Download The 2 fundamental questions: Linneaus and Kirchner

2/1/2011
The 2 fundamental questions:
Section 4
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y Has evolution taken place, and if so, what is the evidence?
Professor Donald McFarlane
y If evolution has taken place, what is the mechanism by Lecture 2
Evolutionary Ideas
Evidence for evolution before Darwin
which it works?
Golden Age of Exploration
y Magellan’s voyage – 1519
y Antonius von Leeuwenhoek ‐ microbes – 1683
y John Ray – University of Cambridge (England)
y “Catalog of Cambridge Plants” –
1660 – lists 626 species
y 1686 – John Ray listing thousands of plant species!
y In 1678, Francis Willoughby publishes “Ornithology”
Linneaus and Kirchner
Athenasius Kircher ~ 1675 – Noah’s ark Carl Linneaus –
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Sistema Naturae ‐ 1735
Ark too small!!
Uses a ‘phenetic” classification –
implies a phylogenetic relationship!
300 x 50 x 30 cubits ~ 135 x 20 x 13 m 1
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y Georges Cuvier 1769‐ 1832
y “Fixity of Species”
Evidence for Evolution – prior to 1830
• Enormous diversity of life – WHY ??? JBS Haldane " The Creator, if He exists, has "an inordinate fondness for beetles" ".
Evidence for Evolution – prior to 1830
y The discovery of variation.
Evidence for Evolution – prior to 1830
y Comparative Anatomy.
Pentadactyl
limbs
Evidence for Evolution – prior to 1830
y Fossils – homologies with living species
Evidence for Evolution – prior to 1830
y Vestigal structures
Pentadactyl
limbs !!
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Evidence for Evolution – prior to 1830
y Invariance of the fossil sequence
Evidence for Evolution – prior to 1830
y Plant and animal breeding
JBS Haldane: I will give up my JBS Haldane: “I will give up my belief in evolution if someone finds a fossil rabbit in the Precambrian.”
Jean Baptiste Lamark
y 1744‐1829
y Organisms have the ability to adapt to their environments over the course of their lives.
y Organisms have the ability to pass on these ‘acquired characteristics’ to their offspring.
y Organisms have a built‐in “drive to perfection”
Alfred Russel Wallace
y 1823 – 1913
y Amazon 1848 ‐1852
y “Wallacea” 1854 ‐ 1862
Charles Darwin
y 1809 – 1882
y Voyage of Beagle 1831 ‐ 1836
y 1858 – The Linnaean Society
y Wallace’s Ternate paper +
y Darwin’s letter to Asa Gray
y 1859 – “Origin of Species”
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The 5 tenets of the Theory of Natural Selection
y All organisms show variation
y At least some variation is heritable
y All organisms produce more offspring than can survive
y Offspring with ‘favorable’ variations will have a better chance of survival and reproduction
y The ‘favorable’ variation will be more common in the next generation
The Modern Synthesis
y Early to mid‐20th Century
y RA Fisher ~ 1918 ‐ statistics
y JBS Haldane ~ 1924 – evolutionary genetics
y Sewall Wright – evolutionary genetics
y George Gaylord Simpson – paleontology
y Ernst Mayer – biogeography and speciation
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