Origin Story: A Big History of Everything

by David Christian

The largest and oldest world zone was Afro-Eurasia. This is where humans had evolved, and because there was a land bridge between Africa and Eurasia, ideas, people, and goods could move in relays over vast distances. The next-oldest world zone was Australia, first settled about sixty thousand years ago. The Australasian world zone was connected to Papua New Guinea and Tasmania during the last ice age but had the most tenuous of connections to Eurasia. The third-largest world zone, in the Americas, was settled at least by fifteen thousand years ago but was largely cut off from Eurasia when the Bering Strait was flooded at the end of the last ice age. In recent millennia, a fourth zone would emerge in the Pacific. Western islands such as the Solomons may have been settled as early as forty thousand years ago, but islands farther to the east and south (including New Zealand, Hawaii, and Easter Island) were settled during a remarkable series of seaborne migrations that began just thirty-five hundred years ago.