Charles Darwin

   

Charles Robert Darwin (February 12, 1809 - April 19, 1882) was an English naturalist whose revolutionary theory laid the foundation for both the modern theory of evolution and the principle of common descent by proposing natural selection as a mechanism. He published this proposal in 1859 in the book The Origin of Species, which remains his most famous work. A worldwide sea voyage aboard HMS Beagle and observations on the Galapagos Islands in particular provided inspiration and much of the data on which he based his theory.

Charles Robert Darwin in 1854, five years prior to the publishing of The Origin of Species
Charles Robert Darwin in 1854, five years prior to the publishing of The Origin of Species

Early life

A seven-year old Charles Darwin in 1816
Enlarge
A seven-year old Charles Darwin in 1816

Charles Darwin was born in Shrewsbury, Shropshire, England, on February 12, 1809 (coincidentally, the same day as Abraham Lincoln). He was the fifth of six children of Robert and Susannah Darwin (née Wedgwood), and the grandson of Erasmus Darwin, and of Josiah Wedgwood. See also Darwin -- Wedgwood family.

After finishing school, Darwin studied medicine in Edinburgh in 1825. His dislike for dissection and the brutality of surgery at the time led him to leave the medical school in 1827. Whilst there, however, he was influenced by the Lamarckian Robert Edmund Grant.

His father, unhappy that his younger son had not become a physician and fearing that he would become a "ne'er do well", enrolled him at Christ's College, Cambridge, with the hopes of Charles' eventually becoming a parson. He preferred riding and shooting to studying, but while at Cambridge, he came under the intellectual influence of scientific minds such as William Whewell and John Stevens Henslow which (combined with his interest in collecting beetles, which was encouraged by his cousin, William Darwin Fox) resulted in him pursuing natural history.

After taking his degree with honours, Darwin stayed at Cambridge for further studies in geology, where he proved particularly adept. In the summer of 1831, Darwin worked with the great geologist Adam Sedgwick mapping strata in Wales.

Darwin had planned to visit Madeira with some class-mates upon graduation in 1831. These plans, however, fell through. After Darwin finished his studies, Henslow recommended him for the position of naturalist and gentleman's companion to Robert Fitzroy, the captain of HMS Beagle, which was departing on a five-year expedition to chart the coastline of South America. His father objected to the expedition, thinking it a waste of his son's time, but was eventually persuaded to let him go.

Journey on the Beagle

HMS Beagle, from an 1841 watercolour by Owen Stanley
Enlarge
HMS Beagle, from an 1841 watercolour by Owen Stanley

Darwin's work during the Beagle expedition allowed him to study both the geological properties of continents and isles and a multitude of living organisms and fossils. He collected an enormous number of specimens new to science in a very methodical way, and his specimens sent back to the British Museum were by themselves a significant contribution to science, and made him one of the precursors of ecology. No other collector has rivalled his work since. He also took many detailed notes on everything he observed, which would form the basis for his later work.

During his voyage, he visited the Cape Verde Archipelago, the Falkland Islands, the South American coast, the Galapagos Islands, New Zealand and Australia, meeting native peoples, seeing natural wonders, and above all, collecting considerable quantities of specimens. Quite apart from the wealth of detailed biological accounts they give, Darwin's published accounts also provide us with social, political, and anthropological insights into the areas he visited. For instance his account of how the Gaucho of Argentina lived is particularly interesting. Further, the journals reveal him to be a very active and intrepid adventurer who thought nothing of embarking on 200 mile journeys across dangerous territories, in marked contrast to the better known image of an elderly country gentleman.

While in South America, he contracted Chagas' disease from insect bites. Although not fatal, it recurred several times during his life, and prevented him from being particularly active.

On his return he used his journals as the basis of a popular book, "The Voyage of the Beagle", which became a best-seller when published in 1839 and established Darwin as an author.

Darwin shapes his theory

After returning from the voyage on October 2, 1836, Darwin analyzed the specimens he collected, and noticed similarities between fossils and living species within the same geographic area. In particular, he noticed that every island in the Galapagos Archipelago had its own kind of tortoises and birds that were all slightly different in appearance, favoured food etc., but otherwise similar.

