Taxonomy term


Geologic Column: Lighting out for the territory

The author contemplates the history of westward expansion into arid lands and wonders if our unwise use of resources in places like the U.S. Southwest will eventually return the land "to the process of geology."

27 Feb 2015

Out of Africa, time and again

There is widespread agreement among scientists based on fossil and geochemical evidence that modern humans evolved in Africa between 200,000 and 100,000 years ago before spreading around the world. But the timing and route of this dispersal, and whether it occurred as a single exodus or in multiple pulses, remain contested. Now, a new study throws its weight behind a multiple-dispersal hypothesis, suggesting a first group of modern humans left Africa as early as 130,000 years ago, followed by a second about 80,000 years later.

27 Sep 2014

Fieldwork revises ice-free corridor hypothesis of human migration

The existence of an ice-free corridor through Canada during  the climax of last glaciation, which allowed the first Americans to cross the Bering land bridge from Siberia and move south (about 13,000 years ago), has long been postulated in North American archaeology. Now, research based on the exposure ages of glacial rocks found in the corridor suggests a puzzling conclusion — that the open pathway closed several thousand years prior to 20,000 years ago and didn’t open again until between 13,000 and 12,000 years ago, well after  first Americans were in the Americas.

13 Apr 2014

July 28, 1996: Kennewick man is discovered

On the evening of July 28, 1996, archaeologist James Chatters received an unexpected call at his home in Richland, Wash., from the local coroner. Two spectators at the local hydroplane races had found a skull in Columbia Park on the banks of the Columbia River near Kennewick, Wash. The coroner wanted Chatters, a paleontologist and forensic anthropologist affiliated with Central Washington University who often consulted for Benton County, to look at the skull and determine if it belonged to a recent murder victim. When the coroner arrived with the skull in a 5-gallon bucket, Chatters had scant notion that the discovery would end up challenging the reigning theory of the origins of the first Americans and would embroil scientists in a protracted, precedent-setting legal battle against the federal government.

27 Jul 2013

Modern humans arrived in South Asia 25,000 years later than previously thought?

Figuring out when modern humans left Africa and migrated throughout the world is a complicated task. For example, some evidence suggests modern humans may have migrated out of Africa and into Asia as early as 120,000 years ago. Further evidence puts modern humans in India and other parts of South Asia prior to the super-eruption of Mount Toba in Sumatra, which took place 74,000 years ago.

13 Jun 2013