Four species of elephants lived in North America until the end of the last ice age. Mammoths roamed the forests of Tennessee twelve to thirteen thousand years ago. Today, not a single proboscidean remains on this continent. Over a hundred species of megafauna went extinct during that same narrow window. The question is not whether something catastrophic happened, but what exactly caused such a sweeping die-off. The fossil record shows a clear before and after. These were not isolated extinctions scattered across millennia. They cluster around a specific moment in time. When you look at the scale and the suddenness, it becomes clear that normal climate variability does not explain what we see in the evidence.