This week (Saturday the 23rd) marks the 200th anniversary of the return of the Lewis & Clark expedition. Earlier in the month the Corps of Discovery passed several traders' pirogues heading up the Missouri River, but on September 20th, 1806 -- two centuries ago today -- they encountered their first definite sign of European settlement in two years: cattle. "We saw some cows on the bank," William Clark reported, "which was a joyful sight to the party and caused a shout to be raised for joy." (William Bakeless, The Journals of Lewis and Clark, 382.)
It may seem a comical episode, but it also helps affirm Alfred Crosby's observation that the most important feature of early modern European expansion was the "portmanteau biota" Europeans brought with them: cattle, sheep, horses, swine, rabbits, wheat, grapes, peaches, various weed species, and epidemic diseases like smallpox. These plants, animals, and microbes provided European colonists with larger and more reliable supplies of food, fiber, and animal energy than their indigenous competitors, not to mention a biological arsenal (however inadvertantly used) that was far more lethal than Europeans' muskets and artillery. William Clark didn't mention all this in his journal entry, of course, but he did suggest that the most characteristic sound of Euro-American civilization in 1806 was not the pealing of church bells or the clanking of steam engines, but rather the mooing of American settlers' bovine vanguard.