History of Evolutionary Thought

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History of Evolutionary Thought

• The Biblical Perspective
• 17th Century Theories of the Earth
• Catastrophism and Uniformitarianism
• Physics and the Age of the Earth
• Diversity
• Before Darwin
• Charles Darwin (1809 1882)
• Darwins Other Big Idea
• The Modern Synthesis
• X. Modern Genetics

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I. The Biblical Perspective (Genesis)

1. Genesis Metaphoric until 17th Century

• Starting with Augustine

• Fundamentalist movement (early 1900s reaction
  against materialism and Higher Criticism)

B. Creation account in Genesis 1 1-3

• Days of Creation

Day one Heavens and Earth light day and night
Day two the Firmament waters divided
Day three waters and dry land organized plants
Day four Lights (stars) in the Firmament
Day five Sea creatures and birds
Day six Land animals man and woman
Day seven Rest and blessing last day holy
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Second Account Genesis 2 4-25
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I. The Biblical Perspective (Genesis)
C. The Flood (Genesis 6, 7, 9) ca 2500 BCE

• Geology

Before the Flood
After the Flood

• Diversity at Creation 30,000 Kinds

The passengers
Mt. Ararat
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II. Theories of the Earth
A. James Ussher (1581 1656) and the age of the
Earth
1. Based on Biblical chronologies and historical
records
2. 4004 BCE
B. Physical explanations for the Flood
1. Descartes Earth a dead star

• Flood from collapse of originally smooth surface

2. Newton flood from near collision with a comet
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II. Theories of the Earth
C. Theories on Fossils
1. Idealized forms
2. Mythological creatures
3. Organisms formed within the Earth, but didnt
make it
4. Sports of nature
5. Nicolas Steno (1638 1686)
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II. Theories of the Earth
D. Comte de Buffon (1707 1788)
1. Natural History

• Experimented with cooling of large spheres

• Calculated Earth to be 75, 000 years old

• Censured by the Church forced to recant

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II. Theories of the Earth
E. Stratigraphy
1. Three types of rocks

• Igneous from cooled magma

Granite

• Metamorphic transformed by pressure and heat

Gneiss

• Sedimentary from sediments

• Form in layers called strata

• Fossil bearing rock

Shale
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II. Theories of the Earth
E. Stratigraphy
2. Strata (stratum)

• Deposits from the Flood?

3. Stratigraphy important for mining, canal
building

• Led to classification of different strata
  sequences

• Principle of Superposition

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II. Theories of the Earth
E. Stratigraphy
4. Best method for identifying strata index
fossils
William Strata Smith (1769 - 1839)
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II. Theories of the Earth
E. Stratigraphy
1. Index fossils linked to Geologic Periods
2. Relative dating
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III. Catastrophism and Uniformitarianism
A. Catastrophism
1. Neptunists rocks formed from Flood
2. Georges Cuvier (1769 - 1832)

• Father of Paleontology

• Extinction!

• 5 major extinctions

• Each extinction followed by new assemblage of
  flora
• and fauna

• Cuviers explanation new assemblage by migration

• Boundaries abrupt sudden extinction caused by
• catastrophes

• Others last extinction (Cretaceous Triassic)
  was the caused by the Great Flood (not
  necessarily worldwide)

• Vehemently anti-evolution

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III. Catastrophism and Uniformitarianism
B. Uniformitarianism
1. Landforms created slowly by forces observable
today
2. James Hutton (1726 1797)
no vestige of a beginning, -- no prospect of an
end

• Plutonist rocks formed from Earths hot interior

• Closer to modern view

• Igneous rocks the starting
• point of the rock cycle

• Deist God is a perfect craftsman who designed a
• machine that could work forever

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B. Uniformitarianism
3. Charles Lyell (1797 1875)

• Principles of Geology

• Mount Aetna

• Strata below volcano

• Abrupt transitions in fossil record due to
  missing strata

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III. Catastrophism and Uniformitarianism
C. Modern View
1. Synthesis, but .
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III. Catastrophism and Uniformitarianism
C. Modern View
2. Plate tectonics and continental drift

• Alfred Wegener (1880- 1930)

• Sea floor spreading

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III. Catastrophism and Uniformitarianism
C. Modern View
3. Extinction

• 5 major extinctions

• Biggest extinction Permian 250 million years ago
  (mya)

• 70 of land vertebrate species

• Siberian Traps

• Cretaceous (65 mya)

• Meteor/ meteorite

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IV. Physics and the Age of the Earth
A. Lord Kelvin (1824 -1907)
1. Earth began as hot mass
2. Earth, at most, 25 million years old
B. Discovery of Radioactivity (1896)
1. Source of heat

• Drives Continental Drift

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IV. Physics and the Age of the Earth
B. Discovery of Radioactivity (1896)
2. Radioactive decay

• Radioactive isotopes decay from one type of atom
  to
• another

• C14 gtgtgt N14

Half- life 5730 years
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IV. Physics and the Age of the Earth
B. Discovery of Radioactivity (1896)
3. Absolute Time Scale (Geologic Time Scale)
4. Age of the Earth 4.55 billion years
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