Research Results

The purpose of this research is to answer many questions about the conditions and the significance of the Alaskan coast during and shortly after the Last Glacial Maximum. How extensive were the glaciers that flowed out of the mountains to the east? Was all the land covered by ice and essentially uninhabitable, or were there ice-free coastal refugia that supported large animal communities? Did arctic animals reach southern Alaska, or were the Ice Age communities composed of temperate animals that managed to survive the cold? Did they feed on terrestrial plants or exclusively from the ocean? How well did Ice Age animals survive in competition with new immigrants when the ice melted? And the question asked probably more than any other: could humans have lived along the Alaskan coast during the Ice Age, and could this have been their first route into the New World?

Below is a map of Southeast Alaska showing the proposed extent of glacial ice during the Last Glacial Maximum (in red) based on a variety of data collected by many researchers (see http://instaar.colorado.edu/QGISL/ak_paleoglacier_atlas for additional maps). Glacial reconstructions such as this are helping to identify ice-free areas to search for fossil deposits, such as the western side of Coronation and Dall Islands. Note that all of Prince of Wales Island is interpreted to have been covered by ice, including On Your Knees Cave which contains many fossils dating to the Last Glacial Maximum. What is not yet known is the exact timing, duration, and thickness of ice cover in specific areas. These are questions that the fossil record is helping to resolve. Ice may have been thick and long-lasting in some areas, but ephemeral in other locations.

Answering historical questions requires a historical record. Prior to this research, ideas about coastal refugia and coastal migration in Ice Age Alaska were subjects of mere speculation. Thanks to the discovery of well-preserved fossils by a dedicated group of cavers, Forest Service scientists, and researchers, we have begun to answer some of these tantalizing questions. Below are links to several pages that contain tables and photos and that discuss the preliminary research conclusions, primarily of the animal record of Prince of Wales Island. This research is ongoing. Extensive laboratory work is still underway on materials collected over the past decade, and the work of finding and excavating cave sites is expanding to the outer islands of the Alexander Archipelago and to other areas of Southeast Alaska. More information will be provided as it becomes available.

  Mammal Fossils   Radiocarbon Dates
Bird Fossils Stable Isotopes
Fish Fossils Publications

The question of whether humans first entered North America by a coastal route is far from resolved. But we are much closer to answers than we were a decade ago. Two important conclusions can be drawn from this research: 1) The animal record (under study by Dr. Tim Heaton and Fred Grady) demonstrates that coastal Southeast Alaska contained ice-free land areas and was inhabited by an extensive community of terrestrial and marine mammals and birds during all of the Last Glacial Maximum. This implies that humans could easily have survived there. 2) The archaeological record (under study by Dr. James Dixon and his colleagues), though not the earliest in the Americas, demonstrates that people were present in coastal Alaska much earlier than previously thought and had already discovered the major resources of the region by about 10,000 years ago. This makes the Northwest Coast a very likely route for first entry into the Americas. As we continue our research and explorations, an even older human record may be found.

   
© 2002 by Timothy H. Heaton