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Charles Darwin

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Charles Robert Darwin (February 12, 1809 - April 19, 1882) was a British naturalist who achieved fame as originator of the theory of evolution through natural selection.

Considered the "father of evolutionary theory," Darwin made two contributions of enormous impact to the idea of evolution. First, Darwin marshaled substantial evidence for the theory of descent with modification, a kinematic theory that treats non-causal relations between things-it deals with the pattern of evolution. Secondly, Darwin proposed a mechanism for that observed pattern, the theory of natural selection. This is a dynamic theory that involves mechanisms and causal relationships-it deals with the process of evolution.

Darwin's interest in natural history developed at the college level, while studying first medicine, then theology. But it was his five-year voyage on the HMS Beagle that began his road to eminence. His biological observations at that time led him to study transmutation of species and develop his theory of natural selection in 1838 and the draft of a preliminary manuscript in 1842. He confided only in close friends, but in 1858 the information that Alfred Russel Wallace now had a similar theory forced early joint presentation of the theory.

Darwin's 1859 book, The Origin of Species by Means of Natural Selection, or The Preservation of Favoured Races in the Struggle for Life (usually abbreviated to The Origin of Species), established evolution by common descent as the dominant scientific theory of diversification in nature, and it established natural selection as a contender for explaining the diversity of life. He was made a Fellow of the Royal Society, continued his research, and wrote a series of books on plants and animals, including humans in The Descent of Man and Selection in Relation to Sex and The Expression of the Emotions in Man and Animals. His last book was about earthworms.

In recognition of Darwin's pre-eminence, he is buried in Westminster Abbey, close to Sir William Herschel and Sir Isaac Newton.

Darwin's theory of descent with modification, which is neutral with respect to the process involved, was accepted soon after its introduction, and substantial evidence has been accumulated in its support. In contrast, Darwin's theory of modification through natural selection was, at its core, revolutionary and controversial, positing a process that went against prevailing concepts at the time. (See radical components.) It was not well accepted by the scientific community until the middle of the twentieth century. Furthermore, the theory that natural selection serves as the main directive force of large-scale evolutionary changes and new designs (macroevolution) remains controversial in various quarters today, and its evidences remain largely confined to extrapolations from evolution observed within species or populations (microevolution).

Darwin has been claimed as a "patron saint" of materialists who identify the mechanism of natural selection operating on variability as a great nail in the coffin of God and all related matters of spirit and religion. The proven efficacy of natural selection, they claim, is ample justification for disposing of any idea that a deity may have had even a small role in creating either new species, marvelous mechanisms such as the human eye, or human beings. Yet, at the same time, such views are a great affront to many religious people who have viewed the marvels of the natural world as the handiwork of a Creator God. Many religious people hold the view that the directing or creative force in the observed pattern of evolution is a Creator or God and that although natural selection may be a force for change within a species or population, it cannot be the ultimate source of major new designs or the remarkable diversity of species. However, there actually is a great diversity of religious belief regarding Darwin's theories, from those that stand in opposition to both the theory of descent with modification and the theory of natural selection (such as "young-earth" creationists), to those that accept the pattern observed in nature (theory of descent with modification) but not the process (theory of natural selection), and still others who accept natural selection as the causal agent of large-scale change.

Darwin's ideas and impact

Synopsis of Darwin's ideas

Charles Darwin in 1854, five years before he published The Origin of Species.

There are two major components in Darwin's theory of evolution: (1) the theory of descent with modification; and (2) the theory of modification through natural selection.

The "theory of descent with modification" (or "theory of evolution by common descent") essentially postulates that all organisms have descended from common ancestors by a continuous process of branching. In other words, all life evolved from one kind of organism or from a few simple kinds, and each species arose in a single geographic location, from another species that preceded it in time. Evolutionists have marshaled substantial evidence for the theory of descent with modification. That is, the "pattern of evolution" is documented by the fossil record, the distribution patterns of existing species, methods of dating fossils, and comparison of homologous structures, among others.

