Climate Model Suggests Timeline for Migration to North America

MENLO PARK, CALIFORNIA—Live Science reports that a possible coastal migration route along the Bering Strait Land Bridge that once connected Asia and North America may have only been passable between 24,500 and 22,000 years ago, and 16,400 and 14,800 years ago. Paleoceanographer Summer Praetorius of the U.S. Geological Survey and her colleagues used data on sea ice variations and sediment samples from the Gulf of Alaska to develop a model of climate change over the past 45,000 years. The model included the conditions of sea ice, glacier size, ocean currents, and food supplies along the suggested North Pacific coast route. The study suggests that migrants traveling during the winter in these windows of time would have been able to traverse flat sea ice cover and hunt seals and whales. During the summers, migrants would have found plentiful food in kelp forests and would have been able to travel by boat on ice-free waters without encountering strong currents from melting glacial ice or hazardous calving icebergs, Praetorius explained. Read the original scholarly article about this research in Proceedings of the National Academy of Sciences of the United States of America. For more, go to "A Seaside Journey to America."