Charles Darwin I | Biology

<!DOCTYPE html> <html lang="en" dir="ltr"> <head>  <meta http-equiv="X-UA-Compatible" content="ie=edge"> <meta charset="utf-8"> <base href="https://www.visionlearning.com"> <title>Charles Darwin I | Biology | Visionlearning</title> <link rel="canonical" href="https://www.visionlearning.com/en/library/biology/2/charles-darwin-i/110"> <meta name="description" content="Learn about how Charles Darwin’s experiences and observations helped him develop a comprehensive theory of evolution through natural selection."> <meta name="keywords" content="how does experience effect science, what is evolution, how is natural selection different from adaptation, effect of Origin of Species on science, effect of science on religion"> <meta name="viewport" content="width=device-width, initial-scale=1.0, shrink-to-fit=no"> <meta name="msvalidate.01" content="D8E20F39AD48052260032E56DE409970"> <script type="application/ld+json"> { "@context": "http://schema.org/", "@type": "Article", "mainEntityOfPage": { "@type": "WebPage", "@id": "https://visionlearning.com/en/library/biology/2/charles-darwin-i/110" }, "name": "Charles Darwin I", "headline": "Charles Darwin I: The Origin of Species", "author": { "@type": "Person", "name": "Alfred L. Rosenberger, Ph.D." }, "datePublished": "2003-12-09 16:14:17", "dateModified": "2017-02-12T08:30:00+05:00", "image": { "@type": "ImageObject", "url": "/img/library/moduleImages/featured_image_110-23061209063142.jpeg", "width": 696, "height": 464 }, "publisher": { "@type": "Organization", "name": "Visionlearning, Inc.", "logo": { "@type": "ImageObject", "url": "http://visionlearning.com/images/logo.png", "width": 278, "height": 60 } }, "description": "The experiences and observations of Charles Darwin significantly contributed to his theory of evolution through natural selection. This module explores those influences and describes evolution as a force for biological change and diversification. The first in a series, it details how the theory challenged the cultural mindset of the time, including the effect of his major works: <em>On the Origin of Species by Means of Natural Selection</em> and <em>Sexual Selection and the Descent of Man.</em>", "keywords": "how does experience effect science, what is evolution, how is natural selection different from adaptation, effect of Origin of Species on science, effect of science on religion", "inLanguage": { "@type": "Language", "name": "English", "alternateName": "en" }, "copyrightHolder": { "@type": "Organization", "name": "Visionlearning, Inc." }, "copyrightYear": "2003"} </script> <meta property="og:url" content="https://visionlearning.com/en/library/biology/2/charles-darwin-i/110"> <meta property="og:title" content="Charles Darwin I | Biology | Visionlearning" /> <meta property="og:type" content="website"> <meta property="og:site_name" content="Visionlearning"> <meta property="og:description" content="Learn about how Charles 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Periodic Table of Elements II</a></li> <li><a href="/en/library/chemistry/1/the-periodic-table-of-elements-iii/297">The Periodic Table of Elements III</a></li> <li><a href="/en/library/chemistry/1/the-periodic-table-of-elements-iv/298">The Periodic Table of Elements IV</a></li> <li><a href="/en/library/chemistry/1/the-periodic-table-of-elements-v/299">The Periodic Table of Elements V</a></li> <li><a href="/en/library/chemistry/1/atomic-theory-i/50">Atomic Theory I</a></li> <li><a href="/en/library/chemistry/1/atomic-theory-ii/51">Atomic Theory II</a></li> <li><a href="/en/library/chemistry/1/atomic-theory-iii/223">Atomic Theory III</a></li> <li><a href="/en/library/chemistry/1/atomic-theory-iv/231">Atomic Theory IV</a></li> <li><a href="/en/library/chemistry/1/the-mole-and-atomic-mass/53">The Mole and Atomic Mass</a></li> </ul> </div> <button class="accordion__button" id="acc-button-physical-states-and-properties" data-accordion="button" 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</button> <div class="accordion__panel" id="acc-panel-hazards" data-accordion="panel" aria-labelledby="acc-button-hazards" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/earth-science/6/natural-hazards-and-risk/288">Natural Hazards and Risk</a></li> </ul> </div> <button class="accordion__button" id="acc-button-earth-history" data-accordion="button" aria-controls="acc-panel-earth-history" aria-expanded="false"> <span class="accordion__button__label"> Earth History </span> </button> <div class="accordion__panel" id="acc-panel-earth-history" data-accordion="panel" aria-labelledby="acc-button-earth-history" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/earth-science/6/extinction/295">Extinction</a></li> <li><a href="/en/library/earth-science/6/mass-extinctions/294">Mass Extinctions</a></li> </ul> </div> </div> </div> <button class="accordion__button" id="acc-button-environmental-science" data-accordion="button" 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Services</a></li> <li><a href="/en/library/environmental-science/61/population-biology/287">Population Biology</a></li> </ul> </div> <button class="accordion__button" id="acc-button-earth-cycles" data-accordion="button" aria-controls="acc-panel-earth-cycles" aria-expanded="false"> <span class="accordion__button__label"> Earth Cycles </span> </button> <div class="accordion__panel" id="acc-panel-earth-cycles" data-accordion="panel" aria-labelledby="acc-button-earth-cycles" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/environmental-science/61/the-nitrogen-cycle/98">The Nitrogen Cycle</a></li> <li><a href="/en/library/environmental-science/61/the-carbon-cycle/95">The Carbon Cycle</a></li> <li><a href="/en/library/environmental-science/61/the-phosphorus-cycle/197">The Phosphorus Cycle</a></li> </ul> </div> <button class="accordion__button" id="acc-button-scientific-research" data-accordion="button" aria-controls="acc-panel-scientific-research" aria-expanded="false"> <span class="accordion__button__label"> Scientific Research </span> </button> <div class="accordion__panel" id="acc-panel-scientific-research" data-accordion="panel" aria-labelledby="acc-button-scientific-research" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/environmental-science/61/collaborative-research-in-the-arctic-towards-understanding-climate-change/183">Collaborative Research in the Arctic Towards Understanding Climate Change</a></li> <li><a href="/en/library/environmental-science/61/atmospheric-chemistry-research-that-changed-global-policy/211">Atmospheric Chemistry Research that Changed Global Policy</a></li> </ul> </div> </div> </div> <button class="accordion__button" id="acc-button-general-science" data-accordion="button" aria-controls="acc-panel-general-science" aria-expanded="false"> <span class="accordion__button__label"> General Science </span> </button> <div class="accordion__panel" id="acc-panel-general-science" data-accordion="panel" aria-labelledby="acc-button-general-science" role="region"> <div class="accordion accordion--secondary"> <button class="accordion__button" id="acc-button-methods" data-accordion="button" aria-controls="acc-panel-methods" aria-expanded="false"> <span class="accordion__button__label"> Methods </span> </button> <div class="accordion__panel" id="acc-panel-methods" data-accordion="panel" aria-labelledby="acc-button-methods" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/general-science/3/the-scientific-method/45">The Scientific Method</a></li> </ul> </div> <button class="accordion__button" id="acc-button-measurement" data-accordion="button" aria-controls="acc-panel-measurement" aria-expanded="false"> <span class="accordion__button__label"> Measurement </span> </button> <div class="accordion__panel" id="acc-panel-measurement" data-accordion="panel" aria-labelledby="acc-button-measurement" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/general-science/3/the-metric-system/47">The Metric System</a></li> </ul> </div> <button class="accordion__button" id="acc-button-physical-properties" data-accordion="button" aria-controls="acc-panel-physical-properties" aria-expanded="false"> <span class="accordion__button__label"> Physical Properties </span> </button> <div class="accordion__panel" id="acc-panel-physical-properties" data-accordion="panel" aria-labelledby="acc-button-physical-properties" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/general-science/3/temperature/48">Temperature</a></li> <li><a href="/en/library/general-science/3/density-and-buoyancy/37">Density and Buoyancy</a></li> </ul> </div> </div> </div> <button class="accordion__button" id="acc-button-math-in-science" data-accordion="button" aria-controls="acc-panel-math-in-science" aria-expanded="false"> <span class="accordion__button__label"> Math in Science </span> </button> <div class="accordion__panel" id="acc-panel-math-in-science" data-accordion="panel" aria-labelledby="acc-button-math-in-science" role="region"> <div class="accordion accordion--secondary"> <button class="accordion__button" id="acc-button-equations" data-accordion="button" aria-controls="acc-panel-equations" aria-expanded="false"> <span class="accordion__button__label"> Equations </span> </button> <div