The second theory of Darwin, the "theory of modification through natural selection" (or, simply, "theory of natural selection"), holds that natural selection is the directing or creative force of evolution. It recognizes that individuals in a population are not all the same (there are variations), some of these variations are heritable, all organisms produce more offspring than can survive, and those surviving to reproduce have the best fit to the environment, such that favorable traits will accumulate and unfavorable traits will decline and be lost-perhaps to the extent that a new species will be formed. Note that natural selection is considered far more than just a minor force for weeding out unfit organisms. Even Paley and other natural theologians accepted natural selection, albeit as a devise for removing unfit organisms, rather than as a directive force for creating new species and new designs.

Concrete evidence for the theory of modification by natural selection is limited to microevolution, such as seen in the case of artificial selection (whereby various breeds of animals and varieties of plants have been produced that are different in some respect from their ancestors), or in natural selection within populations or species (such as the often-cited, but somewhat problematic case of systematic color change in the peppered moth, Biston betularia). The evidence that natural selection directs the major transitions between species and originates new designs (macroevolution) necessarily involves extrapolation from these evidences on the microevolutionary level. One of Darwin's chief purposes in publishing the Origin of Species was to show that natural selection had been the chief agent of the change presented in the theory of descent with modification. The validity of making this extrapolation has recently come under strong challenge from top evolutionists.

In Darwin's comprehensive theory of evolution, there can actually be elucidated at least three additional, major, largely independent theories: (1) evolution as fact; (2) populational speciation; and (3) gradualism. Darwin strived to establish the "fact of evolution," countering the view of most people and scientists at the time that the world was constant. Darwin also looked at speciation as a populational phenomenon; the population gradually changed until it became a new species. Thirdly, Darwin also insisted that evolution was entirely gradual, that evolution proceeded by means of the slow, steady accumulation of slight favorable variations. Indeed, he stated in the Origin of Species:

  • "As natural selection acts solely by accumulating slight, successive, favourable variations, it can produce no great or sudden modifications; it can act only by very short and slow steps."
  • "If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down."

This insistence that evolution is entirely gradual encountered much resistance, since there seemed to be strong differences between different types, and paleontologists failed to find intermediate types in the fossil record. Today, this concept remains in doubt, with the presentation of various punctuational models for speciation and for the origin of new designs.

Radical components

Although concepts of evolution were not uncommon in the first half of the nineteenth century, Darwin's theory of modification through natural selection operating on expressed variability was radical in three of its foundational premises:

  1. Purposeless. A higher purpose is not required or utilized to explain the seeming harmony in the world. The orthodox view at the time was that one observed harmony in nature because everything had a preordained role. Darwin's theory cut through this orthodoxy with the view that there is no higher purpose; rather, any apparent harmony is actually the fruit of an underlying struggle of individuals to survive and reproduce.
  2. Philosophical materialism. Matter is to be recognized as the main reality of existence, and mental and spiritual phenomena, including thought, will, and feeling, are to be explained in terms of matter, as its by-products. By advocating a materialist account of life, Darwin launched biology on a trajectory that would contravene one of the strongest traditions of Western thought: the dualist separation of mind and matter, with an elevated status for mind1. Rather, in Darwin's view, the human mind is a natural outcome of selective pressures for a large and complex brain.
  3. No inherent progress. Darwin stated that evolution is not inherently progressive; it does not lead inexorably to an improvement of life over time. That is, life does not move from lower to higher states, and indeed, there is no "higher" or "lower" with reference to the structure of organisms. Natural selection only adapts organisms to their local environments. Although natural selection has led to evolving a human, it has also produced the extreme morphological degeneration of many parasites. Darwin granted humans no special status2

In actuality, it is the theory of modification through natural selection, rather than the theory of descent with modification, that had these three radical components. By providing a purely non-theological, materialistic explanation for all phenomena of living nature, it was said it "dethroned God." So radical were Darwin's ideas that it has been speculated that, after developing the idea of natural selection, Darwin waited more than 20 years to publish his theory because of its societal implications.

