Culture and Ecology of Chaco Canyon and the San Juan Basin

A Broader Perspective 343that is related to differences in altitude. For mammals,there are many small-body-size animals withsmall home ranges and reduced niche distributions.Based on the hunter-gatherer ethnographic cases in thistype of environment, Binford (200I:Table 5.10)projected an average of 14.69 people per 100 km 2 ; anarea of 217.28 km 2 per group; a 42.76 percent dependenceon terrestrial plants; a mean household sizeof 6.17 people; a mean size of largest annual socialaggregation of 50.10 people; and an 8.36 averagenumber of annual residential moves per year forforaging groups.Based on available data (Gillespie's 1985: 18),the E. T. value for Chaco Canyon today would be13.53, which places it in the cool temperate zone. Itis within the storage threshold where one wouldexpect generic hunters 4-"d gatherers to SPend someperiods of time in collecting and preparing foods(either plant or animal) for use during the nonproductiveseason; e.g., gathering of pinon nuts onChacra Mesa (Wills and Windes 1989). However,there is considerable variability in topography withinthe larger region. Different E.T. values are expectedin these microhabitats. Binford (2001) listed a numberof E. T. values for more distant neighboringhunter-gatherer popUlations; they range from 13.59for the Kaibab Southern Paiute in Arizona (wherestorage is expected) to 15.83 for the Lipan Apache inTexas (where storage would not be needed).Based on current climatic conditions, which havebeen similar for the past 4,000 years (A. Johnson1997), there would have been no aquatic animals orlarge game on which to rely. Prior to that, there wasclimatic change at the end of the Pleistocene. Usingmethods refined by Reid Bryson (Bryson and Bryson1995) that depend on longitude, latitude, and elevation,high-resolution and site-specific models ofclimatic change could be reconstructed. By developingsuch reconstructions, it might be possible toaddress some questions. For example, did large gameanimals habitually use the San Juan Basin? What dothe few Paleoindian points recovered in Chaco Canyonrepresent? The rate of change in environmental conditionscould also be compared with the modelsdeveloped by Betancourt and VanDevender (1980) andHall (1977). If changes at the end of the Pleistocenemade it less risky for those dependent on terrestrialmammals to switch to plant food, it should be possibleto predict when the changes in technology (e.g.,switch from atlatI to bow and arrow) would appearand compare the predicted results with thearchaeological data.Based on areas of 217 . 28 km 2 per group dependenton terrestrial plants, the number of people livingin the San Juan Basin during the Preceramic periodmay not have been packed. There may have manyseparate groups that might have belonged to differentsegments, be they linguistic or cultural. How mightthese be correlated with Gwinn Vivian's (1990)delineation of four Archaic populations duringBasketmaker II? When might the threshold of 52.677persons per 100 km 2 be reached and mobility nolonger be an option for foragers dependent uponterrestrial plants? When might the threshold of304.99 persons per iOO km 2 be reached, at which nonrankedhunters and gatherers no longer exist? Becausethe Historic Pueblo people fall within the zone wherehunter-gatherer cases with the highest populationdensity were charted, what might this imply for thelevel of social complexity in Chaco Canyon and theSan Juan Basin during the Classic Bonito phase?Due to the low productivity for the area andfluctuating rainfall patterns, how might periods ofbetter rainfall alleviate population stress, which mightallow Pueblo horticulturalists to maintain nonrankedsocial organization during the Classic Bonito phase?Calculation of population density per 100 km 2 couldelucidate differences among communities, and perhapsindicate how the canyon differed from the rest of theSan Juan Basin. Could nesting of segments in the canyonhave reached a higher tier that brought togetherlarger work groups during certain occasions? Was themovement out of the Four Comers area a response inpart to the ability of Pueblo people to pursuesubsistence in wider niche breadth locations elsewhereand not necessarily a response to drought alone?After Pueblo people left the San Juan Basin, theregion was open for use by different people. InChapter 10, the issue of the earliest Navajo presencewas not resolved. Because no other populations wereliving in the region after A.D. 1300, would huntergatherershave been easily visible? With Young's (inCameron and Young 1986) ability to distinguishwhich lithic scatters are Archaic and which Navajo,would it be worthwhile to re-examine data from lithic