class="accordion__panel" id="acc-panel-equations" data-accordion="panel" aria-labelledby="acc-button-equations" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/math-in-science/62/unit-conversion/144">Unit Conversion</a></li> <li><a href="/en/library/math-in-science/62/linear-equations/194">Linear Equations</a></li> <li><a href="/en/library/math-in-science/62/exponential-equations-i/206">Exponential Equations I</a></li> <li><a href="/en/library/math-in-science/62/exponential-equations-ii/210">Exponential Equations II</a></li> <li><a href="/en/library/math-in-science/62/scientific-notation/250">Scientific Notation</a></li> <li><a href="/en/library/math-in-science/62/measurement/257">Measurement</a></li> </ul> </div> <button class="accordion__button" id="acc-button-statistics" data-accordion="button" aria-controls="acc-panel-statistics" aria-expanded="false"> <span class="accordion__button__label"> Statistics </span> </button> <div class="accordion__panel" id="acc-panel-statistics" data-accordion="panel" aria-labelledby="acc-button-statistics" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/math-in-science/62/introduction-to-descriptive-statistics/218">Introduction to Descriptive Statistics</a></li> <li><a href="/en/library/math-in-science/62/introduction-to-inferential-statistics/224">Introduction to Inferential Statistics</a></li> <li><a href="/en/library/math-in-science/62/statistical-techniques/239">Statistical Techniques</a></li> </ul> </div> <button class="accordion__button" id="acc-button-trigonometric-functions" data-accordion="button" aria-controls="acc-panel-trigonometric-functions" aria-expanded="false"> <span class="accordion__button__label"> Trigonometric Functions </span> </button> <div class="accordion__panel" id="acc-panel-trigonometric-functions" data-accordion="panel" aria-labelledby="acc-button-trigonometric-functions" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/math-in-science/62/wave-mathematics/131">Wave Mathematics</a></li> </ul> </div> </div> </div> <button class="accordion__button" id="acc-button-physics" data-accordion="button" aria-controls="acc-panel-physics" aria-expanded="false"> <span class="accordion__button__label"> Physics </span> </button> <div class="accordion__panel" id="acc-panel-physics" data-accordion="panel" aria-labelledby="acc-button-physics" role="region"> <div class="accordion accordion--secondary"> <button class="accordion__button" id="acc-button-light-and-optics" data-accordion="button" aria-controls="acc-panel-light-and-optics" aria-expanded="false"> <span class="accordion__button__label"> Light and Optics </span> </button> <div class="accordion__panel" id="acc-panel-light-and-optics" data-accordion="panel" aria-labelledby="acc-button-light-and-optics" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/physics/24/the-nature-of-light/132">The Nature of Light</a></li> <li><a href="/en/library/physics/24/electromagnetism-and-light/138">Electromagnetism and Light</a></li> </ul> </div> <button class="accordion__button" id="acc-button-mechanics" data-accordion="button" aria-controls="acc-panel-mechanics" aria-expanded="false"> <span class="accordion__button__label"> Mechanics </span> </button> <div class="accordion__panel" id="acc-panel-mechanics" data-accordion="panel" aria-labelledby="acc-button-mechanics" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/physics/24/defining-energy/199">Defining Energy</a></li> <li><a href="/en/library/physics/24/waves-and-wave-motion/102">Waves and Wave Motion</a></li> <li><a href="/en/library/physics/24/gravity/118">Gravity</a></li> <li><a href="/en/library/physics/24/thermodynamics-i/200">Thermodynamics I</a></li> </ul> </div> </div> </div> <button class="accordion__button" id="acc-button-process-of-science" data-accordion="button" aria-controls="acc-panel-process-of-science" aria-expanded="false"> <span class="accordion__button__label"> Process of Science </span> </button> <div class="accordion__panel" id="acc-panel-process-of-science" data-accordion="panel" aria-labelledby="acc-button-process-of-science" role="region"> <div class="accordion accordion--secondary"> <button class="accordion__button" id="acc-button-introduction" data-accordion="button" aria-controls="acc-panel-introduction" aria-expanded="false"> <span class="accordion__button__label"> Introduction </span> </button> <div class="accordion__panel" id="acc-panel-introduction" data-accordion="panel" aria-labelledby="acc-button-introduction" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/process-of-science/49/the-process-of-science/176">The Process of Science</a></li> </ul> </div> <button class="accordion__button" id="acc-button-the-culture-of-science" data-accordion="button" aria-controls="acc-panel-the-culture-of-science" aria-expanded="false"> <span class="accordion__button__label"> The Culture of Science </span> </button> <div class="accordion__panel" id="acc-panel-the-culture-of-science" data-accordion="panel" aria-labelledby="acc-button-the-culture-of-science" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/process-of-science/49/the-nature-of-scientific-knowledge/185">The Nature of Scientific Knowledge</a></li> <li><a href="/en/library/process-of-science/49/scientists-and-the-scientific-community/172">Scientists and the Scientific Community</a></li> <li><a href="/en/library/process-of-science/49/scientific-ethics/161">Scientific Ethics</a></li> <li><a href="/en/library/process-of-science/49/scientific-institutions-and-societies/162">Scientific Institutions and Societies</a></li> </ul> </div> <button class="accordion__button" id="acc-button-ideas-in-science" data-accordion="button" aria-controls="acc-panel-ideas-in-science" aria-expanded="false"> <span class="accordion__button__label"> Ideas in Science </span> </button> <div class="accordion__panel" id="acc-panel-ideas-in-science" data-accordion="panel" aria-labelledby="acc-button-ideas-in-science" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/process-of-science/49/theories-hypotheses-and-laws/177">Theories, Hypotheses, and Laws</a></li> <li><a href="/en/library/process-of-science/49/scientific-controversy/181">Scientific Controversy</a></li> <li><a href="/en/library/process-of-science/49/creativity-in-science/182">Creativity in Science</a></li> </ul> </div> <button class="accordion__button" id="acc-button-research-methods" data-accordion="button" aria-controls="acc-panel-research-methods" aria-expanded="false"> <span class="accordion__button__label"> Research Methods </span> </button> <div class="accordion__panel" id="acc-panel-research-methods" data-accordion="panel" aria-labelledby="acc-button-research-methods" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/process-of-science/49/the-practice-of-science/148">The Practice of Science</a></li> <li><a href="/en/library/process-of-science/49/experimentation-in-scientific-research/150">Experimentation in Scientific Research</a></li> <li><a href="/en/library/process-of-science/49/description-in-scientific-research/151">Description in Scientific Research</a></li> <li><a href="/en/library/process-of-science/49/comparison-in-scientific-research/152">Comparison in Scientific Research</a></li> <li><a href="/en/library/process-of-science/49/modeling-in-scientific-research/153">Modeling in Scientific Research</a></li> </ul> </div> <button class="accordion__button" id="acc-button-data" data-accordion="button" aria-controls="acc-panel-data" aria-expanded="false"> <span class="accordion__button__label"> Data </span> </button> <div class="accordion__panel" id="acc-panel-data" data-accordion="panel" aria-labelledby="acc-button-data" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/process-of-science/49/data-analysis-and-interpretation/154">Data Analysis and Interpretation</a></li> <li><a href="/en/library/process-of-science/49/uncertainty-error-and-confidence/157">Uncertainty, Error, and Confidence</a></li> <li><a href="/en/library/process-of-science/49/statistics-in-science/155">Statistics in Science</a></li> <li><a href="/en/library/process-of-science/49/using-graphs-and-visual-data-in-science/156">Using Graphs and Visual Data in Science</a></li> </ul> </div> <button class="accordion__button" id="acc-button-scientific-communication" data-accordion="button" aria-controls="acc-panel-scientific-communication" aria-expanded="false"> <span class="accordion__button__label"> Scientific Communication </span> </button> <div class="accordion__panel" id="acc-panel-scientific-communication" data-accordion="panel" aria-labelledby="acc-button-scientific-communication" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/process-of-science/49/understanding-scientific-journals-and-articles/158">Understanding Scientific Journals and Articles</a></li> <li><a href="/en/library/process-of-science/49/utilizing-the-scientific-literature/173">Utilizing the Scientific Literature</a></li> <li><a href="/en/library/process-of-science/49/peer-review-in-scientific-publishing/159">Peer Review in Scientific Publishing</a></li> <li><a href="/en/library/process-of-science/49/the-how-and-why-of-scientific-meetings/186">The How and Why of Scientific Meetings</a></li> </ul> </div> </div> </div> <button