Culture and Ecology of Chaco Canyon and the San Juan Basin

The Classic Adaptation 201between front and rear rooms. The basic A.D. 900sground plan disappears, and Lekson (1984a:60, 69-71)asked whether people were aggregating in the greathouses at this time or whether the great housesassumed different functions. If these additions indicatedliving space, then population growth in PuebloBonito, for example, would be 2.25 percent-a numberthat is thought to be considerably higher than the0.1 to 0.5 percent that Hassen (1981) suggests isnormal, and the 0.3 percent that Hayes (1981) estimatesoverall for Chaco Canyon. Lekson thoughtthat some people still lived in the larger houses andthat there trIaY have been a deciease in srraall=sitepopUlation at this time. Construction units were builtto the same scale as during the previous period, butconstruction episodes occur more often and indicategreater labor needs.The peak of construction occurred between A.D.1075 and 1115, when six major events took place(work on the East Wing and West Wing at PuebloBonito; the addition of a third-story row of storagerooms at Penasco Blanco; the North Wing, and theSouth Wing at Pueblo del Arroyo; and the constructionofWijiji). Rooms in the massive blocks tendto be interconnected on both axes. The interior roomslook more like storage rooms (standard rectangularrooms without firepits) than domestic spaces. Thisform, plus the presence of large, round rooms (kivas)enclosed within the room block, suggest public architecture.Lekson (1984a) noted that John Stein thoughtthat this ground plan is often associated with roadrelatedstructures in the San Juan Basin. After A.D.1110, similar units in Chaco Canyon were oftenlocated near buildings with long construction histories,at termini of roads, or at strategic points ofaccess to Chaco Canyon; e.g., the three earliest greathouses, and Pueblo Alto. Lekson suggested that thisperiod represents the formalization of a regionalnetwork. Although each construction event was threeto four times larger than those in previous constructionphases, these were sequential events occurring as oneevery seven to 10 years. The yearly labor input,therefore, was only twice that of the previous period.Lekson (1984a:63) asked whether this labor investmentrepresented kin groups or regional corvee labor.Based on Lekson's (1984a:261) estimates, thelargest construction event-the East Wing of PuebloBonito (stage VIB)-wouldhaverequired 193,000 manhours. A crew of 30 could have accomplished thistask if they worked a lO-hour day, 30 days per monthfor 20.8 months, over a lO-year period that includedthree years devoted only to construction. Althoughcorvee labor would not have needed many skills to accomplishthis feat, labor would have to have beenwell-organized to schedule the cutting and transport oftimbers, quarrying of stone, and construction. Becausethese buildings had evidence for better builtwalls that would require less upkeep and many interiorrooms with restricted access, Lekson (1984a:66)considered a change in function of these great housesfrom elite residence to storage with some elite residence.He proposed that a public function was addedto these buildings. He concluded that the centralcanyon during this period was an urban, regionalcenter, which represents significant complexity withinthe larger regional system (Lekson 1984a:71). (SeeChapter 8 for a discussion of the region.)During the early A.D. lIDOs, the presence oftrash in a number of rooms at Pueblo Alto, PuebloBonito, and Chetro Ketl was interpreted as indicativeof habitation at these large sites; and there are a numberof contemporary small sites in use. The appearanceof additional storage facilities and specializedbuildings (e.g., tri-walled structures, road ramps)suggest different functions for various facilities and anincrease in the institutions present in this society.Lekson suggested that by this time the overalladministration of the larger system was alienated fromthe local elite; and a higher level of administrationbecame effective when Chaco Canyon became thecenter of a single, basin-wide entity that participatedin long-distance trade that included the importation ofmacaws and copper bells. Based on his estimatedpopulation of 2,100 to 2,700 people in the centralcanyon, Lekson recognized that this number waslarger than any documented historic pueblo and thatthe level of social complexity was probably morehierarchical than that of the historic pueblos.Unfortunately, the data from studies of architecturecannot provide more than these hints to answerquestions about social complexity.Around A.D. 1110, or 1115 to 1140, constructiondecreased to former levels. There was somebuilding at existing sites, but most of the workresulted in new sites distinguished by McElmo-stylemasonry (e.g., New Alto, Kin Kletso, Casa Chiquita,