An Unexplored Realm in the Heartland of the Southern Gulf ... - Famsi

2000a; Stark 1991). This apparent insulation from outside intrusion will be demonstrated
throughout the remainder of the chapter.
At El Marquesillo, the San Juan River is the interface between two ecological
communities, rolling uplands and low alluvial plains (see Castri 1992). The interface
contains a greater than usual range of species, a situation attractive to hunters (see Coe
and Diehl 1980, Appendices 1 and 2:157-187 for a comprehensive listing of regional
flora and fauna). The west bank of the river, where the site is located, is an elevated
prominence of a Miocene Epoch geologic feature that rises 8-12 m above the river
(Figure 3.2). The east bank of the river is a low-lying alluvial plain, marked by levees and
oxbow lakes. Annual alluvial flooding of the lower east bank creates excellent
opportunities for agricultural production that results in high yields, and the inundations
overflow the banks and levees transforming the extensive lowlying plains into veritable
lakes that, in the past, teemed with aquatic resources (Coe 1981; Coe and Diehl 1980b).
Figure 3.2. Illustration of the cut bank at El Marquesillo. The site is situated
atop the bank and is well above the flood stage river levels.
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