Earth Day: Lost to History animals extinction extinctions Earth Day Quizzes Earth Day Colonization & Settlement, 1585-1763 Revolution & New Nation, 1754-1820s Expansion & Reform, 1801-1861 Civil War & Reconstruction, 1850-1877 Devel. of the Industrial US, 1870-1900 Emergence of Modern US, 1890-1930 Great Depression & WWII, 1929-1945 Postwar US, 1945-Early 1970s Contemporary US, 1968-Present Environment Read more about Earth Day: Lost to History Earth Day: Lost to History PDF Quiz