In the spring of 1837 ornithologists at the British Museum informed Darwin that the several very different species of birds he had taken in the Galapagos were all finches. This, coupled with a re-reading of Thomas Malthus' 1798 essay on populations, triggered a chain of thought that would culminate in the theory of evolution by natural and sexual selection. He developed the hypothesis that, for example, all the different turtles had originated from a single turtle species, and had adapted to life on the different islands in different ways.

Based on these thoughts, he formulated his ideas about the changes and developments of species in his Notebook on the Transmutation of Species, which was in accordance with Lyell's Principles of Geology and Thomas Malthus' Essay on the Principle of Population, which stated that the size of a population is limited by the food resources available. Realizing the potential of this understanding, Darwin undertook extensive experiments with pigeons and plants, and extensive consultation with pig breeders and other animal husbanders, in an attempt to discover holes in the hypothesis. He took his time with careful research until he had enough evidence, knowing that a great deal of opposition would likely erupt when he presented his theory.

First writings

Following his account of The Voyage of the Beagle, Darwin's Zoology of the Voyage of H.M.S. Beagle was published between 1839 and 1843 in five volumes. Darwin published scientific treatises, including an explanation for the life-cycle of coral atolls in the South Pacific published in 1842.

In 1842, Darwin formulated a short "Pencil Sketch" of his theory and by 1844 had written a 240 page "Essay" which provides an expanded version of his early ideas on natural selection. Between 1844 and 1858, when he would present his theory to the Linnean Society of London, Darwin wrote his masterpiece, modifying his theory in a number of ways as he wrote.

Marriage and children

Emma Darwin, Charles' wife
Enlarge
Emma Darwin, Charles' wife

Darwin married his cousin Emma Wedgwood in 1839. After living for a number of years in London, the couple eventually moved to Down House, in Downe, Kent (which is now open to public visits, south of Orpington). The Darwins had twelve children, three of whom died early:

The Origin of Species

Darwin's work brought him a correspondence relationship with Alfred Russel Wallace, working in the islands of the South Pacific and Indonesia. Wallace had been one of Darwin's numerous providers of natural history specimens, and was considerably lower in social status than Darwin himself. On June 18th 1858, Wallace sought Darwin's ideas on a theory Wallace had developed which almost exactly mirrored Darwin's own work. Darwin was himself horrified at the prospects of being scooped, but also felt bound to respect Wallace's claim to priority. Seeking advice from his scientific friends, he was encouraged to announce his theory along with Wallace's contribution, and to establish that he had in fact started developing the theory ten years before Wallace did. On July 1, 1858, Darwin's announcement of his theory was read to the Linnean Society, in London, jointly with Wallace's paper. Neither men were present at the reading, Darwin was at home with his dying son, and Wallace was in the Far East somewhere. The paper was entitled On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection. Fortunately for Darwin, Wallace was satisfied with the arrangement: though he would always be second-string to Darwin (his role reduced to that of catalyst), to be linked to a well-respected naturalist of high social standing like Darwin was still a fantastic career opportunity, perhaps more than he could have accomplished himself in the tight-knit circle of Victorian-era science.

The initial announcement of the theory garnished little immediate attention. It was mentioned briefly in a few small reviews but did not yet command much further thought, and was not yet fully distinguishable to most people from other varieties of evolutionary thought. For the next thirteen months, Darwin would labor to produce what was originally to be an abstract of his "big book on species." Receiving constant promotion and encouragement from his scientific friends, Darwin finally finished On the Origin of Species by Means of Natural Selection and arranged to have it published. Through his network of social connections and correspondents, Darwin's book was given a great deal of initial attention, marketed by his scientifically respectable friends as being a worthy contribution to scientific thought, and with reviews placed in prominent periodicals. As attention and controversy gathered, the book was translated into numerous languages and went through a number of reprints, becoming a staple scientific text accessible to a newly curious middle class. It would prove to be the most controversial and discussed scientific book ever written.

