Lecture Week 2

History of Evolution

1. Beginnings of Modern thought on human origins
   1. View in Europe Biblically based- Adam & Eve about 6000 yrs ago
   2. James Ussher, Archbishop of Armagh (Church of Ireland) figures 4004 BC; 1650
      1. Counted begats in Genesis & tied into other histories (Roman, Greek)
      2. Used logic, not faith
      3. This then included in Bibles, gains weight of authority
   3. Notion of "Great Chain of Being"
   4. Natural Theology- study of God's plan by studying nature
2. Hurdles to any theory of Evolution
   1. Age of Earth- Evolution needs time
   2. Fixity of species- Evolution postulates change
   3. All Scripture sacrosanct- Evolution contradicts literal interpretation of Bible
   4. Imprecise knowledge of nature & organisms- Evolution needed data to support it
3. The first hurdlers
   1. Carolus Linnaeus (1707-1778)
      1. Natural Philosophy
      2. Systemae Naturae, 1735 1st Ed., 1758 10th
      3. Binomial Classification System
         1. Nested hierarchies- ranks relationships
         2. Each species given unique name
         3. Type specimen (Holotype)
         4. Describe "killing features"- features unique to species
   2. Georges Leclerc, Comte de Buffon (1707-1788)
      1. Systematic description of nature
      2. Histoire Naturelle (Natural History)
      3. Early- Time depth & Common descent
      4. Later- Retraction & Religion
   3. James Hutton (1728-1799)
      1. Deep Time
      2. Uniformitarianism vs. Catastrophism
      3. Popularized by Charles Lyell- Principles of Geology 1830
   4. Jean Lamarck (1744-1829)
      1. Orthogenesis- Internal striving
      2. Great Chain of Being becomes an escalator- Spontaneous Generation
      3. Inheritance of Acquired Characteristics
      4. Evolution takes place at individual level
   5. Georges Cuvier (1769-1832)
      1. Comparative Anatomy- way animal behaved governed its shape
      2. Species fixed- how change when shaped for specific way of life?
      3. Reality of Fossils & extinctions
      4. Catastrophism & Special Creations
   6. Thomas Malthus (1766-1832)
      1. Struggle for existence
         1. Populations increase geometrically
         2. Resources increase arithmetically
      2. Survival of the fittest
      3. Essay on the Principles of Population 1837
4. Charles Darwin (1809-1882)
   1. Voyage of the Beagle
   2. The Origin of Species
      1. 5 Observations & 2 Inferences
      2. First set from Malthus
         1. O#1- Species over-produce
         2. O#2- Populations stable
         3. O#3- Food supply limited
         4. I#1- Struggle for existence
      3. Second set Darwin's
         1. O#4- Individuals not identical; variation w/in species
         2. O#5- Differences passed on; variation heritable
         3. I#2- The most favorable variations survive better
      4. Putting it together
         1. There will be Differential Reproductive Success- what counts is not survival but reproduction.
         2. Theory of Natural Selection
         3. Over time will lead to new Species
         4. Gradualism- nature doesn't make leaps
   3. Delay in publication
      1. Only Joseph Hooker & Charles Lyell know about theory
      2. Then comes Alfred Wallace, 1858, came up with same theory!
      3. Hooker & Lyell present both papers to Linnean Society
      4. Origin published 1859
   4. Reactions
      1. France- no big deal; already heard Cuvier & Lamarck
      2. England- Big debates; clergy vs. scientists & scientists vs. scientists
         1. Thomas Huxley biggest supporter "Darwin's Bulldog"
         2. Wallace not at forefront; more interested in collecting
         3. Darwin continues work- The Descent of Man in 1871
      3. Two soft spots
         1. How does inheritance work & where do variations come from?
         2. Where is "missing link"- human fossils?

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