Organic materials from the Huitzilapa shaft tomb (calibrated and averaged to date around a.d. 74 [Ramos and López 1996]) were examined for clues to identify the contents of food (or other types of) offerings and determine the constituents of burial accoutrements found on and around the six inhumations found in the two tomb chambers. These materials have been examined by light microscopy and scanning electron microscopy. The food offerings have proven difficult to identify. Only class (fish, insect) or kingdom level identifications (plant, animal) have been possible with available technology. Nevertheless, both the diversity of offering constituents and the quantity offered provide clues about the social status of the individuals interred in the tomb. The fibers of burial accoutrements have been less difficult to identify. Cotton and agave fibers and at least two other tentatively identified fiber types are associated with the interments and represent clothing, burial shrouds, and personal accoutrements. A crumpled piece of amate paper is associated with the high-status individual in the south chamber. This piece of paper is the earliest organic evidence of paper in Mesoamerica. The presence of cotton in the north chamber also suggests that cotton was a high-status item that had limited availability in the Jaliscan altiplano and was restricted to individuals that had achieved recognized social status. The predominance of agave fibers associated with all but one of the interments indicates the preeminence of maguey as the utilitarian fiber in western Mexico during the Late Formative. The association of paper with a male individual suggests that the Late Formative inhabitants of Huitzilapa recognized status differences and observed class differentiation and craft specialization. In addition to these organic, presumably food offerings, textiles, and fiber, a new species of bacterium—Bacillus tequilensis—was discovered in the decomposing material associated with the interments.

Cobs of the earliest known archaeological maize from San Marcos Cave in the Tehuacan Valley were reexamined to estimate their morphological similarity to extant Mexican maize races. Cursory examination of these 7,000-year-old specimens aroused suspicion that they are not very closely related morphologically to any thus-far-described modern Mexican race. Statistical comparison of the Tehuacan specimens with 30 races of Mexican maize fully confirmed this suspicion. However, the inclusion in our statistical analysis of an extant race of popcorn from Argentina morphologically similar to the Tehuacan specimens indicated that the two were virtually indistinguishable. These findings imply that the earliest maize from Tehuacan already was fully domesticated, its cobs exhibiting a morphology one would expect had maize evolved from teosinte by way of catastrophic sexual transmutation (Iltis 1983).