It provoked an outraged response from the Church of England. At a meeting of the British Association for the Advancement of Science in Oxford, 'Soapy Sam' Wilberforce, the Bishop of Oxford, and Robert Fitzroy (the Captain of HMS Beagle) argued against Darwin, and Thomas Huxley established himself as "Darwin's bulldog" – the fiercest defender of evolutionary theory on the Victorian stage. On being asked by Wilberforce, whether he was descended from monkeys on his grandfather's side or his grandmother's side, Huxley, recognizing his opportunity, apparently muttered to himself: "The Lord has delivered him into my hands", and then replied that he "would rather be descended from an ape than from a cultivated man who used his gifts of culture and eloquence in the service of prejudice and falsehood" (several alternative versions of this supposed quote exist, see Wilberforce and Huxley: A Legendary Encounter (http://users.ox.ac.uk/~jrlucas/legend.html)). The story spread around the country: Huxley had said he would rather be an ape than a Bishop.

Darwin himself did not personally defend his theories in public, though he watched the ongoing debates eagerly. He was constantly in ill health, and preferred to garnish support by means of his letters and correspondence. A core circle of scientific friends–Huxley, Charles Lyell, Joseph Dalton Hooker, and Asa Gray–actively pushed his work onto the fore of the scientific and public stage, and defended him against his many mounting critics. Unexpectedly to Darwin, his theory became not only a key scientific controversy of the era, but was also resonated with many anti-Victorian sentiments at the time, becoming a key fixture of popular culture of the period (and beyond).

Later works and death

In several of his later books The Variation of Animals and Plants Under Domestication (1868), The Descent of Man and Selection in Relation to Sex (1871) and The Expression of Emotions in Animals and Man (1872), Darwin expanded on many topics introduced in Origin of Species. The Descent of Man, in particular, aroused even greater argument since it theorized that humanity was descended from apes. Forever afterward, Darwin would be characterized as "the monkey man," and cartoons often depicted him as part ape (see below).

Darwin's life work provoked ongoing discussions in the scientific community, and established more than anything else that "evolution" itself had occurred: not necessarily that it was by natural or sexual selection (this particular recognition would not become fully standard until the rediscovery of Gregor Mendel's work in the early 20th century). He became a member of the Royal Society of London in 1839 (on the basis of his collecting during his voyages) and of the French Academy of Sciences (l'Académie des Sciences) in 1878.

The classic image of Darwin as an old man
Enlarge
The classic image of Darwin as an old man

Darwin died in Downe, Kent, England, on 19 April 1882 and was given a state funeral. William Spottiswoode, President of the Royal Society arranged for Darwin to be buried in Westminster Abbey near Isaac Newton, despite Darwin's wishes that he be buried in Downe.

Darwin was given particular recognition in 2000 when his image appeared on the Bank of England ten pound note, replacing Charles Dickens. His impressive and supposedly hard-to-forge beard was reportedly a contributing factor in this choice.

Before Darwin

Prior to the nineteenth century, the accepted theory for the extinction of species was called Catastrophism. This propounded the belief that animals and plants were periodically wiped out as a result of natural catastrophes and that their places were taken by the creation of new species ex nihilo (out of nothing). The extinct organisms could then be observed in the fossil record and their replacements were considered to be immutable. This explanation fitted in neatly with the story of the Flood in the Bible.

In the early nineteenth century, several alternative and radical ideas started to emerge. Charles's grandfather Erasmus hypothesized that all warm-blooded animals sprang from a single living "filament" long, long ago. Probably the most important one was developed by Jean-Baptiste Lamarck (1744-1829) who observed that every new generation inherits some characteristics of its ancestors. His suggested mechanism for this process was that an individual's traits or organs became enhanced with repeated use, and weakened or removed by disuse. These changes would then be passed directly on to its offspring!

Between 1830-1833, the eminent British geologist Sir Charles Lyell released a three volume publication called Principles of Geology which effectively rejected the Catastrophism Theory. This gave additional support to the concept of uniformitarianism, which stated that the Earth's surface gradually altered over eons of time by the constant action of natural geological processes.

