early american natural history

American Identity


Jefferson and the Mastodon: Observation over Theory


In Philadelphia at Peale’s American Museum, Charles Willson Peale housed a number of specimens which the growing republic’s natural historians consulted in their work.  In the early 1800s, 1 Peale was preparing to exhibit the first intact prehistoric mastodon skeleton.  The museum was known for its wide selection of animal and bird specimens as well as drawings, engravings, and books documenting the natural world.  Charles Willson Peale was passionate about America (he is best known today for his portraits of founding fathers) and about natural history; an American natural history museum was a natural choice for Peale to pursue.


As natural history was considered a key part of the development of the new America, Peale displayed his collections of New World specimens underneath portraits of American presidents and other early American leaders.


Peale’s mastodon is likely the first prehistoric skeleton to be assembled upright, and Peale displayed it in his Philadelphia museum, having images of it engraved for report and publication in scientific journals in America and Europe.  Peale himself commemorated the excavation of the mastodon (unearthed in New York in 1801).


Peale’s mastodon (or mammoth as it was called at the time) became a key piece of evidence in crucial scientific debates of the late 18th and early 19th century.   And one of these debates became a source of national pride for the young United States.


Peale’s mastodon (or mammoth as it was called at the time) became a key piece of evidence in crucial scientific debates of the late 18th and early 19th century.   And one of these debates became a source of national pride for the young United States.


First, however, this story must begin earlier in the first years of the American Republic.  A French scientist, Georges-Louis Leclerc, Comte de Buffon (1707 - 1788) proposed a theory, the heart of which would develop into biogeography.  He noted that even in parts of the globe where the climate and environment were similar, the animal species found in each region differed, being distinct to that region.  This came to be known as Buffon’s law.  He further argued that these different species came about from the migration of a few original species which were created at a central point.  He hypothesized that as the species migrated away from the point of creation, they could either improve or degenerate.  New World species Buffon declared to have degenerated. 2  He asserted the species of the New World were smaller, lesser version of European species.  His theories were so taken to heart in the larger intellectual climate that Europeans were warned that moving to the Americas would cause their children to degenerate from the effects of the climate. 3


New World scientists and statesmen were eager to prove Buffon wrong on the degeneracy of New World species. For a delightful discussion of Jefferson’s attempts to have an American moose sent to him in France in order to prove Buffon wrong, see Robert Krulwich's discussion of Jefferson's attempts to procure a Moose to send to Buffon.


The discovery of mastodon skeletons in America went a long way towards removing the prejudice against New World species. In 1785, Jefferson wrote a rebuttal to Buffon in his Notes of the State of Virginia, a report on the land, animals, plants, and Native Americans in that state.  After a consideration of the weights and sizes of Animals common to both Europe and North America, he concludes Buffon must be wrong.  And the mastodon is part of his argument: “The white bear of America is as large as that of Europe. The bones of the Mammoth which have been found in America, are as large as those found in the old world.” 4   Similarly, Jefferson defended the development of the Native Americans of Virginia as residing “not in a difference of nature, but of circumstance.” 5   In sending Lewis and Clark to explore the Louisiana territory, Jefferson was clear in instructing them to look for and collect mammoth (now mastodon) skeletons on their journey in the interests of supporting theories of the American environment as equal to that of the Old World.


Refuting the theories of Europeans about the local flora and fauna set up a trend in America towards favoring observation in the field over theory and even experimentation. In this case, Buffon retracted his theories on American animals as degenerate, and Jefferson and American natural historians were vindicated.  Yet this predilection to favor field observations over experiment or theory also lead to less accurate theories thriving in America, such as Swallow Submersion: the theory that swallows hibernated under water. 6



1. Ann Shelby Blum,  Picturing Nature American Nineteenth Century Zoological Illustration,  Princeton, N.J. : Princeton University Press, 1993), 19.

2. Ibid. and  "An American Behemoth: Peale's Mastodon," Treasures of the APS,  American Philosophical Society, last modified 2006, http://www.amphilsoc.org/exhibits/treasures/mastodon.htm .

3. Robert Krulwich, "Thomas Jefferson Needs A Dead Moose Right Now To Defend America," Krulwich Wonders, NPR, last modified January 16, 2014, http://www.npr.org/blogs/krulwich/2014/01/15/262916045/thomas-jefferson-needs-a-dead-moose-right-now-to-defend-america .

4. Thomas Jefferson,   “'Productions mineral, vegetable and animal’ A notice of the mines and other subterraneous riches; its trees, plants, fruits, &c.”, Notes on on the State of Virginia, 1785,  Electronic Text Center, University of Virginia Library,  ND, 176.

5. Ibid., 186.

6. Andrew J. Lewis, "A Democracy of Facts, an Empire of Reason: Swallow Submersion and Natural History in the Early American Republic,"  The William and Mary Quarterly, 62 no. 4 (Oct. 2005): 663-696, http://www.jstor.org/stable/3491444.


Arkansas Frameworks

Strand: Early United States

Content Standard 1: Students shall examine the causes and effects of migration patterns in the early history of North America.

(EUS.1.AH.1 )Evaluate the motivations for the exploration of the New World


This site  was created through a fellowship from the William Reese Company

and completed through the  Crystal Bridges Museum of American Art Library