Charles Darwin
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2 Journey on the Beagle 3 First writings 4 The Origin of Species 5 Before Darwin 6 Darwin's theory of evolution 7 Views on religion 8 See also 9 External links |
Early life
Charles Darwin was born in Shrewsbury, Shropshire, England, the fifth of six children of Robert and Susannah Darwin (née Wedgwood), and the grandson of Erasmus Darwin, and of Josiah Wedgwood.
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 Cambridge University, with the hopes of Charles' eventually becoming a parson. 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 honors, 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 gentleman's companion to Robert Fitzroy, the captain of the HMS Beagle, which was departing on a five-year expedition to chart the coastline of South America.
Journey on the Beagle
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.
During his voyage, he visited the Cape Verde Archipelago, the Falkland Islands, the South American coast, the Galapagos Islands, New Zealand and Australia, collecting considerable quantities of specimens.
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, favored 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.
First writings
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 would modify his theory in a number of ways.
Darwin published other treatises in science, including an explanation for the creation of coral atolls in the South Pacific, and the story of his voyage aboard the Beagle.
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). Darwin and his wife had ten children, three of whom died early. Between 1839 and 1843, Darwin's Zoology of the Voyage of H.M.S. Beagle was published in five volumes.
The Origin of Species
Darwin's work brought him a correspondence relationship with Alfred Russel Wallace, working in the islands of the South Pacific. In June, 1858, Wallace sought Darwin's ideas on a theory Wallace had developed which exactly mirrored Darwin's own work. Scientist friends persuaded Darwin to go public with the theory, now independently confirmed. On 1 July, 1858, Darwin's paper about The Origin of Species by Means of Natural Selection was read to the Linnean Society in London, jointly with Wallace's paper.
Darwin's book On the Origin of Species by Means of Natural Selection was published one year later, and was of sufficient interest to have the publisher's stocks completely sold to bookstores on the first day.
It provoked an outraged response from the Church. A large meeting was organised in Oxford where 'Soapy Sam' Wilberforce, the Bishop of Oxford, numerous Clergy and Robert Fitzroy (the Captain of HMS Beagle) argued against Darwin, Thomas Huxley and their Evolutionist supporters. On being asked by Wilberforce, whether he was descended from monkeys on his grandfather's side or his grandmother's side, Huxley, recognizing the stupidity of the question, 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.
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 value of Darwin's work was appreciated throughout the scientific community. 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
Darwin died in Downe, Kent, England, on 19 April 1882 was given a state funeral, and interred in Westminster Abbey near Isaac Newton.
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
Before the nineteenth century, the accepted theory for the extinction of species was called Catastrophism, which stated that species went extinct due to catastrophes that were often followed by the formation of new species ex nihilo (out of nothing). The extinct species can then be found as fossils. The new species were considered unchangeable. This theory was in accordance with the story of the Flood in the Bible. In the early nineteenth century, several new theories started to compete with Catastrophism. One of the most important ones was developed by Jean-Baptiste Lamarck (1744-1829). He observed that every new generation inherits the traits of its ancestors. He suggested that traits or organs become enhanced with repeated use and weakened or removed by disuse in each individual, who will pass these improvements or losses directly to their offspring. In 1830, the British geologist Sir Charles Lyell disproved the Catastrophism Theory, but held on to the theory of species staying unchanged during time. Lyell founded uniformitarianism, a theory stating that the surface of earth changed slowly through eons by constant forces.
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 (Fig. 2). 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.
Figure 2 : Schematic drawing of the evolution process.
(1) Natural selection. (2) Reproduction. (3) Mutation.
Response to Darwin's theory
After the publication of Darwin's book, evolution as the means of natural selection was widely discussed (Fig. 3), 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. 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. 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 amongst Western countries, do not do so on religious grounds. See Pseudoscience creationism.
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).
Other important aspects of Darwin's overall theory 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 he held that natural selection was continuously operating,
whereas Wallace argued that selection only occurred when the
environment changed.
Figure 3 : Caricature of Darwin as an ape in the Hornet magazine. (Image in the PD)
Darwin is included in the top 10 of the 100 Greatest Britons poll sponsored by the BBC and voted for by the public.
Views on religion
It has been falsely claimed that Darwin converted to Christianity on his deathbed. The claim can be dismissed by his never having renounced the church. This claim is discussed in The Survival of Charles Darwin: A Biography of a Man and an Idea, by Ronald W. Clark (Weidenfeld & Nicholson 1985), p. 199:
- "Shortly after his death, Lady Hope addressed a gathering
of young men and women at the educational establishment
founded by the evangelist Dwight Lyman Moody at Northfield,
Massachusetts. She had, she maintained, visited Darwin on
his deathbed. He had been reading the Epistle to the Hebrews,
had asked for the local Sunday school to sing in a summerhouse
on the grounds, and had confessed: 'How I wish I had not
expressed my theory of evolution as I have done.' He went
on, she said, to say that he would like her to gather a
congregation since he 'would like to speak to them of Christ
Jesus and His salvation, being in a state where he was eagerly
savouring the heavenly anticipation of bliss.'
- "With Moody's encouragement, Lady Hope's story was printed
in the Boston Watchman Examiner. The story spread, and the
claims were republished as late as October 1955 in the Reformation
Review and in the Monthly Record of the Free Church of Scotland
in February 1957. These attempts to fudge Darwin's story
had already been exposed for what they were, first by his
daughter Henrietta after they had been revived in 1922.
