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Charles Darwin and His
Origin of Species
Darwin’s Background
• Born in England, 1809 • Studied Medicine at
Edinburgh University• Transferred to
Cambridge University• Studied to be a Minister
Library of Congress, Prints and Photographs Division [reproduction number, e.g., LC-USZ61-104].
Darwin’s Expedition - 1831
• Hired as Naturalist on H.M.S. Beagle
• Sailed on Five Year Scientific Expedition– Down East Coast of South America– Up Pacific Coast to Galapagos
Islands– Made Stops on Mainland and Islands– Observed Variety of Life and
Habitats
Darwin’s Work
• Outlined Theory in his Book in 1859:– On the Origin of Species by
Means of Natural Selection
• Published Other Works on Biology • Died in 1882
Summary of Origin of Species
• Proposed Evolution Resulting from Natural Selection:– Organisms Produce Many Offspring– Competition for Food, Territory, Mates, etc.– Those With Best Traits Survive – Organisms Change Over Many Generations
• Time Frame: Millions of Years
Darwin’s Support for His Theory
• Characteristics of Organisms Coincide With Habitats
• Changes Produced by Breeding of Organisms
• Geologic Ages Suggested by Charles Lyell
• Similarities of Various Organisms
Limitations of Darwin’s Theory
• Apparent Limits to Variation • No Mechanism For Sufficiently New
Characteristics• Transitional Forms Would Require
Special Environments• Oversimplified View of Living Cells• The Origin of Life Unexplained• Limitations of Fossil Record
• Sudden Appearance of Complex Life
• Lack of Clear Transitional Forms• Gives More Evidence For Species
Disappearance
Limitations of the Fossil Record
Chicago Daily News negatives collection, DN-0006585. Courtesy of the Chicago Historical Society. American Memory Collection
• Sudden Appearance of Complex Life
• Lack of Clear Transitional Forms• Gives More Evidence For Species
Disappearance • Explanation of Strata Insufficient
Limitations of the Fossil Record
Limitations of the Fossil Record
Bryce Canyon, Utah Fossils on Display Western History/Genealogy Department, Denver Public Library, American Memory Collection
Strata Better Explained by Hydrologic Catastrophe
• Magnitude of Fossil Graveyards
Strata Better Explained by Hydrologic Catastrophe
Petrified forestAmerican Environmental Photographs Collection, [AEP Image Number, e.g., AEP-AZS8], Department of Special Collections, University of Chicago Library, American Memory Collection.
Strata Better Explained by Hydrologic Catastrophe
• Magnitude of Fossil Graveyards• Polystrate Fossils
Strata Better Explained by Hydrologic Catastrophe
American Environmental Photographs Collection, [AEP Image Number, e.g., AEP-WYS32], Department of Special Collections, University of Chicago Library, American Memory Collection.
VerticalFossilTrees
Strata Better Explained by Hydrologic Catastrophe
• Magnitude of Fossil Graveyards• Polystrate Fossils• Inconsistent Fossil Distribution
Strata Better Explained by Hydrologic Catastrophe
• Magnitude of Fossil Graveyards• Polystrate Fossils• Inconsistent Fossil Distribution• Fossils Found Together From
Separate Ages
Strata Better Explained by Hydrologic Catastrophe
• Magnitude of Fossil Graveyards• Polystrate Fossils• Inconsistent Fossil Distribution• Fossils Found Together From
Separate Ages• Simple (“Older”) Organisms Above
Complex (“Younger”)
Scientists’ Initial Reactions to Darwin’s Work
• A Compilation of Assertions and Hypotheses
• Unsupported by Scientific Testing• Contains Assumptions that Cannot
Be Supported• Violates the Principles of Cause
and Effect• Illogical Conclusions
So Why Was It Eventually Accepted?
• It Passed Rigorous Scientific Testing?– No, His Hypotheses Are Not Testable
• Were Transitional Fossils Found?– No Clearly Substantiated Links Found Yet
• A Mechanism to Produce New Traits Discovered?– Mutations Result in Lost Genetic Information
The Acceptance of Darwin’s Theory of Evolution
• Natural Selection of Genetic Variations is Observable– Limited to Genes Already Present– New Traits Produced Only By
Mutations– Overwhelming Odds Against Good
Mutations
Ultimately, Acceptance Depended On One Factor:
Willingness to Accept a Naturalistic Explanation
Credits• All clip art is from ClickArt by Broderbund• All photographs were accessed through the
Library of Congress American Memory Collection.
• The Darwin photograph is from Library of Congress, Prints and Photographs Division.
• The dinosaur fossil photo is from the Chicago Daily News negatives collection, Courtesy of the Chicago Historical Society.
• The Bryce Canyon and fossil display photos are from the Western History/Genealogy Department, Denver Public Library.
• The fossil trees and Petrified Forest photos are from the American Environmental Photographs Collection, Department of Special Collections, University of Chicago Library.