Most religious perspectives do not adhere to the three radical premises that undergird and also emanate from the theory of natural selection: purposelessness, philosophical materialism, and the view that life has not developed progressively. Rather, they attribute a Creator or God as the ultimate force impacting variability and yielding the observed pattern of evolution. Natural selection is recognized as a force for microevolutionary change (within species), or acting on designed variability, but not as directive force responsible for the creation of major new designs or phyla from randomly generated variability.

Importance of Darwin's thought

Charles Darwin was revered by many as a great thinker

Prior to the publication of Darwin's The Origin of Species in 1859, the field of evolutionary biology was nearly non-existent. Soon it would become the focus of intense activity, and today a vast literature, including entire periodicals, are devoted to this field and its various specialties. The extensive effort devoted to the study of Darwin himself, and his writings, has led to a common designation: "Darwin industry."

Darwin's theory of evolution based upon natural selection changed the thinking of countless fields of study from biology to anthropology. His work established that "evolution" had occurred: not necessarily that it was by natural or sexual selection. (Although by the time of Darwin's death in 1882, the fact of evolution was almost universally accepted by his contemporaries, the mechanism for this evolution-the theory of natural selection-did not become an orthodoxy until long after his death, and particularly only after the rediscovery of Gregor Mendel's work in the early twentieth century and the inception of the modern synthesis.)

The impact of Darwin's ideas on current teachings of evolutionary theory is readily visible. Darwin's books, The Origin of Species (1859) and The Descent of Man (1871), contain discussions that are still largely applicable and utilized today. These cover such themes as the basics of natural selection, sexual selection, diverse definitions for species, analogous resemblances and convergence, homologous structures, embryological development, and vestigial organs as evidence for descent of humans, fossils as evidence of evolution, classification on evolutionary principles, and so forth. Note, for example, a concept taken directly from The Origin of Species, which is just one of many that are frequently found closely mirrored in the text and illustrations of secondary school biology textbooks: "What can be more curious than that the hand of man, formed for grasping, that of a mole for digging, the leg of a horse, the paddle of the porpoise, and the wing of the bat, should all be constructed on the same pattern, and should include the same bones, in the same relative positions?" Ernst Mayr relates that the most convincing proofs of evolution in modern times are the very areas that Darwin has presented as evidences: biogeography, paleontology, morphology, classification, and embryology.

Of course, innumerable developments in evolutionary theory have taken place since the time of Darwin, and some of Darwin's concepts have proven wrong. Darwin accepted both the principle of use and disuse (Lamarck's "First Law") and the formulation of inheritance of acquired characteristics (Lamarck's "Second Law"). In The Origin of Species, he stated that "there can be little doubt that use in our domestic animals strengthens and enlarges certain parts and disuse diminishes them; and that such modifications are inherited." Indeed, Darwin devoted an entire section in chapter 5 to the concept of use and disuse. However, since Darwin's time the concepts of use and disuse and the inheritance of acquired characteristics have been generally discredited. Also, since Darwin's time, there has been a melding of evolutionary theory with ecology, behavioral biology, and molecular biology, and the laws governing inheritance have been greatly illuminated.

Commemoration

During Darwin's lifetime many species and geographical features were given his name, including the Darwin Sound, named by HMS Beagles Robert FitzRoy after Darwin's prompt action saved them from being marooned, and the nearby Mount Darwin in the Andes, which FitzRoy named in celebration of Darwin's twenty-fifth birthday. In Australia's Northern Territory, the capital city (originally Palmerston) was renamed Darwin to commemorate the Beagle's 1839 visit there, and the territory now also boasts Charles Darwin University and Charles Darwin National Park.

The 14 species of finches he researched in the Galápagos Islands are affectionately named "Darwin's Finches" in honor of his legacy. In 1964, Darwin College, Cambridge was founded, named in honor of the Darwin family, partially because they owned some of the land it was on. In 1992, Darwin was ranked sixteenth on Michael H. Hart's list of the most influential figures in history. Darwin was given particular recognition in 2000 when his image appeared on the Bank of England ten-pound note, replacing Charles Dickens. Darwin was fourth in the 100 Greatest Britons poll sponsored by the BBC and voted for by the public.

