Ancient Chesapeake Site Challenges Timeline of Humans in the Americas

An island eroding into the bay offers tantalizing clues about when and how humans first made their way into North America

Unearthing History in the Chesapeake Bay

With the Chesapeake Bay lapping at his knee-high boots, Darrin Lowery surveyed a 10-foot-tall bluff rising above a narrow strip of beach. To the untrained eye, this wall of sandy sediment is an unremarkable edge of a modest island southeast of the Bay Bridge. However, for Lowery, a coastal geologist, its crumbling layers place the island at the center of one of archaeology's most contentious battles: when and how humans first arrived in the Americas.

In a photograph taken before the coronavirus pandemic necessitated social distancing and the wearing of masks, Neeshell Bradley-Lewis (right), a master’s level student at UD working with Darrin Lowery (left), an affiliated professor in the Department of Earth Sciences, examine the stratigraphy — a branch of geology concerned with the study of rock layers and layering — on Parson’s Island.

The story of the first Americans has long fascinated both the public and scientists, often igniting fierce debates. Over the past century, the timeline of human arrival in the Americas has gradually shifted earlier, with a general consensus now placing it at least 15,000 years ago. Yet, discoveries at Lowery's site and similar locations could push this timeline back even further, challenging long-held beliefs.

Discovering Ancient Artifacts

Lowery and his team have discovered 286 artifacts on Parsons Island’s southwestern edge. The oldest of these artifacts was found embedded in charcoal dated to over 22,000 years ago—a period when much of North America was covered by ice sheets. If verified, this finding could revolutionize the understanding of American prehistory, raising new questions about early human migration patterns.