Prehistoric Maize in the Northern Andes: Pollen and Diatom Analyses of the Lake San Pablo Core, Ecuador

International Archaeological Research Institute, Inc., Honolulu HI

Investigators

Abstract

Before the time of Columbus in 1492, maize was "the grain that civilized the New World." Prehistoric maize farming societies were found throughout much of the vast continental areas of North and South America except in the most extreme environmental zones, and truly advanced social systems occurred in a number of areas. With National Science Foundation support, Dr. J. Stephen Athens seeks to contribute to an understanding of how and why maize rose to such importance during prehistoric times by analyzing lake sediment cores from northern highland Ecuador. This northern South American study region, situated in a temperate valley surrounded by presently and previously active volcanoes, is known for its high agricultural productivity and the traditional dependence on maize by its past and present indigenous populace. The study cores are expected to contain long Holocene records of maize pollen preserved in the sediments. The deepest appearance of distinctive maize pollen grains in the cores will indicate, along with radiocarbon dating, when it was first introduced to the region. Combined with other regional studies, this information will help signal not only the timing, but the path of the spread of maize south from Colombia and, ultimately, southwestern Mexico, its apparent place of origin 7000 to 8000 years ago. In addition, the study of diatoms, which are the microscopic remains of certain types of unicellular algae having silica shells, will serve to document the rise and fall of lake levels, in effect providing a long term proxy record of regional rainfall. This will help to determine the specific environmental conditions under which the introduction and adoption of maize agriculture occurred in the mountains of northern highland Ecuador, as well as changing climatic conditions that prehistoric agriculturalists may have had to confront through time. Related questions of interest this study will seek to address include 1) whether or not the appearance of maize coincides with the earliest appearance of agriculture in the northern highland region of Ecuador, or if maize actually post-dates initial agriculture; 2) the trajectory of the prehistoric intensification of maize cultivation over time; 3) the change of the natural landscape of the highland valley to a virtually entirely man-made landscape; and 4) an evaluation of the possible effect of major volcanic ash falls on the ecology and environment of the inter-Andean valley and the time required for recovery (e.g., is there evidence that humans abandoned the valley for a significant period following major eruptions?). The significance of the research is that it will advance our understanding of the history of the single most important New World agricultural domesticate, contributing to a baseline of information for the spread of maize from Mesoamerica and its adoption by indigenous prehistoric societies in the northern Andes. Information on the history of maize in the northern Andes heretofore has been sketchy at best, and there have been very few detailed studies of its history of use at any single location. In addition, the study will provide a long term perspective on climatic fluctuations, the natural environment, and human ecology in a region that is presently densely populated. Such information may contribute to the development and guidance of a variety of public policy issues besides being of scientific interest to several disciplines.