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Lewis and Clark: Natural History Discoveries

In 1804, Meriwether Lewis and William Clark began their historic 8,000-mile exploration of the lands comprising the Louisiana Purchase. This guide lists books, articles and online resources useful for researching their many natural history discoveries.


Frederic Remington, artist. Lewis and Clark at the mouth of the Columbia River. 1905. Library of Congress Prints and Photographs Division.

In 1804, President Thomas Jefferson commissioned Meriwether Lewis to explore lands west of the Mississippi River that comprised the Louisiana Purchase. Lewis chose William Clark as his co-leader for the exploration. During the course of over two years they confronted harsh weather, unforgiving terrain, treacherous waters, injuries, starvation, disease and both friendly and hostile Native Americans. Nevertheless, the approximately 8,000-mile journey was a huge success and provided new geographic, ecological and social information about the unexplored areas of North America.

During their exploration Lewis and Clark identified 178 plants and 122 animals not previously known to science. This included discovering or carefully describing for the first time at least seven Great Plains mammals, including the pronghorn, grizzly bear, swift fox, black-tailed prairie dog, white-tailed jackrabbit, bushy-tailed woodrat, and mule deer.

William Clark, cartographer. Plan of the N.W. frontier. [1813?]. Library of Congress Geography and Map Division.

About the Science Section

Part of the Science & Business Reading Room at the Library of Congress, the Science Section is the starting point for conducting research at the Library of Congress in the subject areas of science, medicine and engineering. Here, reference specialists in specific subject areas of science and engineering  assist patrons in formulating search strategies and gaining access to the information and materials contained in the Library's rich collections of science, medicine, and engineering materials.