class="accordion__button" id="acc-button-scientists-and-research" data-accordion="button" aria-controls="acc-panel-scientists-and-research" aria-expanded="false"> <span class="accordion__button__label"> Scientists and Research </span> </button> <div class="accordion__panel" id="acc-panel-scientists-and-research" data-accordion="panel" aria-labelledby="acc-button-scientists-and-research" role="region"> <div class="accordion accordion--secondary"> <button class="accordion__button" id="acc-button-scientific-research" data-accordion="button" aria-controls="acc-panel-scientific-research" aria-expanded="false"> <span class="accordion__button__label"> Scientific Research </span> </button> <div class="accordion__panel" id="acc-panel-scientific-research" data-accordion="panel" aria-labelledby="acc-button-scientific-research" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/scientists-and-research/58/collaborative-research-in-the-arctic-towards-understanding-climate-change/183">Collaborative Research in the Arctic Towards Understanding Climate Change</a></li> <li><a href="/en/library/scientists-and-research/58/from-stable-chromosomes-to-jumping-genes/184">From Stable Chromosomes to Jumping Genes</a></li> <li><a href="/en/library/scientists-and-research/58/an-elegant-experiment-to-test-the-process-of-dna-replication/187">An Elegant Experiment to Test the Process of DNA Replication</a></li> <li><a href="/en/library/scientists-and-research/58/the-founding-of-neuroscience/233">The Founding of Neuroscience</a></li> <li><a href="/en/library/scientists-and-research/58/tracking-endangered-jaguars-across-the-border/189">Tracking Endangered Jaguars across the Border</a></li> <li><a href="/en/library/scientists-and-research/58/atmospheric-chemistry-research-that-changed-global-policy/211">Atmospheric Chemistry Research that Changed Global Policy</a></li> <li><a href="/en/library/scientists-and-research/58/revolutionizing-medicine-with-monoclonal-antibodies/220">Revolutionizing Medicine with Monoclonal Antibodies</a></li> <li><a href="/en/library/scientists-and-research/58/uncovering-the-mysteries-of-chronic-mountain-sickness/238">Uncovering the Mysteries of Chronic Mountain Sickness</a></li> </ul> </div> <button class="accordion__button" id="acc-button-profiles-in-science" data-accordion="button" aria-controls="acc-panel-profiles-in-science" aria-expanded="false"> <span class="accordion__button__label"> Profiles in Science </span> </button> <div class="accordion__panel" id="acc-panel-profiles-in-science" data-accordion="panel" aria-labelledby="acc-button-profiles-in-science" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/scientists-and-research/58/luis-e.-miramontes/232">Luis E. Miramontes</a></li> <li><a href="/en/library/scientists-and-research/58/bernardo-houssay/237">Bernardo Houssay</a></li> <li><a href="/en/library/scientists-and-research/58/craig-lee/256">Craig Lee</a></li> <li><a href="/en/library/scientists-and-research/58/david-ho/241">David Ho</a></li> <li><a href="/en/library/scientists-and-research/58/louis-tompkins-wright/244">Louis Tompkins Wright</a></li> <li><a href="/en/library/scientists-and-research/58/carlos-j.-finlay/217">Carlos J. Finlay</a></li> <li><a href="/en/library/scientists-and-research/58/cecilia-payne/290">Cecilia Payne</a></li> <li><a href="/en/library/scientists-and-research/58/jazmin-scarlett/291">Jazmin Scarlett</a></li> <li><a href="/en/library/scientists-and-research/58/ramari-stewart/292">Ramari Stewart</a></li> <li><a href="/en/library/scientists-and-research/58/johnson-cerda/300">Johnson Cerda</a></li> <li><a href="/en/library/scientists-and-research/58/ellen-ochoa/201">Ellen Ochoa</a></li> <li><a href="/en/library/scientists-and-research/58/ruth-benerito/205">Ruth Benerito</a></li> <li><a href="/en/library/scientists-and-research/58/franklin-chang-díaz/219">Franklin Chang Díaz</a></li> <li><a href="/en/library/scientists-and-research/58/percy-lavon-julian/221">Percy Lavon Julian</a></li> <li><a href="/en/library/scientists-and-research/58/luis-walter-alvarez/229">Luis Walter Alvarez</a></li> <li><a href="/en/library/scientists-and-research/58/france-anne-dominic-córdova/230">France Anne-Dominic Córdova</a></li> </ul> </div> </div> </div> </div> </div> </li> <li>  <button class="button" data-toggle="dropdown">Biology </button> <div class="nav__dropdown box-shadow-1 padding-1"> <div class="accordion accordion--secondary font-size-sm"> <div class="accordion accordion--secondary"> <button class="accordion__button" id="acc-sub-button-biological-molecules" data-accordion="button" aria-controls="acc-sub-panel-biological-molecules" aria-expanded="false"> <span class="accordion__button__label"> Biological Molecules </span> </button> <div class="accordion__panel" id="acc-sub-panel-biological-molecules" data-accordion="panel" aria-labelledby="acc-sub-button-biological-molecules" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/biology/2/carbohydrates/61">Carbohydrates</a></li> <li><a href="/en/library/biology/2/fats-and-proteins/62">Fats and Proteins</a></li> <li><a href="/en/library/biology/2/biological-proteins/243">Biological Proteins</a></li> <li><a href="/en/library/biology/2/blood-biology-i/242">Blood Biology I</a></li> <li><a href="/en/library/biology/2/lipids/207">Lipids</a></li> </ul> </div> <button class="accordion__button" id="acc-sub-button-cell-biology" data-accordion="button" aria-controls="acc-sub-panel-cell-biology" aria-expanded="false"> <span class="accordion__button__label"> Cell Biology </span> </button> <div class="accordion__panel" id="acc-sub-panel-cell-biology" data-accordion="panel" aria-labelledby="acc-sub-button-cell-biology" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/biology/2/discovery-and-structure-of-cells/64">Discovery and Structure of Cells</a></li> <li><a href="/en/library/biology/2/respiration/285">Respiration</a></li> <li><a href="/en/library/biology/2/membranes-i/198">Membranes I</a></li> <li><a href="/en/library/biology/2/membranes-ii/204">Membranes II</a></li> <li><a href="/en/library/biology/2/cellular-organelles-i/195">Cellular Organelles I</a></li> <li><a href="/en/library/biology/2/cell-division-i/196">Cell Division I</a></li> <li><a href="/en/library/biology/2/cell-division-ii/212">Cell Division II</a></li> <li><a href="/en/library/biology/2/membranes-and-chemical-transport/106">Membranes and Chemical Transport</a></li> </ul> </div> <button class="accordion__button" id="acc-sub-button-energy-in-living-systems" data-accordion="button" aria-controls="acc-sub-panel-energy-in-living-systems" aria-expanded="false"> <span class="accordion__button__label"> Energy in Living Systems </span> </button> <div class="accordion__panel" id="acc-sub-panel-energy-in-living-systems" data-accordion="panel" aria-labelledby="acc-sub-button-energy-in-living-systems" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/biology/2/energy-metabolism-i/215">Energy Metabolism I</a></li> <li><a href="/en/library/biology/2/energy-metabolism-ii/225">Energy Metabolism II</a></li> <li><a href="/en/library/biology/2/photosynthesis-i/192">Photosynthesis I</a></li> </ul> </div> <button class="accordion__button" id="acc-sub-button-evolutionary-biology" data-accordion="button" aria-controls="acc-sub-panel-evolutionary-biology" aria-expanded="false"> <span class="accordion__button__label"> Evolutionary Biology </span> </button> <div class="accordion__panel" id="acc-sub-panel-evolutionary-biology" data-accordion="panel" aria-labelledby="acc-sub-button-evolutionary-biology" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/biology/2/origins-of-life-i/226">Origins of Life I</a></li> <li><a href="/en/library/biology/2/origins-of-life-ii/227">Origins of Life II</a></li> <li><a href="/en/library/biology/2/extinction/295">Extinction</a></li> <li><a href="/en/library/biology/2/mass-extinctions/294">Mass Extinctions</a></li> <li class="current">Charles Darwin I</li> <li><a href="/en/library/biology/2/charles-darwin-ii/111">Charles Darwin II</a></li> <li><a href="/en/library/biology/2/charles-darwin-iii/112">Charles Darwin III</a></li> <li><a href="/en/library/biology/2/adaptation/68">Adaptation</a></li> <li><a href="/en/library/biology/2/taxonomy-i/70">Taxonomy I</a></li> <li><a href="/en/library/biology/2/taxonomy-ii/89">Taxonomy II</a></li> <li><a href="/en/library/biology/2/introduction-to-paleoanthropology/258">Introduction to Paleoanthropology</a></li> <li><a href="/en/library/biology/2/the-piltdown-hoax/263">The Piltdown Hoax</a></li> <li><a href="/en/library/biology/2/future-of-human-evolution/259">Future of Human Evolution</a></li> </ul> </div> <button class="accordion__button" id="acc-sub-button-genetics" data-accordion="button" aria-controls="acc-sub-panel-genetics" aria-expanded="false"> <span class="accordion__button__label"> Genetics </span> </button> <div class="accordion__panel" id="acc-sub-panel-genetics" data-accordion="panel" aria-labelledby="acc-sub-button-genetics" role="region"> <ul class="nav text-color-link"> 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text-color-link"> <li><a href="/en/library/biology/2/biodiversity-i/276">Biodiversity I</a></li> <li><a href="/en/library/biology/2/ecosystem-services/279">Ecosystem Services</a></li> <li><a href="/en/library/biology/2/animal-ecology/283">Animal Ecology</a></li> <li><a href="/en/library/biology/2/biodiversity-ii/281">Biodiversity II</a></li> <li><a href="/en/library/biology/2/animal-behavior/286">Animal Behavior</a></li> <li><a href="/en/library/biology/2/population-biology/287">Population Biology</a></li> <li><a href="/en/library/biology/2/trophic-ecology/293">Trophic Ecology</a></li> </ul> </div> </div> </div> </div> </li> </ul> </nav>  <div id="theTop"></div> <main id="skip-header-content"> <div class="margin-bottom-5"> <article class="container wide module"> <header class="grid grid--sidebar-right module__header"> <div class="module__header__title"> <span class="subcategory"> <strong><em>Evolutionary Biology</em></strong> </span> <h1>Charles Darwin I: <sub><em>The Origin of Species</em></sub></h1> <p class="byline">by Alfred L. Rosenberger, Ph.D.