"Marine Paleotemperatures and Paleoclimate as Factors in Late Holocene Occupation of Coastal Southern California" (with Mark Raab, senior author). American Antiquity, 16(2): 319-337, 1997.

Abstract Archaeologists have long viewed paleoenvironmental forces as both engines of change and limiting factors in prehistoric cultural systems. Like their colleagues throughout North America, California archaeologists attribute Holocene cultural transformations to major paleoenvironmental trends (Chartkoff and Chartkoff 1984; Moratto 1984). Only in the last two decades, however, have comparatively high-resolution paleoenvironmental records become available for the southern California coast. Even more recently have archaeologists employed these data in explanations of coastal cultural evolution. Our comments are on some of these efforts, focusing on possible effects of marine paleotemperature and precipitation trends during the late Holocene. An alternative explanation for the emergency of cultural complexity among coastal hunter-gatherer-fishers of prehistoric California is offered. We suggest that and increase population densities near the most productive habitat areas during a period of deteriating climatic conditions resulted in growth of large villages, greater dependence on intra-regional exchange of food and other material items, and increased raiding and warfare. These condition significantly influenced the tempo of culture change between A.D. 1050 and A.D. 1300.

Over the years, in my publications and papers presented at professional meetings, I have discussed the significance of climatic change on the course of human evolution. This article incorporates much of the climatic reconstruction work that I have been engaged in over the last several years for California. My previous work has been cited frequently in major publications on climatology and archaeology for California. I am happy to say that our recent work was the focus of Volume 62, No. 2, of American Antiquity . In the article that Mark Raab and I wrote, we argue that major climatic change was a primary driver of culture change in California between A.D. 800 to A.D. 1300. We analyzed several different data sets that demonstrated support for our position. This article takes exception to the long held popular view that political factors are the primary movers, as advocated by Jean Arnold at UCLA. This particular American Antiquity volume was very interesting because it included a new article by Jean Arnold and her comments on our article. This set of articles were particularly important because we each had a chance to critique each others article within the same issue--this is the first time (in a long time) such an opportunity was given to contributors of American Antiquity. This research is particularly valuable because a number of my students are doing their thesis work on the prehistory of California..