In the years after the Revolutionary War, the fledgling republic of America was viewed by many Europeans as a degenerate backwater, populated by subspecies weak and feeble. Chief among these naysayers was the French Count and world-renowned naturalist Georges-Louis Leclerc de Buffon, who wrote that the flora and fauna of America (humans included) were inferior to European specimens. Thomas Jefferson--author of the Declaration of Independence, U.S...