</p> <nav class="module__header__tabs"> <ul class="tabs-nav tabs-nav--horizontal library"> <li> <a href="/en/library/biology/2/charles-darwin-i/110/reading" aria-current="page" >Reading</a> </li> <li> <a href="/en/library/biology/2/charles-darwin-i/110/quiz">Quiz</a> </li> <li> <a href="/en/library/biology/2/charles-darwin-i/110/resources">Teach with this</a> </li> </ul> </nav> </div> <script type="application/ld+json"> { "@context": "http://schema.org", "@type": "AudioObject", "contentUrl": "https://www.visionlearning.com/img/library/moduleAudio/module_110.mp3", "description": "Recording of Charles Darwin I : The experiences and observations of Charles Darwin significantly contributed to his theory of evolution through natural selection. This module explores those influences and describes evolution as a force for biological change and diversification. The first in a series, it details how the theory challenged the cultural mindset of the time, including the effect of his major works: <em>On the Origin of Species by Means of Natural Selection</em> and <em>Sexual Selection and the Descent of Man.</em>", "encodingFormat": "mp3", "name": "module_110.mp3" } </script> <div class="module_header_audio"> <div class="audio-player border border-radius"> <audio id="audio"> <source src="https://www.visionlearning.com/img/library/moduleAudio/module_110.mp3" type="audio/mpeg"> Your browser does not support the audio element. </audio> <div class="audio-player__title"> <p>Listen to this reading</p> <span class="audio-player__timestamp" id="timestamp"> 00:00 </span> </div> <div class="audio-player__controls" id="controls"> <button class="button button--icon-only" id="play-pause-button"> <span class="icon icon-play" aria-hidden="true"></span> </button> <div class="audio-player__progress" id="progress-bar" tabindex="0" aria-valuemin="0" aria-valuemax="100" aria-valuenow="0" aria-label="Use arrow keys to forward or rewind the audio" role="slider"> <div class="audio-player__progress__fill"> <span class="audio-player__thumb"></span> </div> </div> <div class="audio-player__volume-container"> <button id="mute-button"> <span class="icon icon-volume"></span> </button> <div class="audio-player__volume" tabindex="0" aria-valuemin="0" aria-valuemax="100" aria-valuenow="100" aria-label="Use arrow keys to adjust volume" role="slider"> <div class="audio-player__volume__fill"> <span class="audio-player__thumb"></span> </div> </div> </div> </div> </div> </div> </header> <hr class="divider"/>   <div class="grid grid--sidebar-right grid--divider"> <div class="order-2 order-1--lg module__main"> <div class="narrow margin-x-auto margin-y-5"> <div class="accordion margin-bottom-5">  <button class="accordion__button" id="acc-button-key-concepts" data-accordion="button" aria-controls="acc-panel-key-concepts" aria-expanded="true" tabindex="0"> Did you know? </button> <div class="accordion__panel shown show" id="acc-panel-key-concepts" data-accordion="panel" aria-labelledby="acc-button-key-concepts" role="region"> <div class="accordion__panel__content"> <p>Did you know that the theory of evolution did not begin with Charles Darwin? The idea of evolution was part of Western thought for more than 2,000 years before Darwin changed the world with his legendary book <em>On the Origin of Species. </em></p> </div> </div>  <button class="accordion__button" id="acc-button-table-of-contents" data-accordion="button" aria-controls="acc-panel-table-of-contents" aria-expanded="false" tabindex="0"> Key concepts </button> <div class="accordion__panel" id="acc-panel-table-of-contents" data-accordion="panel" aria-labelledby="acc-button-table-of-contents" role="region" aria-hidden="true"> <div class="accordion__panel__content"> <ul class="bulleted"><li><p>Charles Darwin played a key role in supporting and explaining the theory of evolution through natural selection.</p></li> <li><p>Darwin's skills of observation and ability to record data accurately allowed him to create a comprehensive model of the mechanism by which evolution occurs.</p></li> <li><p>The theory of evolution through natural selection explains how all forms of life are related to one another genealogically, and emphasizes that variation within a species is the root for evolutionary change.</p></li></ul> </div> </div>  <button class="accordion__button" id="acc-button-terms-you-should-know" data-accordion="button" aria-controls="acc-panel-terms-you-should-know" aria-expanded="false" tabindex="0"> Terms you should know </button> <div class="accordion__panel" id="acc-panel-terms-you-should-know" data-accordion="panel" aria-labelledby="acc-button-terms-you-should-know" role="region" aria-hidden="true"> <div class="accordion__panel__content"> <dl> <dt>origin </dt> <dd> source; starting point </dd> <dt><a href="/en/glossary/view/species">species </a></dt> <dd> a distinct variety of animal or plant that breed only among their own kind </dd> <dt>naturalist </dt> <dd> a person who studies the natural world</dd> </dl> </div> </div> </div> <hr class="border-color-dark" /> <section> <div class="container narrow"> <p>Few people have changed the world with the power of an idea. <mark class="term" data-term="Charles Darwin" data-term-def="English naturalist and geologist born in Shrewsbury, Shropshire (1809-1882). While serving as naturalist aboard HMS Beagle, Darwin developed his theory of&hellip;" data-term-url="/en/glossary/view/Darwin%2C+Charles/4507">Charles Darwin</mark>, the British naturalist who lived during the 1800s, was one of them. While we might equate the idea of <mark class="term" data-term="evolution" data-term-def="Change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift." data-term-url="/en/glossary/view/evolution/5284">evolution</mark> with other revolutionary scientific breakthroughs, such as Einstein's general <mark class="term" data-term="theory" data-term-def="A scientific theory is an explanation inferred from multiple lines of evidence for some broad aspect of the natural world and&hellip;" data-term-url="/en/glossary/view/theory/4854">theory</mark> of <mark class="term" data-term="relativity" data-term-def="In science, relativity usually refers to the general theory of relativity, formulated by Albert Einstein in 1915. Einstein's general theory of&hellip;" data-term-url="/en/glossary/view/relativity/5287">relativity</mark>, people seem to care less about what it means to live in a <mark class="term" data-term="universe" data-term-def="The cosmos and everything that exists in it." data-term-url="/en/glossary/view/universe/5288">universe</mark> where the speed of <mark class="term" data-term="light" data-term-def="A form of electromagnetic radiation. Visible light is that associated with stimulating the organs of sight, which for normal human&hellip;" data-term-url="/en/glossary/view/light/1498">light</mark> is fixed than in a world in which humans descended from hairy apes. </p> <p>That is a tricky question because of its implications about the very nature of life, humanity, and religion. It is the reason why some greet Darwin's name with a gut-level sense of distrust even though his contributions to our understanding of life are as solidly confirmed as are Einstein's contributions to our understanding of the <mark class="term" data-term="universe" data-term-def="The cosmos and everything that exists in it." data-term-url="/en/glossary/view/universe/5288">universe</mark>. So, it is no surprise that more people have an inkling – too often wrong – of what is meant by Darwin's concept of <mark class="term" data-term="natural selection" data-term-def="The process whereby characteristics that promote survival and reproduction are passed on to future generations, so these characteristics become more frequent&hellip;" data-term-url="/en/glossary/view/natural+selection/11402">natural selection</mark> than by the terms of Einstein's famous equation E = mc<sup>2</sup>.</p> <p><section id="toc_1" class=""> <h2><em>On the Origin of Species</em></h2></p> <p>Darwin's legendary book, <em>On the Origin of Species by Means of <mark class="term" data-term="natural selection" data-term-def="The process whereby characteristics that promote survival and reproduction are passed on to future generations, so these characteristics become more frequent&hellip;" data-term-url="/en/glossary/view/natural+selection/11402">Natural Selection</mark>; or, the Preservation of Favoured Races in the Struggle for Life</em>, is frequently listed as one of the greatest books ever written. The three critical ideas he developed in it are:</p><p><blockquote><p><ul class="bulleted"> <li>The fact that evolution occurs.