried in Westminster Abbey, close to John Herschel and Isaac Newton.
Man dressed as Charles Darwin during Lyme RegisFossil Festival.
Darwin had convinced most scientists that evolution as descent with modification was correct, and he was regarded as a great scientist who had revolutionised ideas. Though few agreed with his view that "natural selection has been the main but not the exclusive means of modification", he was honoured in June 1909 by more than 400 officials and scientists from across the world who met in Cambridge to commemorate his centenary and the fiftieth anniversary of On the Origin of Species. During this period, which has been called "the eclipse of Darwinism", scientists proposed various alternative evolutionary mechanisms which eventually proved untenable. The development of the modern evolutionary synthesis from the 1930s to the 1950s, incorporating natural selection with population genetics and Mendelian genetics, brought broad scientific consensus that natural selection was the basic mechanism of evolution. This synthesis set the frame of reference for modern debates and refinements of the theory.
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