7,300 Years Ago, One of Earth's Worst Eruptions Hit Japan. What Humans Did Next Surprised Scientists.

The Kikai-Akahoya volcanic eruption is one of the most destructive in history: Around 5250 BCE, almost 7,300 years ago, off the southwestern coast of Japan, it spewed massive amounts of magma and volcanic material from beneath the seabed in a series of blasts.