'I was present at his deathbed,' she wrote in the Christian
for February 23, 1922. 'Lady Hope was not present during
his last illness, or any illness. I believe he never even
saw her, but in any case she had no influence over him in
any department of thought or belief. He never recanted any
of his scientific views, either then or earlier. We think
the story of his conversion was fabricated in the U.S.A.
. . . The whole story has no foundation whatever.'" (Ellipsis
original.)
- "Ignorance more frequently begets confidence than does
knowledge: it is those who know little, and not those who
know much, who so positively assert that this or that problem
will never be solved by science."
- "Belief in God- Religion.- There is no evidence that
man was aboriginally endowed with the ennobling belief in
the existence of an Omnipotent God. On the contrary there
is ample evidence, derived not from hasty travellers, but
from men who have long resided with savages, that numerous
races have existed, and still exist, who have no idea of
one or more gods, and who have no words in their languages
to express such an idea. The question is of course wholly
distinct from that higher one, whether there exists a Creator
and Ruler of the universe; and this has been answered in
the affirmative by some of the highest intellects that have
ever existed."
- "The belief in God has often been advanced as not only
the greatest, but the most complete of all the distinctions
between man and the lower animals. It is however impossible,
as we have seen, to maintain that this belief is innate
or instinctive in man. On the other hand a belief in all-pervading
spiritual agencies seems to be universal; and apparently
follows from a considerable advance in man's reason, and
from a still greater advance in his faculties of imagination,
curiosity and wonder. I am aware that the assumed instinctive
belief in God has been used by many persons as an argument
for His existence. But this is a rash argument, as we should
thus be compelled to believe in the existence of many cruel
and malignant spirits, only a little more powerful than
man; for the belief in them is far more general than in
a beneficent Deity. The idea of a universal and beneficent
Creator does not seem to arise in the mind of man, until
he has been elevated by long-continued culture."
- "Whilst on board the Beagle (October 1836-January 1839)
I was quite orthodox, and I remember being heartily laughed
at by several of the officers (though themselves orthodox)
for quoting the Bible as an unanswerable authority on some
point of morality. I suppose it was the novelty of the argument
that amused them. But I had gradually come, by this time,
to see that the Old Testament; from its manifestly false
history of the world, with the Tower of Babel, the rainbow
as a sign, etc., etc., and from its attributing to God the
feelings of a revengeful tyrant, was no more to be trusted
than the sacred books of the Hindoos, or the beliefs of
any barbarian." (Charles Darwin: The Autobiography of Charles
Darwin with original omissions restored. New York, Norton,
1969. p.85)
- "By further reflecting that the clearest evidence would
be requisite to make any sane man believe in the miracles
by which Christianity is supported, --that the more we know
of the fixed laws of nature the more incredible, do miracles
become, --that the men at that time were ignorant and credulous
to a degree almost incomprehensible by us, --that the Gospels
cannot be proved to have been written simultaneously with
the events, --that they differ in many important details,
far too important as it seemed to me to be admitted as the
usual inaccuracies of eyewitness; --by such reflections
as these, which I give not as having the least novelty or
value, but as they influenced me, I gradually came to disbelieve
in Christianity as a divine revelation. The fact that many
false religions have spread over large portions of the earth
like wild-fire had some weight with me. Beautiful as is
the morality of the New Testament, it can hardly be denied
that its perfection depends in part on the interpretation
which we now put on metaphors and allegories." (p.86)
- "Thus disbelief crept over me at a very slow rate, but
at last was complete. The rate was so slow that I felt no
distress, and have never since doubted even for a single
second that my conclusion was correct." (p.87)
- "I can indeed hardly see how anyone ought to wish Christianity
to be true; for if so the plain language of the text seems
to show that the men who do not believe, and this would
include my Father, Brother and almost all my best friends,
will be everlastingly punished. And this is a damnable doctrine."
(p. 87)
- "The old argument of design in nature, as given by Paley,
which formerly seemed to me so conclusive, fails, now that
the law of natural selection had been discovered. We can
no longer argue that, for instance, the beautiful hinge
of a bivalve shell must have been made by an intelligent
being, like the hinge of a door by man. There seems to be
no more design in the variability of organic beings and
in the action of natural selection, than in the course which
the wind blows. Everything in nature is the result of fixed
laws." (p.87)
- "At the present day (ca. 1872) the most usual argument
for the existence of an intelligent God is drawn from the
deep inward conviction and feelings which are experienced
by moat persons. But it cannot be doubted that Hindoos,
Mahomadans and others might argue in the same manner and
with equal force in favor of the existence of one God, or
of many Gods, or as with the Buddists of no God...This argument
would be a valid one if all men of all races had the same
inward conviction of the existence of one God: but we know
that this is very far from being the case. Therefore I cannot
see that such inward convictions and feelings are of any
weight as evidence of what really exists." (p.91)
- "Nor must we overlook the probability of the constant
inculcation in a belief in God on the minds of children
producing so strong and perhaps as inherited effect on their
brains not yet fully developed, that it would be as difficult
for them to throw off their belief in God, as for a monkey
to throw off its instinctive fear and hatred of a snake."
(p.93)
See also
- DarwinWiki
- Charles Darwin University (proposed university, Australia)