Read the full story for a discussion about what recent ecological reconstructions based on fossil pollen, charcoal and dung fungus spores tell us about the end of the Ice Age in interior North America.

Undisturbed archaeological sediments and remains include invisible chemical and physical clues to the past. Scientists studying ice cores from Antarctica and Greenland have analyzed the oxygen isotopes in small air bubbles contained in ice cores from ice that was formed thousands of years ago. They have found that the Earth underwent abrupt climate change between 14,700 and 14,500 years ago.

Period Time Subsistence Pattern Settlement Pattern Diagnostic Features Post war, global economy, information age AD 1945 to Present Corporate agriculture, international trade, service industry, and civil service Suburban-urbanization, second homes, rural abandonment Public works, transistors, interstate highways, disposable products, railroad abandonment, Teflon, computers Depression, recovery and war AD 1929 to AD 1945 Manufacturing, farming, retailing, [...]