</li> <li>The theory that natural selection is the driving force or mechanism behind the process of evolution.</li> <li>The concept of phylogeny, that all forms of life are related to one another genealogically, through their pedigree or "family's roots."</li> </ul></p></blockquote></p><p>Darwin began developing these ideas as a result of his experiences during a five-year voyage on the British survey vessel H.M.S. <em>Beagle</em>, which sailed around the world on a mapping expedition during the early 1830s (Figure 1). Darwin was on board to work as the ship's naturalist, to record information about the geology, sea life, land animals and plants, and people that the <em>Beagle</em> would discover. When he set sail in 1831, Darwin was twenty-two years old, fresh out of college, fascinated with science, and deeply interested in geology and <mark class="term" data-term="natural history" data-term-def="The sciences dealing with the study of all objects in nature; used more commonly in the 18th and 19th centuries to&hellip;" data-term-url="/en/glossary/view/natural+history/5271">natural history</mark>. He was planning to become a clergyman, partly because he thought it would allow him enough free time to pursue his other interests.</p> <div class="figure"> <figure> <button class="lightbox-button lightbox-button--icon" data-lightbox="" data-lightbox-src="/img/library/large_images/image_9023.jpg"> <img src="/img/library/modules/mid110/Image/VLObject-9023-151013031011.jpg" alt="Figure 1: The HMS Beagle, a 90.3 ft, 10 gun brig-sloop of the British Royal Navy. This file comes from Wellcome Images, a website operated by Wellcome Trust, a global charitable foundation based in the UK." /> </button> <figcaption> <p><strong>Figure 1</strong>: The HMS Beagle, a 90.3 ft, 10 gun brig-sloop of the British Royal Navy. This file comes from <a href="http://wellcomeimages.org/">Wellcome Images</a>, a website operated by Wellcome Trust, a global charitable foundation based in the UK.</p> <span class="credit">image ©Wellcome Images/CC-BY-4.0</span> </figcaption> </figure> </div> <div class="comprehension-checkpoint margin-y-4"> <h6 class="comprehension-checkpoint__header"> <span> <span class="icon icon-question"></span> </span> Comprehension Checkpoint </h6> <form class="" name="cc6104"> <div class="form-entry"> <div class="form-entry__field"> <span class="form-entry__field__label">One of the main ideas of Darwins' book <em>On the Origins of Species</em> was that all forms of life share family roots.</span> <div class="form-entry__option"> <div class="form-entry__option__radio" data-answer="correct"> <label> <input id="q1-6104-0-option-a" name="quiz-option-6104" type="radio" value="true" > <span class="option__label"> <span class="screen-reader-only">a.</span> true </span> </label> <span class="quiz__response" id="response-6104-0"> <strong>Correct!</strong> </span> </div> <div class="form-entry__option__radio" data-answer="incorrect"> <label> <input id="q1-6104-1-option-b" name="quiz-option-6104" type="radio" value="false" > <span class="option__label"> <span class="screen-reader-only">b.</span> false </span> </label> <span class="quiz__response" id="response-6104-1"> <strong>Incorrect.</strong> </span> </div> </div> </div> </div> </form> </div> </section> <section id="toc_2"> <h2>Ideas about evolution through history</h2><p>Darwin was keenly aware that the idea of <mark class="term" data-term="evolution" data-term-def="Change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift." data-term-url="/en/glossary/view/evolution/5284">evolution</mark> was in the air and was being hotly debated in some circles. Actually, it had been part of Western thought for more than 2,000 years, at least since the Greek philosopher <mark class="term" data-term="Aristotle" data-term-def="A Greek philosopher born in Stagira (384-322 BCE). He joined Plato's Academy in Athens (then being run by Eudoxus) at the&hellip;" data-term-url="/en/glossary/view/Aristotle/4466">Aristotle</mark> proposed there were natural <mark class="term" data-term="law" data-term-def="In science, a principle that describes a phenomenon, often mathematically." data-term-url="/en/glossary/view/law/8686">laws</mark> that explained how the world came to be. These laws were meant to be alternatives to the usual <mark class="term" data-term="myth" data-term-def="A story, idea, or concept invented with a purpose. Myths are generally intended to explain the relationship between gods or natural&hellip;" data-term-url="/en/glossary/view/myth/5285">myths</mark> and stories about the origins of the <mark class="term" data-term="universe" data-term-def="The cosmos and everything that exists in it." data-term-url="/en/glossary/view/universe/5288">universe</mark> and of people that all native cultures seem to generate. Some of Aristotle's proposals were quite specific. He believed, for example, that there were "higher" <mark class="term" data-term="species" data-term-def="1. In biological classifications, it is the lowest and most basic unit of the Linnaean taxonomic hierarchy (although it is also&hellip;" data-term-url="/en/glossary/view/species/893">species</mark> and also "lower" species, and the lower ones gave rise to the higher. </p><p>As Europe emerged from the <mark class="term" data-term="Middle Ages" data-term-def="European history from the 5th century to the 15th century. The Middle Ages follow the fall of the Western Roman Empire&hellip;" data-term-url="/en/glossary/view/Middle+Ages/5329">Middle Ages</mark>, scientists interested in biology considered <mark class="term" data-term="evolution" data-term-def="Change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift." data-term-url="/en/glossary/view/evolution/5284">evolution</mark> an idea of historical importance. One of Darwin's own grandfathers, Dr. Erasmus Darwin, had even written extensively about evolution. But what changed the <mark class="term" data-term="climate" data-term-def="Climate describes the average and patterns of a particular area’s weather over time. Climate includes such elements as temperature, precipitation, humidity,&hellip;" data-term-url="/en/glossary/view/climate/9334">climate</mark> of Darwin's times was that the natural sciences were becoming modernized and professionalized, with their own societies, meetings, and publications. This allowed the fuzzy notion of evolution to rise to the level of a scientific <mark class="term" data-term="hypothesis" data-term-def="From the Greek word <em>hypothesis</em> meaning assumption or the basis of an argument, a hypothesis is a proposal intended to explain&hellip;" data-term-url="/en/glossary/view/hypothesis/3727">hypothesis</mark>, which might be proven or disproven by <mark class="term" data-term="research" data-term-def="A study or an investigation." data-term-url="/en/glossary/view/research/8257">research</mark>, <mark class="term" data-term="evidence" data-term-def="Support for an idea, opinion, or hypothesis." data-term-url="/en/glossary/view/evidence/8243">evidence</mark>, and a <mark class="term" data-term="method" data-term-def="A procedure or process; a systematic way of performing a task or conducting research." data-term-url="/en/glossary/view/method/8238">method</mark> of reasoning.</p></section> <section id="toc_3"> <h2>Evolution vs. fixity</h2><p>As the mid-1800s approached, the idea of <mark class="term" data-term="evolution" data-term-def="Change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift." data-term-url="/en/glossary/view/evolution/5284">evolution</mark> posed a serious challenge to the then-popular view that <mark class="term" data-term="species" data-term-def="1. In biological classifications, it is the lowest and most basic unit of the Linnaean taxonomic hierarchy (although it is also&hellip;" data-term-url="/en/glossary/view/species/893">species</mark> were unchanging fixtures of nature. This concept, called the <mark class="term" data-term="Fixity of Species" data-term-def="An idea popular among 16th and 17th century European zoologists and botanists that reflected Western religion and the story of creation&hellip;" data-term-url="/en/glossary/view/Fixity+of+Species/4763">Fixity of Species</mark>, was a perspective that European zoologists and botanists adopted as part of their culture, to reflect Western religion and the story of creation as laid out in the Bible. A key feature of the scientific argument for "fixity" was the notion that the structure of each species was based on a <mark class="term" data-term="model" data-term-def="A representation, pattern, or mathematical description that can help scientists replicate a system." data-term-url="/en/glossary/view/model/8236">model</mark>, ideal form. In other words, botanists would make the case that all wild briar roses were supposed to look like replicas of one another because a wild briar rose was meant to be built in a precise, definite way or it would not be a wild briar rose. Why? Because each wild briar rose was a product of God's "perfect" acts of creation. And if each was meant to be perfect, there was no reason for any to change, and no possibility that they ever did.