Biography

Early life

The seven-year-old Charles Darwin in 1816, a year before the sudden, tragic loss of his mother.

Charles Darwin was born in Shrewsbury, Shropshire, England, on February 12, 1809, at the family home, The Mount House. He was the fifth of six children of Robert Darwin and Susannah Darwin (née Wedgwood), and the grandson of Erasmus Darwin, and of Josiah Wedgwood, both from the prominent Darwin-Wedgwood family, which supported the Unitarian Church. His mother died when he was only eight. The next year he went to the nearby Shrewsbury School where he lived there as a "boarder."

In 1825, Darwin went to Edinburgh University to study medicine, but his revulsion at the brutality of surgery led him to neglect his medical studies. He studied taxidermy with a freed black slave from South America, and found his tales of the South American rainforest absorbing. In Darwin's second year, he became active in student societies for naturalists. He became an avid student of Robert Edmund Grant, who enthusiastically followed the theories of Jean-Baptiste Lamarck and Charles's grandfather Erasmus about evolution by acquired characteristics. Grant's pioneering investigations of the life cycle of marine animals on the shores of the Firth of Forth found evidence for homology, then the name for the radical theory that all animals have similar organs and differ only in complexity. Darwin took part in these investigations and in March 1827 made a presentation to the Plinian Society of his discovery that black spores often found in oyster shells were the eggs of a skate leech. He also sat in on Robert Jameson's natural history course, learning about stratigraphic geology and assisting with work on the collections of the Museum of Edinburgh University, then one of the largest in Europe.

In 1827, his father, unhappy that his younger son would not become a physician, enrolled him in a Bachelor of Arts course at Christ's College, University of Cambridge, which would qualify him to be a clergyman. This was a sensible career move at a time when Anglican's were provided with a comfortable income, and when most naturalists in England were clergymen who saw it as part of their duties to explore the wonders of God's creation. At Cambridge, Darwin preferred riding and shooting to studying. Along with his cousin William Darwin Fox, he became engrossed in the current craze for the competitive collecting of beetles, and Fox introduced him to the Reverend John Stevens Henslow, professor of botany, for expert advice on beetles. Darwin subsequently joined Henslow's natural history course, becoming the "favorite pupil," known as "the man who walks with Henslow." When exams loomed, he focused on his studies and received private tutoring from Henslow, whose subjects were math and theology. Darwin became particularly enthused by texts by William Paley which included the argument of divine design in nature. In his finals in January 1831, Darwin performed well in theology and, having done well enough in the classics, mathematics, and physics, was tenth out of a pass list of 178.

Residential requirements now kept Darwin at Cambridge until June. In line with Henslow's example and advice, he was in no rush to take holy orders. Inspired by Alexander von Humboldt's Personal Narrative, he planned to visit Madeira to study natural history in the tropics with some classmates after graduation. To prepare for this project, Darwin now joined the geology course of the Reverend Adam Sedgwick, then during the summer break worked with him at mapping strata in Wales. Darwin was surveying strata in Wales on his own when his plans to visit Madeira were dashed by a message that his intended companion had died, but on his return home he received another letter. Henslow had recommended Darwin for the unpaid position of gentleman's companion to Robert FitzRoy, the captain of HMS Beagle, on a two-year expedition to chart the coastline of South America which would give Darwin valuable opportunities to develop his career as a naturalist. His father objected to the voyage, regarding it as a waste of time, but was persuaded by Josiah Wedgwood to agree to his son's participation. This voyage became a five-year expedition that would change science dramatically.

Journey on the Beagle

HMS Beagle surveyed wild coasts of South America.

