CLOVIS BACK to Ancient Cultures The Younger Dryas Trigger by Hermann Trappman. Did an impact trigger the Younger Dryas? A recent hypotheses suggests that one or more extraterrestrial bodies,  known as the Clovis Comet, broke up over North America about 12.9 to 11.6 thousand years ago, causing abrupt climatic cooling. Some scientists have proposed this triggered by catastrophic discharge of freshwater into … Continue reading Culture Shock