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Recommended for: Grades 9-12

Resource: Complex Relations

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In this text excerpted from chapter 3, "Struggle for Existence," of Charles Darwin's On the Origin of Species, Darwin draws on firsthand and historical information for his observations about evolution.

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Teachers' Domain, Complex Relations, published September 26, 2003, retrieved on ,
http://www.teachersdomain.org/resource/tdc02.sci.life.evo.complexrelat/

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This text is excerpted from Charles Darwin's On the Origin of Species by Means of Natural Selection. Drawing on research and personal observation, Darwin examines the "mutual relations of all organic beings." Through his study of competition and cooperation among plant and animal species shaped by environmental factors, Darwin describes the forces that drive evolution.