FIRST ERA
HUMANS ON EARTH
NORTH AMERICA NEAR EQUATOR
THIRD ERA
UNINHABITABLE
LONGEST ERA
APPALACHIAN MOUNTAINS FORMED
CANADIAN SHIELD
LAST ICE AGE
ROCKY AND INNUITIAN MOUNTAINS FORMED
PANGAEA BROKE APART
GLACIERS CARVED LAKES
DINOSAURS
PANGAEA FORMED
CURRENT ERA
SECOND ERA