The HMS Beagle survey took five years, two-thirds of which Darwin spent exploring on land. He studied firsthand a rich variety of geological features, fossils, and living organisms, and met a wide range of people, both native and colonial. He methodically collected an enormous number of specimens, many of them new to science, which established his reputation as a naturalist and made him one of the precursors of the field of ecology. His detailed notes formed the basis for his later work and provided social, political, and anthropological insights into the areas he visited. Darwin read Charles Lyell's Principles of Geology, which explained features as the outcome of gradual processes over huge periods of time, and wrote home that he was seeing landforms "as though he had the eyes of Lyell": stepped plains of shingle and seashells in Patagonia appeared to be raised beaches; in Chile, he experienced an earthquake that raised the land; and high in the Andes, he collected seashells. He theorized that coral atolls form on sinking volcanic mountains, and when the Beagle reached the Cocos (Keeling) Islands its survey supported his theory.

In South America, Darwin discovered fossils of gigantic extinct Megatheriums and Glyptodons in strata which showed no signs of catastrophe or change in climate. At the time, he thought them similar to African species, but after the voyage, Richard Owen showed that the remains were of animals related to living creatures in the same area. Darwin found different mockingbirds on nearby Galápagos Islands, and on returning to Britain he was shown that Galápagos tortoises and finches were also distinct species related to the islands. An Australian marsupial rat-kangaroo and a platypus were such strikingly different creatures as to cause him to remark that "An unbeliever… might exclaim 'Surely two distinct Creators must have been at work.'" In the first edition of The Voyage of the Beagle, he explained species distribution in the light of Charles Lyell's ideas of “centres of creation”; however, in later editions of this Journal he foreshadowed his use of Galápagos Islands fauna as evidence for evolution: "one might really fancy that from an original paucity of birds in this archipelago, one species had been taken and modified for different ends."

While on board the ship, Darwin suffered from seasickness. In October 1833 he caught a fever in Argentina, and in July 1834 (returning from the Andes down to Valparaiso) he fell ill and spent a month in bed.

Career in science, inception of theory

While still a young man, Charles Darwin became eminent as a naturalist.

While Darwin was still on the voyage, Henslow carefully fostered his former pupil's reputation by giving selected naturalists access to the fossil specimens and printed copies of Darwin's geological writings. When the Beagle returned on October 2, 1836, Darwin was a celebrity in scientific circles. He visited his home in Shrewsbury and his father organized investments so that Darwin could become a self-funded gentleman scientist. After visiting Cambridge and getting Henslow to agree to work on botanical descriptions of modern plants he had collected, Darwin went to London institutions to find the best naturalists available to describe his other collections for timely publication. An eager Charles Lyell met Darwin on October 29 and introduced him to the up-and-coming anatomist Richard Owen. After working on Darwin's collection of fossil bones at his Royal College of Surgeons, Owen caused great surprise by revealing that some were from gigantic extinct rodents and sloths. This enhanced Darwin's reputation.

With Lyell's enthusiastic backing, Darwin read his first paper to the Geological Society of London on January 4, 1837, arguing that the South American landmass was slowly rising. On the same day, Darwin presented his mammal and bird specimens to the Zoological Society. Though the birds seemed almost an afterthought, the ornithologist John Gould revealed that what Darwin had taken to be wrens, blackbirds, and slightly differing finches from the Galápagos were all finches, but each was a separate species. Others on the Beagle, including FitzRoy, had also collected these birds and had been more careful with their notes, enabling Darwin to find which island each species had come from.

In London, Charles stayed with his brother Erasmus. Scientific circles were buzzing with ideas of transmutation of species. Darwin preferred the company of his friends, the Cambridge Dons, even though his ideas were pushing beyond their belief that natural history must justify religion and social order.

On February 17, 1837, Lyell used his presidential address at the Geographical Society to present Owen's findings to date on Darwin's fossils, pointing out the inference that extinct species were related to current species in the same locality. At the same meeting, Darwin was elected to the Council of the Society. He had already been invited by FitzRoy to contribute a Journal, based on his field notes, as the natural history section of the captain's account of the Beagle's voyage. He now plunged into writing a book on South American geology. At the same time, he speculated on transmutation in his Red Notebook, which he had begun on the Beagle. Another project he started was getting the expert reports on his collection published as a multivolume Zoology of the Voyage of HMS Beagle, and Henslow used his contacts to arrange a treasury grant of £1,000 to sponsor this. Darwin finished writing his Journal around June 20 (when King William IV died and the Victorian Era began). In mid-July, Darwin began his secret "B" notebook on transmutation, and developed the hypothesis that where every island in the Galápagos Archipelago had its own kind of tortoise, these had originated from a single tortoise species and had adapted to life on the different islands in different ways.

