Origin: A Genetic History of the Americas

by Jennifer Raff

While traveling southward through the interior of the continent would have required serially encountering and adapting to new ecosystems (mountains, deserts, plains), people traveling southward via the coast would have had reliable access to food resources with which they were already familiar. Coastal resources are fairly consistent regardless of latitude, and people would have encountered similar ecosystems along the Pacific coast from Southeast Alaska to Tierra del Fuego. In recognition of the significant role that nutritionally valuable and abundant seaweeds might have played in a coastal dispersal, this ecological model has come to be known as the Kelp Highway hypothesis (30). While much more work needs to be done to fully test the ecological hypothesis, it’s supported by the fact that people who lived at Monte Verde ate algae and seaweed over 14,000 years ago and by the dietary evidence associated with Shuká Káa that we discussed at the very beginning of this book.