</p><p>The fixity idea, however, was not satisfactory to all. Some geologists and zoologists thought that <mark class="term" data-term="species" data-term-def="1. In biological classifications, it is the lowest and most basic unit of the Linnaean taxonomic hierarchy (although it is also&hellip;" data-term-url="/en/glossary/view/species/893">species</mark> might actually change over time. In fact, the possibility of <mark class="term" data-term="evolution" data-term-def="Change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift." data-term-url="/en/glossary/view/evolution/5284">evolution</mark> being a fundamental feature of nature eventually became the crucial question of nineteenth-century science. One of the reasons why this happened was that <mark class="term" data-term="fossil" data-term-def="The preserved impression or remains of an animal or plant whose living tissue has been replaced by minerals." data-term-url="/en/glossary/view/fossil/8558">fossils</mark> were slowly being discovered, some in highly "imperfect" <mark class="term" data-term="environment" data-term-def="The conditions that surround and affect an organism." data-term-url="/en/glossary/view/environment/8270">environments</mark> that seemed not to follow the logic of creation – such as the occurrence of ocean seashells found buried on the tops of mountains such as the Alps and the Himalayas.</p><p>Darwin allowed himself to wonder if <mark class="term" data-term="species" data-term-def="1. In biological classifications, it is the lowest and most basic unit of the Linnaean taxonomic hierarchy (although it is also&hellip;" data-term-url="/en/glossary/view/species/893">species</mark> were fixed or prone to <mark class="term" data-term="evolution" data-term-def="Change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift." data-term-url="/en/glossary/view/evolution/5284">evolution</mark>. With the intense experience of five years of living and working on the <em>Beagle</em>, collecting and describing a vast number and variety of <mark class="term" data-term="natural history" data-term-def="The sciences dealing with the study of all objects in nature; used more commonly in the 18th and 19th centuries to&hellip;" data-term-url="/en/glossary/view/natural+history/5271">natural history</mark> specimens, he developed into a first-rate naturalist – actually, the best in the world. He came to see species differently than those who saw perfection in them. Darwin did not focus on the sameness of individuals; rather, he thought it was important that individuals, like you and me, vary in spite of the fact that we belong to the same species. He realized that the variations could become the raw material for evolutionary change.</p> <div class="comprehension-checkpoint margin-y-4"> <h6 class="comprehension-checkpoint__header"> <span> <span class="icon icon-question"></span> </span> Comprehension Checkpoint </h6> <form class="" name="cc9026"> <div class="form-entry"> <div class="form-entry__field"> <span class="form-entry__field__label">In Darwin's day, most people believed that</span> <div class="form-entry__option"> <div class="form-entry__option__radio" data-answer="incorrect"> <label> <input id="q1-9026-0-option-a" name="quiz-option-9026" type="radio" value="plants and animals changed in structure over time as they adapt to their environment." > <span class="option__label"> <span class="screen-reader-only">a.</span> plants and animals changed in structure over time as they adapt to their environment. </span> </label> <span class="quiz__response" id="response-9026-0"> <strong>Incorrect.</strong> </span> </div> <div class="form-entry__option__radio" data-answer="correct"> <label> <input id="q1-9026-1-option-b" name="quiz-option-9026" type="radio" value="each species was based on a perfect model so there was no reason or possibility to change." > <span class="option__label"> <span class="screen-reader-only">b.</span> each species was based on a perfect model so there was no reason or possibility to change. </span> </label> <span class="quiz__response" id="response-9026-1"> <strong>Correct!</strong> </span> </div> </div> </div> </div> </form> </div> </section> <section id="toc_4"> <h2>Clues to evolution: Birds and fossils</h2><p>One of the clues that moved Darwin to totally accept the <mark class="term" data-term="principle" data-term-def="In the sciences, a principle is a fundamental, primary, or general law or truth. For instance, one of the most basic&hellip;" data-term-url="/en/glossary/view/principle/5289">principle</mark> of <mark class="term" data-term="evolution" data-term-def="Change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift." data-term-url="/en/glossary/view/evolution/5284">evolution</mark> involved a group of small birds called mockingbirds. Mockingbirds are unspectacular animals with a wingspan of about 10 inches. They live in many <mark class="term" data-term="habitat" data-term-def="The place or type of environment where a wild plant, animal, or other organism naturally lives or grows." data-term-url="/en/glossary/view/habitat/5593">habitats</mark> in North, Central, and South America, from southern Canada to Chile and Argentina. Darwin observed and collected them on the Galapagos, a cluster of small islands off the coast of Ecuador (Figure 2), and sent his specimens back to London for study. </p> <div class="figure"> <figure> <button class="lightbox-button lightbox-button--icon" data-lightbox="" data-lightbox-src="/img/library/large_images/image_2449.jpg"> <img src="/img/library/modules/mid110/Image/VLObject-2449-031121111113.jpg" alt="Figure 2: The Beagle's route through the Galapagos in 1835. Red triangles indicate volcanic peaks on the islands. Darwin's observations of differences between animals inhabiting the different islands in the archipelago was instrumental to his development of his theory of evolution. " /> </button> <figcaption> <p><strong>Figure 2:</strong> The Beagle's route through the Galapagos in 1835. Red triangles indicate volcanic peaks on the islands. Darwin's observations of differences between animals inhabiting the different islands in the archipelago was instrumental to his development of his theory of evolution. </p> <span class="credit">image ©Emory University</span> </figcaption> </figure> </div> <p>After the voyage, Darwin consulted one of the most experienced ornithologists (bird specialists) in England, John Gould, about their <mark class="term" data-term="taxonomy" data-term-def="The basis, procedures, and rules for naming and classifying organisms." data-term-url="/en/glossary/view/taxonomy/894">taxonomy</mark> (see our <a href="/en/library/Biology/2/Taxonomy-I/70">Taxonomy</a> module). Darwin was surprised to learn that he had misclassified some of the birds because it was difficult for him to tell the <mark class="term" data-term="species" data-term-def="1. In biological classifications, it is the lowest and most basic unit of the Linnaean taxonomic hierarchy (although it is also&hellip;" data-term-url="/en/glossary/view/species/893">species</mark> apart from the subspecies. The physical <mark class="term" data-term="trait" data-term-def="A specific characteristic that is genetically determined." data-term-url="/en/glossary/view/trait/8271">traits</mark> of mockingbird species and subspecies blended into one another. For Darwin, this meant that the guidelines he had been trained to use to identify and classify animal and plant species, based on the idea that each one ought to have an idealized "perfect" form – <mark class="term" data-term="Fixity of Species" data-term-def="An idea popular among 16th and 17th century European zoologists and botanists that reflected Western religion and the story of creation&hellip;" data-term-url="/en/glossary/view/Fixity+of+Species/4763">Fixity of Species</mark> – was an arbitrary rule created by taxonomists, nothing more than an untested assumption. It logically followed that if species were not designed to be a series of perfect individual replicates, then evolutionary change – or "transmutation" of one species into another – was a possibility. Darwin saw immediately that some of Gould's species could have come into existence if one subspecies changed a little bit more than usual, perhaps as it got isolated on a separate island.