While organizing Zoology and correcting proofs of his Journal, Darwin's health suffered. On September 20, 1837, he suffered "palpitations of the heart" and left for a month of recuperation in the countryside. He visited Maer Hall where his invalid aunt was being cared for by her daughter Emma Wedgwood, and entertained his relatives with tales of his travels. Darwin avoided taking on official posts that would take valuable time, but by March he was recruited to serve as Secretary of the Geological Society.

Charles chose to marry his first cousin Emma Wedgwood.

Upon being fully recuperated, Darwin returned home to Shrewsbury. Pondering his career and prospects he drew up a list with columns headed "Marry" and "Not Marry." Having come down in favor of marrying, he discussed it with his father, and then went to visit his cousin Emma on July 29, 1838. He did not get around to proposing, but against his father's advice he told her of his ideas on transmutation.

While his thoughts and work continued in London over the autumn, Darwin suffered repeated bouts of illness. On November 11, he returned and proposed to Emma, once more telling her his ideas. She accepted, but later wrote beseeching him to read from the Gospel of Saint John a section on love and following the Way which also states that "If a man abide not in me… they are burned." He sent a warm reply which eased her concern, but she would continue to worry that his lapses of faith could endanger her hope that they would meet in an afterlife.

Darwin considered Malthus's argument that human populations breed beyond their means and compete to survive. He related this to findings about species relating to localities, his inquiries into animal breeding, and ideas of natural "laws of harmony." Towards the end of November 1838, Darwin compared breeders' selecting traits to a Malthusian Nature selecting from variants thrown up by "chance" so that "every part of newly acquired structure is fully practised and perfected." Darwin thought this "the most beautiful part of my theory" of how species originated.

Darwin went house-hunting and eventually found "Macaw Cottage" in Gower Street, London, and then moved his "museum" there over Christmas. He was showing signs of stress, and Emma wrote urging him to get some rest, almost prophetically remarking "So don't be ill any more my dear Charley till I can be with you to nurse you." On January 24, 1839, Darwin was honored by being elected as Fellow of the Royal Society and presented a paper on the Roads of Glen Roy.

Marriage and children

On January 29, 1839, Darwin married his cousin Emma Wedgwood (May 2, 1808 - October 7, 1896) at Maer in an Anglican ceremony arranged to also suit the Unitarians.

After first living in Gower Street, London, the couple moved on September 17, 1842, to Down House in Downe. The Darwins had ten children, three of whom died early. Many of these and their grandchildren would later achieve notability themselves.

The devoted father Charles Darwin photographed with his son William in 1842.
  • William Erasmus Darwin (December 27, 1839 - 1914)
  • Anne Elizabeth Darwin (March 2, 1841 - April 22, 1851)
  • Mary Eleanor Darwin (September 23, 1842 - October 16, 1842)
  • Henrietta Emma "Etty" Darwin (September 25, 1843 - 1929)
  • George Howard Darwin (July 9, 1845 - December 7, 1912)
  • Elizabeth "Bessy" Darwin (July 8, 1847 - 1926)
  • Francis Darwin (August 16, 1848 - September 19, 1925)
  • Leonard Darwin (January 15, 1850 - March 26, 1943)
  • Horace Darwin (May 13, 1851 - September 29, 1928)
  • Charles Waring Darwin (December 6, 1856 - June 28, 1858).

Several of their children suffered illness or weaknesses, and Charles Darwin's fear that this might be due to the closeness of his and Emma's lineage was expressed in his writings on the ill effects of inbreeding and advantages of crossing.

Career and development of theory

Darwin was now an eminent geologist in the scientific elite 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 his theory 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

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