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| 1826–40 |
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| Johannes Müller (1801–58) developed his doctrine of specific nerve energies. He taught some of the most productive men in German physiology. | 1 |
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| 1828 |
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| Friedrich Wöhler (1800–82) announced the synthesis of urea, a typical product of animal metabolism. Urea synthesis and subsequent advances in organic synthesis crippled the vitalistic notion that a special force controls life processes. | 2 |
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| 1828 |
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| Karl von Baer (1792–1876) founded modern comparative embryology with the publication of Über Entwickelungsgeschichte der Thiere. Here he proclaimed that embryonic development is the history of increasing specificity. | 3 |
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| 1830–33 |
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| Charles Lyell (1797–1875) published his Principles of Geology, a powerful synthesis expounding and extending Hutton's uniformitarian theory. | 4 |
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| 1831–36 |
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| Charles Darwin (1809–82), as naturalist aboard HMS Beagle, studied South American flora and fauna, and gathered information he was later to use in his theory of evolution. | 5 |
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| c. 1831–52 |
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| Roderick Murchison (1792–1871) and Adam Sedgwick (1785–1873) described the succession of Paleozoic strata in Wales, Murchison defining the Silurian system (1839) and Sedgwick defining the Cambrian system. | 6 |
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| 1838–42 |
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| The United States Exploring Expedition, under the command of Lieut. Charles Wilkes (1798–1877), explored the Pacific Ocean, the first example of a U.S. government–sponsored scientific maritime venture. | 7 |
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| 1839 |
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| Theodor Schwann (1810–82) extended the 1838 observations on plant cells of Matthias Schleiden (1804–81) into the generalization that cells are the common structural and functional unit of all living organisms. | 8 |
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| 1840 |
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| Louis Agassiz (1807–73) elucidated the role of glaciers in geological change and enunciated his ice age theory. | 9 |
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| 1841 |
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| Carlo Matteucci (1811–68) demonstrated that a difference of electropotential exists between an excised nerve and damaged muscle. This stimulated Emil du Bois-Reymond (1818–96) to work in electrophysiology and to champion the German school of physiologists who wished to reduce physiological phenomena to physical and chemical processes. | 10 |
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| 1842 |
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| Liebig published Die Thierchemie, which promoted the analysis of organic compounds and described all physical and mental actions of animals as the result of chemical reactions. | 11 |
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| 1846 |
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| William T. G. Morton (1819–68) gave the first public demonstration of the use of ether as an anesthetic in surgery. | 12 |
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