</p><p>A second clue that led Darwin to embrace <mark class="term" data-term="evolution" data-term-def="Change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift." data-term-url="/en/glossary/view/evolution/5284">evolution</mark> had to do with <mark class="term" data-term="fossil" data-term-def="The preserved impression or remains of an animal or plant whose living tissue has been replaced by minerals." data-term-url="/en/glossary/view/fossil/8558">fossils</mark>. Fossils are formed when an <mark class="term" data-term="organism" data-term-def="Any connected living system, such as an animal, plant, fungus, or bacterium. Organisms may be composed of a single cell or&hellip;" data-term-url="/en/glossary/view/organism/2171">organism</mark> dies and its remains become hardened by absorbing <mark class="term" data-term="mineral" data-term-def="A naturally formed, inorganic solid with a specific chemical composition and characteristic crystal structure. Examples of minerals include quartz (SiO<sub>2</sub>), salt&hellip;" data-term-url="/en/glossary/view/mineral/2978">minerals</mark> from the earth in which they were buried. Thus, fossils are direct <mark class="term" data-term="evidence" data-term-def="Support for an idea, opinion, or hypothesis." data-term-url="/en/glossary/view/evidence/8243">evidence</mark> of life in the past and have great importance when considering a time-dependent concept such as evolution. In Argentina, Darwin collected fossils of gigantic armor-plated beasts, megatheres (Figure 3), which were unlike anything else anywhere in the world – nearly. Only the tank-like armadillos, which Darwin had also seen in South America, bore any resemblance to them. Considering these <mark class="term" data-term="extinction" data-term-url="/en/glossary/view/extinction" data-term-def="The complete and permanent loss of all individuals of a species of organism.">extinct</mark> and living forms together, Darwin theorized that megatheres and armadillos might be related. He thought they might be part of a large group of South American mammals that had evolved body armor as a protective <mark class="term" data-term="adaptation" data-term-def="A change that allows an organism to function better in a particular environment." data-term-url="/en/glossary/view/adaptation/8284">adaptation</mark>. He speculated that an ancient "cousin" of the megatheres might have been the ancestor of the armadillo.</p> <div class="figure"> <figure> <button class="lightbox-button lightbox-button--icon" data-lightbox="" data-lightbox-src="/img/library/large_images/image_9022.jpg"> <img src="/img/library/modules/mid110/Image/VLObject-9022-151013031004.jpg" alt="Figure 3: A fossil of the now-extinct Megatherium americanum, or giant ground sloth, that inhabited what is now South America from about 23 million years ago until around 12,000 years ago." /> </button> <figcaption> <p><strong>Figure 3</strong>: A fossil of the now-extinct <em>Megatherium americanum</em>, or giant ground sloth, that inhabited what is now South America from about 23 million years ago until around 12,000 years ago.</p> <span class="credit">image ©LadyofHats</span> </figcaption> </figure> </div> <p>The Galapagos mockingbirds and the Argentine megatheres provided Darwin with two complementary views of <mark class="term" data-term="evolution" data-term-def="Change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift." data-term-url="/en/glossary/view/evolution/5284">evolution</mark>. One helped him picture biological change by comparing living animals. The other helped him see it by comparing an <mark class="term" data-term="extinction" data-term-url="/en/glossary/view/extinction" data-term-def="The complete and permanent loss of all individuals of a species of organism.">extinct</mark> <mark class="term" data-term="species" data-term-def="1. In biological classifications, it is the lowest and most basic unit of the Linnaean taxonomic hierarchy (although it is also&hellip;" data-term-url="/en/glossary/view/species/893">species</mark> with one that was living. Darwin collected pieces of the evolutionary puzzle during his five years of sailing on the <i>Beagle</i>, but to solve the puzzle by putting the pieces together into a basic <mark class="term" data-term="model" data-term-def="A representation, pattern, or mathematical description that can help scientists replicate a system." data-term-url="/en/glossary/view/model/8236">model</mark> for the public to see would take him several more decades of effort. His work was capped by publication of <i>Origins</i> in 1859, more than twenty years after he began his voyage on the <i>Beagle</i>.</p></section> <section id="toc_5"> <h2>Response to <em>Origins</em></h2><p><em>Origins</em> was immediately recognized as a major scientific success. In one of the quirkiest episodes in the history of science, this happened to be the second time that Darwin published his explanation of <mark class="term" data-term="evolution" data-term-def="Change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift." data-term-url="/en/glossary/view/evolution/5284">evolution</mark>. A year earlier, Darwin learned that another naturalist, Alfred Russell Wallace, had also thought of evolution by <mark class="term" data-term="natural selection" data-term-def="The process whereby characteristics that promote survival and reproduction are passed on to future generations, so these characteristics become more frequent&hellip;" data-term-url="/en/glossary/view/natural+selection/11402">natural selection</mark>, and they eventually wrote a joint paper on the subject in order to share the credit. But the Darwin-Wallace essay did not compare with <em>Origins</em>, which included examples and reasoning that Darwin developed over a twenty-year period. <em>Origins</em> was much more than a statement on the controversial idea of evolution; it laid out a new <mark class="term" data-term="system" data-term-def="A group of interacting, interrelated or interdependent components that form a complex whole. The size of the system is defined for&hellip;" data-term-url="/en/glossary/view/system/3904">system</mark> of thought, another way of asking scientific questions, assembling scientific <mark class="term" data-term="evidence" data-term-def="Support for an idea, opinion, or hypothesis." data-term-url="/en/glossary/view/evidence/8243">evidence</mark>, and scientifically testing <mark class="term" data-term="hypothesis" data-term-url="/en/glossary/view/hypothesis" data-term-def="From the Greek word <em>hypothesis</em> meaning assumption or the basis of an argument, a hypothesis is a proposal intended to explain&hellip;">hypotheses</mark>.</p><p>Some people were less than happy with the book's publication. Since its central idea was that <mark class="term" data-term="evolution" data-term-def="Change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift." data-term-url="/en/glossary/view/evolution/5284">evolution</mark> is an ever-present, unstoppable, fundamental <mark class="term" data-term="law" data-term-def="In science, a principle that describes a phenomenon, often mathematically." data-term-url="/en/glossary/view/law/8686">law</mark> of nature, <em>Origins</em> became an angry flashpoint for those who cared less about the biological history of animals and plants than they cared about the deeper implications of the really big idea it represented – that in the middle 1800s there were new, logically sound, evidence-based ways of looking at life that challenged the religious ways of thinking that had been broadly accepted for centuries. (See Figure 4 for a parody of his <mark class="term" data-term="theory" data-term-def="A scientific theory is an explanation inferred from multiple lines of evidence for some broad aspect of the natural world and&hellip;" data-term-url="/en/glossary/view/theory/4854">theory</mark> of evolution.)</p> <div class="figure"> <figure> <button class="lightbox-button lightbox-button--icon" data-lightbox="" data-lightbox-src="/img/library/large_images/image_9029.jpg"> <img src="/img/library/modules/mid110/Image/VLObject-9029-151013031047.jpg" alt="Figure 4: Darwin's theories received some strongly negative reactions when they were published. Here Punch's Almanack, a satirical publication, satirizes Darwin's theory of evolution." /> </button> <figcaption> <p><strong>Figure 4</strong>: Darwin's theories received some strongly negative reactions when they were published. Here <em>Punch's Almanack</em>, a satirical publication, satirizes Darwin's theory of evolution.</p> <span class="credit">image ©Punch's Almanack</span> </figcaption> </figure> </div> <p>This makes it all the more interesting that the "Question of Questions" was not at all touched on in <em>Origins</em>. Darwin knew all along that this new science of evolutionary biology could be applied to human beings precisely the way he had applied it to mockingbirds and armadillos. Like the mockingbirds, people vary in appearance across countries and continents, and from one island to another. Like the armadillos and megatheres, the skeletons of modern humans closely resemble <mark class="term" data-term="extinction" data-term-url="/en/glossary/view/extinction" data-term-def="The complete and permanent loss of all individuals of a species of organism.">extinct</mark> <mark class="term" data-term="fossil" data-term-def="The preserved impression or remains of an animal or plant whose living tissue has been replaced by minerals." data-term-url="/en/glossary/view/fossil/8558">fossils</mark> then being discovered in the Neander Valley of Germany, fossils that would come to be known as <mark class="term" data-term="Neanderthal" data-term-def="An extinct species of humans, <em>Homo neanderthalensis</em>, who lived from approximately 400,000 to 40,000 years ago" data-term-url="/en/glossary/view/Neanderthal/11407">Neanderthal</mark> man. Darwin said nothing about this in <em>Origins</em> for, in his extraordinary thoroughness, he wasn't ready yet. He was also unprepared for the difficult personal battle that would have resulted if he had.