Natural selection - the history of an idea

Natural selection - the history of an idea

• origin of species - Charles Darwin 
• 1859 sold out instantly. loads - controversy

• biological species concept = species - groups interbreeding natural populations - reproductively isolated - other groups

• "great chain of being" - Plato/Aristotle - smooth graduation between minerals+God
• judeo-christian - each organism individually created, point time. species = unchanging. relationship = creator same - each species

• natural theology - find meaning God - studying natural world
• William Paley 1802 - living things complicated = designed
• "Watchmaker analogy" - design implies designer

• Carolus Linnaeus - binomial system
• hierarchical classifications - species, genus, family, order, class, phylum, kingdom 
• Linnaeus 1st thought species were fixed - creation. later considered species within genus - arisen since creation

• relationships imply ancestry 
• family tree implies each branches - common ancestor - branches meet
• Erasmus Darwin view evolution - life striving improvement. Pioneers - industrial revolution - lunar society

• evolution = descent with modification 

• fossils - remains long extinct species
• Georges Cuvier - fossil flying reptile (pterosaur) = extinct species
• Cuvier - catastrophism - fossils extinct animals. Biblical flood

• James Ussher (Archbishop) - age earth - calculating genealogies old testament = created Sunday 23rd October 4004BC
• Charles Lyell - principles of geology - theory uniformitarianism = earth shaped gradual accumulation deposits forming rock - eroded. Processes balanced. age earth - millions years - scope evolution

• Jean-Baptiste Lamarck - evolution occurred by inheritance acquired characteristics
• theory derided - contemporary scientists. each cell contained information gained - lifetime - passed to offspring
• Weissmann's rat experiment - designed debunk Lamarck

• December 1831 - HMS Beagle set sail - map coast South America. Charles Darwin voyaged - naturalist+companion - captain 
  • earth very old
  • evolution = explanation fossil record+interrelatedness various organisms 
  • evolution still minority belief (Darwin didn't believe - transmutation 
  • no accepted way - evolution could occur

• succession of types led Darwin - reject fixity of species
• Richard Owen = foremost palaeontologist, Britain. Darwin's fossils of South American megafauna - related modern day armadillos+tree sloths
• Darwin later cited - evidence - descent with modification 

• Darwin collected specimens - Galapogas islands. told tortoises varied between islands. collected mockingbirds+finches - forgot label
• John Gould - ornithologist - discovered mockingbirds+finches = separate species

• Darwin noticed species on islands resembled - adjacent continent. species varied between adjacent islands 
• Galapagos = young volcanic islands

• Darwin returned - read - "Essay on the principle of population" 1798 - Thomas Malthus
• Malthus = concerned about unfettered growth - human population - saw animals+plants produce more offspring than survive - resource limitation
• population growth if left unchecked - mass starvation according - Malthus - population outstripped available resources

• Darwin's return - Britain - ket notebooks developing theories of transmutation of species
• began speculating about transmutation (evolution) of species - one species - another, over time
• Darwin confided - Charles Lyell, Joseph ******, TH Huxley

• 1830s+40s - huge political upheaval - chartist movement demanded universal suffrage+rights working classes. associated…