BIOL 112 1st Edition Lecture 5 Outline of Last Lecture I What Do We See in Fossils II Anatomical Evidence III Interpretation of Homology IV Vestigial Organs V Embryology A What does it mean VI Molecular Homologies VII Interpretations A Theories of Evolution VIII St Augustine of Hippo A Problems with Augustine Model IX The Enlightenment X Jean Baptiste Lamarck A Examples of Lamarck s Model B Tests of Lamarck s Model XI Charles Darwin 1809 1882 Current Lecture XII Voyage of the H M S Beagle A Observations XIII Post Voyage XIV Alfred Russel Wallace 1823 1913 These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute XV Factors that Influenced Darwin XVI Darwin s Thinking Process A Three Observations B Two Conclusions XVII What we Know Now XVIII Darwinian Evolution XIX Tests of Darwin s Theory XX Moth Selection XXI Selection in Action Penicillin XXII Natural Selection in Action XXIII Sphecomyrma XXIV Tiktaalik XXV Archeopteryx XXVI Other Phenomena A Moth Bee Mimicry B M llerian Mimicry XXVII Status of Darwin s Theory Current Lecture I Voyage of the H M S Beagle Major discovery and mapping expedition of South America Similar to moon exploration now Scientific work of the highest quality Lasted 5 years Headed by Capt Robert FitzRoy 1805 1865 Youngest Captain in the British Navy at the time Excellent mariner administrator navigator Later Governor of New Zealand Colony for 2 years eventually promoted to Admiral Methodical careful scientist reputation as a surveyor navigator meteorologist Moody depressed man later committed suicide Darwin was also to be a gentleman companion to FitzRoy someone in the same social class to talk to Both were educated upper middleclass gentlemen Both lived in the same 9 x 12 cabin with a mass of scientific instruments clocks and books Frequent trouble FitzRoy had a temper Darwin and FitzRoy had divergent political and religious views Discussions turned into debates and debates sometimes turned into quarrels Frequent debates and arguments forced Darwin to think through his ideas and justify his own views Darwin collected animals plants rocks fossils all along coast Observed cultures and activities of peoples along coast Sent specimens and reports home winning him a growing reputation as a good scientist A Observations Gal pagos Islands 800 mi west of Ecuador Chain of volcanic islands each about 20 50 mi from the others Strange collection of creatures there Darwin s Finches 13 species distributed among various specific islands All similar but all distinct in size and behavior many doing things that finches don t do carrion eaters insect eaters fruit etc But only 1 species of finch throughout South American mainland seed eater This bothered Darwin why only 1 species on mainland but 13 distinct species crammed on small islands And why were island finches doing things that finches don t normally do XIII Post Voyage 1836 Returned to Great Britain Wrote his parts of a multi volume Beagle voyage report Elected Secretary of Royal Geological Society Important and respected naturalist 1838 Married a cousin but never did become a clergyman Father gave up and gave him an endowment Lived in Down House 16 mi SE of London for the rest of his life as a gentleman scientist Was chronically ill much of the rest of his life Kept very elaborate diaries and notebooks records of thoughts experiments observations activities so we can reconstruct what he was thinking about and when Through late 1830s into 1840s developed a radical theory of evolution 1842 summary of thoughts written in notebook 1844 essay never published hesitated to publish anything about this until he had accumulated enough evidence to support his theory Waited for 20 years Very active otherwise Many books and papers world expert on coral reef formation barnacles pigeon breeding etc Continued as Secretary of Royal Geological Society Might never have published his theory except for the work of another scientist XIV Alfred Russel Wallace 1823 1913 Wallace was a scientist and professional collector in a biological field station research institute in New Guinea in the 1850s Had independently developed evolutionary theory nearly identical to that of Darwin In 1858 he wrote a short paper on evolution and sent it to Darwin asking for help in getting it published Darwin was going to publish Wallace s paper and give him full credit but Darwin s friends persuaded him to publish a joint paper co authored with Wallace on the theory in 1858 1859 Darwin assembled his 20 years of thinking and assembly of evidence in an abbreviated work The Origin of Species First edition sold out in one day Major paradigm changed scientific opinions and started studies and experimental investigations which continue today XV Factors that Influenced Darwin 1 Lamarck Evolution does occur new species do appear in the history of life Organisms do change and a theory describing the mechanism is possible 2 Charles Lyell 1797 1875 Geologist developed Theory of Uniformitarianism Geological activities seen today slow erosion mountain building can explain major features Planet is ancient Lyell s work gave Darwin the geological time slow geological evolution within which slow biological evolution could occur 3 Thomas Malthus 1766 1834 Gloomy mathematician economist clergyman Wrote a book against social welfare programs in 1798 argued mathematically that populations always eventually exceed food supplies so periodic famines are inevitable 4 Selective Animal Plant Breeding Darwin was a breeder of fancy pigeons corresponded with farmers and hobby breeders Saw how diverse plants and animals can be developed from an ancestor by highly selective breeding and how fast those changes can be achieved XVI Darwin s Thinking Process Observed changes descent with modification evolution How All organisms are a little different from one another variability in population Resources are limited for organisms Malthus Therefore not all organisms will succeed and reproduce in the competition for limited resources Who reproduces better Those organisms with variations giving them better abilities to compete for limited resources whatever those might be Variations have a genetic basis observations of breeding programs Therefore those organisms who do reproduce better have genetic combinations giving them the better abilities to compete for resources And they will pass on those combinations