</p> <div class="comprehension-checkpoint margin-y-4"> <h6 class="comprehension-checkpoint__header"> <span> <span class="icon icon-question"></span> </span> Comprehension Checkpoint </h6> <form class="" name="cc6112"> <div class="form-entry"> <div class="form-entry__field"> <span class="form-entry__field__label">When Darwin's book <em>On the Origin of Species</em> was published,</span> <div class="form-entry__option"> <div class="form-entry__option__radio" data-answer="incorrect"> <label> <input id="q1-6112-0-option-a" name="quiz-option-6112" type="radio" value="it was immediately accepted, by scientists and non-scientists alike, as scientific fact." > <span class="option__label"> <span class="screen-reader-only">a.</span> it was immediately accepted, by scientists and non-scientists alike, as scientific fact. </span> </label> <span class="quiz__response" id="response-6112-0"> <strong>Incorrect.</strong> </span> </div> <div class="form-entry__option__radio" data-answer="correct"> <label> <input id="q1-6112-1-option-b" name="quiz-option-6112" type="radio" value="it made some people angry because the idea of evolution challenged the religious thinking of the day." > <span class="option__label"> <span class="screen-reader-only">b.</span> it made some people angry because the idea of evolution challenged the religious thinking of the day. </span> </label> <span class="quiz__response" id="response-6112-1"> <strong>Correct!</strong> </span> </div> </div> </div> </div> </form> </div> </section> <section id="toc_6"> <h2>Human evolution: <em>Descent of Man</em></h2><p>About twelve years later, in 1871, Darwin did publish a book specifically about human <mark class="term" data-term="evolution" data-term-def="Change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift." data-term-url="/en/glossary/view/evolution/5284">evolution</mark>, <em>Sexual Selection and the <mark class="term" data-term="descent" data-term-def="Ancestry or heritage." data-term-url="/en/glossary/view/descent/8285">Descent</mark> of Man</em>. By then, the fury against his ideas had died down in England, and evolution was not a hotly contested issue any longer. By then, other highly accomplished scientists had written about people evolving, most notably <mark class="term" data-term="Thomas Henry Huxley" data-term-def="English biologist born in Ealing, Middlesex (1825-1895). While serving in the Navy as an assistant surgeon, Huxley collected and studied marine&hellip;" data-term-url="/en/glossary/view/Huxley%2C+Thomas+Henry/4553">Thomas Henry Huxley</mark>, in <em>Evidence as to Man's Place in Nature</em>, which appeared in 1863. The idea was slowly being absorbed by society. But nothing could match Darwin's brilliant thinking about the evolutionary <mark class="term" data-term="process" data-term-def="Method, procedure; series of actions or steps." data-term-url="/en/glossary/view/process/8256">process</mark>, so no one could match what Darwin would have to say about the subject of man. </p><p><em>Descent of Man</em> was as much about bringing out the few facts then known about human <mark class="term" data-term="evolution" data-term-def="Change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift." data-term-url="/en/glossary/view/evolution/5284">evolution</mark> as it was about the meaning of evolution as a way of thinking about our ethics and personal values. Darwin knew that evolution was one of the most important ideas for the human <mark class="term" data-term="species" data-term-def="1. In biological classifications, it is the lowest and most basic unit of the Linnaean taxonomic hierarchy (although it is also&hellip;" data-term-url="/en/glossary/view/species/893">species</mark> to comprehend. He knew that seeing us from an evolutionary perspective was more than peering through a telescope to look back at our own primitive origins. Evolution was also a mirror and a microscope for looking at ourselves as we are today.</p> </div> </section> <hr class="border-color-dark" /> <footer class="module__footer"> <p class="citation"> <em> Alfred L. Rosenberger, Ph.D. “Charles Darwin I” Visionlearning Vol. BIO (3), 2003. </em> </p>  <div class="title-list" name="further"> <p class="h6 title-list__title"> Further Reading </p> <ul class="grid grid--column-2--md grid--column-3--md gap-1"> <li> <a class="no-hover-focus height-100" href="/en/library/Biology/2/Charles-Darwin-II/111"> <article class="flex-row align-items-center flex-column--md align-items-start--md height-100 theme-light padding-2 gap-2"> <div class="width-30 width-auto--md"> <img class="border-radius box-shadow-1" src="/img/library/moduleImages/featured_image_111-23061209063155.jpg" alt="Charles Darwin II"> </div> <div class="flex-grow-shrink"> <h2 class="h6 font-weight-normal"> Charles Darwin II: <em>Natural selection</em> </h2> </div> </article> </a> </li> <li> <a class="no-hover-focus height-100" href="/en/library/Biology/2/Charles-Darwin-III/112"> <article class="flex-row align-items-center flex-column--md align-items-start--md height-100 theme-light padding-2 gap-2"> <div class="width-30 width-auto--md"> <img class="border-radius box-shadow-1" src="/img/library/moduleImages/featured_image_112-23061209063207.jpg" alt="Charles Darwin III"> </div> <div class="flex-grow-shrink"> <h2 class="h6 font-weight-normal"> Charles Darwin III: <em>Descent with modification</em> </h2> </div> </article> </a> </li> <li> <a class="no-hover-focus height-100" href="/en/library/Biology/2/Adaptation/68"> <article class="flex-row align-items-center flex-column--md align-items-start--md height-100 theme-light padding-2 gap-2"> <div class="width-30 width-auto--md"> <img class="border-radius box-shadow-1" src="/img/library/moduleImages/featured_image_68-23061209063221.jpeg" alt="Adaptation"> </div> <div class="flex-grow-shrink"> <h2 class="h6 font-weight-normal"> Adaptation: <em>The case of penguins</em> </h2> </div> </article> </a> </li> </ul> </div> </footer> </div>   </div>  <div class="order-1 order-2--lg module__tools"> <div class="narrow margin-x-auto position-sticky-top font-size-md"> <div class="padding-2 border-radius box-shadow-1--lg"> <div class="tabs" role="tablist"> <nav> <button class="button button--icon-label" id="tab-button-in-this-module" aria-label="Table of Contents" aria-controls="tab-panel-module__tools" aria-selected="true" role="tab"> <span class="icon icon-list" aria-hidden="true"></span> <span class="button__text">Contents</span> </button> <button class="button button--icon-label" id="tab-button-toggle-terms" aria-controls="tab-panel-toggle-terms" aria-selected="false" role="tab"> <span class="icon icon-glossary-highlight"></span> <span class="button__text">Glossary Terms</span> </button> </nav> <hr class="divider" /> <div class="tabs__panel shown" id="tab-panel-module__tools" aria-labelledby="tab-button-module__tools" role="tabpanel"> <p class="font-weight-bold margin-bottom-1"> Table of Contents </p> <div class="table-of-contents" id="module-toc"> <ul> <li><a href="/en/library/biology/2/charles-darwin-i/110#toc_1">On the Origin of Species</a> </li> <li><a href="/en/library/biology/2/charles-darwin-i/110#toc_2">Ideas about evolution through history</a> </li> <li><a href="/en/library/biology/2/charles-darwin-i/110#toc_3">Evolution vs. fixity</a> </li> <li><a href="/en/library/biology/2/charles-darwin-i/110#toc_4">Clues to evolution: Birds and fossils</a> </li> <li><a href="/en/library/biology/2/charles-darwin-i/110#toc_5">Response to Origins</a> </li> <li><a href="/en/library/biology/2/charles-darwin-i/110#toc_6">Human evolution: Descent of Man</a> </li> </ul> </div> </div>   <div class="tabs__panel" id="tab-panel-toggle-terms" aria-labelledby="tab-button-toggle-terms" role="tabpanel"> <div class="reading-toggle"> <div class="reading-toggle__switch"> <div class="form-entry__option__switch"> <label> <input type="checkbox" name="termsToggleSwitch" id="terms-toggle-switch" /> <span class="switch__slider"></span> <span class="option__label text-decoration-none font-size-md"> Highlight Glossary Terms </span> </label> </div> </div> <div class="reading-toggle__help"> <p> <em> Activate glossary term highlighting to easily identify key terms within the module. Once highlighted, you can click on these terms to view their definitions. </em> </p> </div> </div> </div> <div class="tabs__panel" id="tab-panel-toggle-ngss" aria-labelledby="tab-button-toggle-ngss" role="tabpanel"> <div class="reading-toggle"> <div class="reading-toggle__switch"> <div class="form-entry__option__switch"> <label> <input type="checkbox" name="ngssToggleSwitch" id="ngss-toggle-switch" /> <span class="switch__slider"></span> <span class="option__label text-decoration-none font-size-md"> Show NGSS Annotations </span> </label> </div> </div> <div class="reading-toggle__help"> <p> <em> Activate NGSS annotations to easily identify NGSS standards within the module. 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