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Darwin and Evolution. Charles Darwin 1809-1882. Young Darwin. H.M.S. Beagle. Captain Fitzroy, commander of the Beagle.
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Darwin and Evolution Charles Darwin 1809-1882
Captain Fitzroy, commander of the Beagle. Very conscious of the stressful loneliness of command and of the suicide both of Captain Stokes and of his uncle Viscount Castlereagh, who had cut his own throat in 1822 while in government office, he approached Beaufort in August 1831 and asked him to find a suitable gentleman companion for the voyage. Such a companion should share his scientific tastes, make good use of the expedition's opportunities for naturalism research, dine with him as an equal, and provide a semblance of normal human friendship.[1] While those Beaufort first approached turned the opportunity down, FitzRoy eventually approved Charles Darwin for the position. Before they left England FitzRoy gave Darwin a copy of the first volume of Charles Lyell's Principles of Geology, a book the captain had read that explained terrestrial features as the outcome of a gradual process taking place over extremely long periods.
- The crew of the Beagle hailed by Fuegians of Jemmy Button's tribe. Orundellico, known as "Jemmy Button", (c.1815-1864) was a native Fuegian of the Yaghan (or Yamana) tribe from islands around Tierra del Fuego, in modern Chile and Argentina. He was brought to England by Captain FitzRoy on the HMS Beagle and became a celebrity for a period.
In 1830, Captain Robert FitzRoy, at the command of the first expedition of the famous Beagle, took a group of hostages from the Fuegian indigenous people after one of his boats was stolen. Jemmy Button was paid for with a mother of pearlbutton, hence his name. It is not clear whether his family willingly accepted the sale or he was simply abducted. FitzRoy decided to take four of the young Fuegian hostages all the way to England "to become useful as interpreters, and be the means of establishing a friendly disposition towards Englishmen on the part of their countrymen."[1] He seems to have shown great concern for the four, feeding them before his own officers and crew and intending them to be educated and Christianised so that they could improve the conditions of their kin. One year later, the Beagle returned the three surviving Fuegians home, still captained by FitzRoy and at great expense to himself. He took with him a young naturalist, Charles Darwin, in what was the second voyage of HMS Beagle. After initial difficulty recalling his language and customs, Jemmy was soon out of his European clothes and habits. A few months after his arrival, he was seen emaciated, naked save for a loincloth and long-haired. Nevertheless, he declined the offer to return to England, which Darwin conjectured was due to the presence of his "young and nice looking wife", Lassaweea. It appears that he and the others had taught their families some English
FitzRoy's account includes a section of Remarks with reference to the Deluge in which he admits that having read works "by geologists who contradict, by implication, if not in plain terms, the authenticity of the Scriptures" and "while led away by sceptical ideas" he had remarked to a friend that the vast plain of sedimentary material they were crossing "could never have been effected by a forty days' flood" indicating that in his "turn of mind and ignorance of scripture" he was willing to disbelieve the Biblical account. Concerned that such ideas might "reach the eyes of young sailors" he earnestly explains in great detail his renewed commitment to a literal reading of the Bible, with arguments that rock layers high in the mountains containing sea shells are actually proof of Noah's Flood and that the six days of creation could not have extended over aeons because the grass, herbs and trees would have died out during the long nights.[5] When The Origin of Species was published FitzRoy was dismayed and apparently felt guilty for his part in the theory's development. He was in Oxford on 30 June 1860 to present a paper on storms and attended the meeting of the British Association for the Advancement of Science at which Samuel Wilberforce attacked Darwin's theory. During the debate FitzRoy, seen as "a grey haired Roman nosed elderly gentleman", stood in the centre of the audience and "lifting an immense Bible first with both and afterwards with one hand over his head, solemnly implored the audience to believe God rather than man". As he admitted that The Origin of Species had given him "acutest pain", the crowd shouted him down
Alfred Wallace was a famous biologist and zoogeographer. He is known as the father of biogeography. Alfred Wallace was born in England 1823, and died in 1913. In 1848, he went on an expedition with Henry Walter Bates to the Amazon. Between 1854 and 1862 he conducted research on the Malay archipelago. During the expedition, he noticed striking zoological differences between animal species of Asia and Australia. He created an imaginary line called Wallace's Line to explain these differences. In a striking coincidence, in 1858 Wallace wrote to another British biologist named Charles Robert Darwin about his ideas of evolution. Darwin had come up with the same theory of evolution. In 1858 Wallace’s contribution was entitled “On the tendency of varieties to depart indefinitely from the original type”. His work describes the theory of natural selection.
Darwin’s Theory Species Over-reproduce + population sizes remain constant High mortality + universal variation Survival of most fit + environmental change change through time = Evolution
Problems How to reconstitute variation?? answer, comes after 1900 with discovery of genetics – see next lecture
Response to Darwin Fact of Evolution vs Theory of Evolution Theory = what was the mechanism? Fact = did evolution occur? Accepted by most soon after publication Fact accepted because it explained a lot of observations fossil record Neanderthals embryology transitional forms. Theodosius Dobzhansky: “Nothing makes sense except in the light of Evolution
Horse evolution, Western U.S.
The Theory: not proven due to lack of understanding of variation. • But: accepted anyway • Religious acceptance, the two revelations; the world and the book • Political acceptance; the “white man’s burden”, favored races • Social acceptance: Herbert Spencer and charity • Karl Marx and class struggle • 4. Economic acceptance: capitalism Backlash: cooperation vs competition = struggle for existence vs cooperation
Note: what does survival of the fittest mean?? • Nature red of tooth and claw = struggle? • Differential reproduction – having more offspring. • college professors vs “lower educational levels” • Los Angeles – Hispanic vs other Caucasians • - Israelis vs Palestinians • Is this good or bad?? Depends on the causes of differences between the groups • Are they different due to genes, or economics, or opportunities?
Scientific response to Darwin • Fact accepted quickly (except for a few) • Theory – With the discovery of Genetics (1900) = impressed by mutation • Hopeful monsters = new species or group in one generation without selection!! • Problems: • Monsters don’t mate • Monsters don’t function very well
Due to extra segment = hox gene duplication; can’ t fly = non functional
Early paleontologists questions: 1. rate appears to be constant 2. how can a small change be selected for?
Paleontology - rate of change through time appears constant a. – finalism b. VitalismIncorporates the idea that evolution has a goal towards which it is progressing (guess what that goal is!)
The Synthesis - 1945 – genetics and paleontology come together. • Genetics provides the variation – even small variation can be selected for • Selection (the environment) determines what survives. • Note: environmental change irregular • And: no goal or direction to evolution other than adaptation. • New concepts • Punctuated equilibrium = differences in rate. Fast and slow.