Darwin's theory of evolution

Darwin's theory of evolution is based on five key observations and inferences drawn from them. These observations and inferences have been summarized by the great biologist Ernst Mayr as follows:

  • First, species have great fertility. They make more offspring than can grow to adulthood.
  • Second, populations remain roughly the same size, with modest fluctuations.
  • Third, food resources are limited, but are relatively constant most of the time. From these three observations it may be inferred that in such an environment there will be a struggle for survival among individuals.
  • Fourth, in sexually reproducing species, generally no two individuals are identical. Variation is rampant.
  • And fifth, much of this variation is heritable.

From this it may be inferred: In a world of stable populations where each individual must struggle to survive, those with the "best" characteristics will be more likely to survive, and those desirable traits will be passed to their offspring. These advantageous characteristics are inherited by following generations, becoming dominant among the population through time.

This is natural selection.

It may be further inferred that natural selection, if carried far enough, makes changes in a population, eventually leading to new species. These observations have been amply demonstrated in biology, and even fossils demonstrate the veracity of these observations.

Darwin imagined it might be possible that all life is descended from an original species from ancient times. DNA evidence supports this idea.

Response to Darwin's theory

Caricature of Darwin as an ape in the Hornet magazine
Enlarge
Caricature of Darwin as an ape in the Hornet magazine

After the publication of Darwin's book, evolution as the means of natural selection was widely discussed, particularly by the religious and the scientific communities. Though Darwin was supported by some scientists (e.g., T.H. Huxley), others hesitated to accept the theory due to the unexplained ability of individuals to pass their special abilities to their offspring. The last point remained a mystery until the existence of genes was discovered (Gregor Mendel had worked out his laws of heredity by 1865, but they remained unknown to the scientific community, including Darwin, until the 20th century).

In 1902 Peter Kropotkin published the book Mutual Aid: A Factor of Evolution, challenging Darwin's Theory as too narrow. In 1874, the theologian Charles Hodge accused Darwin of denying the existence of God by defining humans to be a result of a natural process rather than a creation designed by God (an argument though that had been made by many almost immediately after Darwin's first publication). Darwin's theory is now backed up by the comparison of DNA from different organisms which shows the closeness of their relationship.

Today, whilst the overwhelming majority of biologists consider Darwin's basic theory correct, a significant fraction of the general population, particularly in the United States, disagree mainly on religious grounds (see creationism).

Evolution is in complete contradiction with many of the legendary or religious stories of how the world's life originated; therefore, those that accepted the theory grew more sceptical of the Bible and other religious sources. As Hodge pointed out, evolution does not seem to originate from a divine source, and some viewed God as a less powerful force in the universe.

Darwin's theory changed the way humans saw themselves and their world. If one accepted that humans were descended from animals, it becomes clearer that humans are animals themselves. The natural world took on a darker tinge in the minds of many, as animals were understood to be in a constant state of competition with one another. The world was also seen in a less permanent fashion; since the world was apparently much different millions of years ago, it dawned on many that the impact of human beings would lessen and perhaps disappear altogether over time.

Contrary to popular opinion, Darwin did not "discover" evolution as it was accepted by many since the beginning of the 1800s. Instead, he and Wallace discovered the first really coherent mechanism that explains how evolution occurs: natural selection. Darwin's work, however, established for most that evolution of some form did occur–that there was no fixity of species–even if there was considerable disagreement on the mechanism. Also contrary to a common misstatement, Darwin did not invent Survival of the fittest, but added this in the 6th edition of The Origin of Species, giving due credit to Herbert Spencer and usually using the phrase "Natural Selection, or the Survival of the Fittest".

Other important aspects of Darwin's overall theory which themselves evolved over time were: common descent, sexual selection, gradualism, and pangenesis.

It is important to remember that Darwin's version of natural selection was different from that presented by Wallace, in that Darwin held that natural selection was continuously operating whereas Wallace argued that selection only occurred when the environment changed. Also importantly, Wallace did not see any connection between selective breeding and natural selection. For Darwin this was a key difference: selective breeding and artificial selection were key inspirations for the processes which may go on in nature. On Wallace's own first edition of The Origin of Species, he crossed out every instance of the phrase "natural selection" and replaced with it Spencer's "survival of the fittest."

Darwin is included in the top 10 of the 100 Greatest Britons poll sponsored by the BBC and voted for by the public.

Philosophical implications

According to Mayr, Darwin's evolutionary thinking rests on a rejection of essentialism, which assumes the existence of some perfect, essential form for any particular class of existent, and treats differences between individuals as imperfections or deviations away from the perfect essential form. Darwin embraced instead what Mayr calls population thinking, which denies the existence of any essential form and holds that a class is the conceptualization of the numerous unique individuals. Individuals, in short, are real in an objective sense, while the class is an abstraction, an artefact of epistemology. This emphasis on the importance of individual differences is, of course, necessary if we are to believe that the mechanism of evolution, natural selection, operates on individual differences.

Mayr claims essentialism had dominated Western thinking for two thousand years, and that Darwin's theories thus represent an important and radical break from traditional Western philosophy. Ripples of Darwin's thought can now be seen in fields such as economics and complexity theory, suggesting that Darwin's influence extends well beyond the field of biology.

As an interesting aside, Darwin could be regarded as the first organism in four billion years of life on earth to realise how he had come to exist.

Views on religion

See Charles Darwin's views on religion.

Social Darwinism

A version of natural selection was also applied to human society (politics, economics, etc.). The most famous of these doctrines is Social Darwinism, a term that first appeared about 1900, where the rule of the strong is justified by claims that it merely reproduces in society Nature's rule that the fittest survive. It is commonly stated that Darwin never advocated such a philosophy. In his journals, he did evince great sympathy for enslaved or oppressed people and looked forward to a day when his Victorian concept of knowledge and enlightenment would bring civilization to all men.

Legacy

Charles Darwin's theory of evolution based upon natural selection changed the thinking of countless fields of study from biology to anthropology. His work was extremely controversial by the time he published it and many during his time didn't take it seriously. Darwin's theory of evolution was a significant blow to creationism and notions of intelligent design prevalant among 19th century Europe.

In his homeland Darwin appears on the Bank of England's ten-pound note. In Australia's Northern Territory there is a city, a university and a national park named for Darwin's 1839 visit there.

References

Works of Charles Darwin:

See also

External links

Wikiquote has a collection of quotations by or about Charles Darwin.


Wikisource has original works written by or about Charles Darwin.</div>
Basic topics in evolutionary biology
Processes of evolution: macroevolution - microevolution - speciation
Mechanisms: selection - genetic drift - gene flow - mutation
History: Charles Darwin - The Origin of Species - modern evolutionary synthesis
Subfields: population genetics - ecological genetics - molecular evolution - phylogenetics - systematics - evo-devo
List of evolutionary biology topics | Timeline of evolution


Charles Darwin Topics relating to Charles Darwin
Family: Erasmus Darwin (grandfather) - Josiah Wedgwood (maternal grandfather) - Emma Darwin (wife) - William Darwin; Anne Darwin; Etty Darwin; George Darwin; Elizabeth Darwin;

Francis Darwin; Leonard Darwin; Horace Darwin; Charles Waring Darwin (children) - Francis Galton (cousin)

Contributions to evolutionary biology: Evolution by means of natural and sexual selection.
Books: The Voyage of the Beagle - The Origin of Species - The Descent of Man and Selection in Relation to Sex
Named in honour of Darwin: Darwin Medal - Darwin, Australia - Charles Darwin University, Darwin College, Cambridge





ca:Charles Robert Darwin cy:Charles Darwin da:Charles Darwin de:Charles Darwin et:Charles Darwin es:Charles Darwin eo:Charles DARWIN fr:Charles Darwin gl:Charles Robert Darwin hr:Charles Darwin it:Charles Darwin la:Carolus Darwin ms:Charles Darwin nl:Charles Darwin ja:チャールズ・ダーウィン pl:Karol Darwin pt:Charles Darwin ro:Charles Darwin ru:Дарвин, Чарлз sl:Charles Darwin fi:Charles Darwin sv:Charles Darwin zh:查尔斯·罗伯特·达尔文

Retrieved from "http://www.centipedia.com/articles/Charles_Darwin"

This page has been accessed 4710 times. This page was last modified 16:36, 24 Nov 2004. All text is available under the terms of the GNU Free Documentation License (see Copyrights for details).