We present macrobotanical, starch, and phytolith data from artifacts and sediments from Middle Formative La Blanca (1000–600 cal BC) and Late Formative El Ujuxte (600 cal BC–cal AD 115 ) in the Soconusco region in Guatemala. Potential economic plants identified included palm (cf. Arecaceae), two varieties of maize (Zea mays), guava (Psidium guajava), bean (Phaseolus), chili peppers (Capsicum), squash (Cucurbitaceae), custard apple (Annonaceae), coco plum (Chrysobalanaceae), lerén (Calathea), arrowroot (Maranta), and bird-of-paradise (Heliconia). The results suggest that control of food production and consumption was critical for the transition from complex chiefdoms during the Middle Formative to the archaic state in the Late Formative. The arrival of a more productive South American variety of maize at El Ujuxte (about 2549 BP) allowed elites to exploit an already existing broad-based economic system and to use the maize-based religious system to increase control over maize agricultural practices and maintain power through ideology and disciplinary power. These data suggest that the arrival of fully domesticated South American maize likely influenced the overall development of Mesoamerican state-level societies.

This study uses isotope and microbotanical data from the analysis of teeth and dental calculus to investigate camelid diet and foddering practices at Quilcapampa (AD 835–900). By providing taxonomically specific evidence of foods consumed, botanical data from dental calculus complement the more general impressions of photosynthetic pathways obtained through isotopic analysis. Results suggest that the camelid diet incorporated maize (Zea mays), algarrobo (Prosopis sp.), potato chuño (Solanum sp.), and other resources. The life-history profile of one camelid (Individual 3) reveals dietary change from mainly C3 plants to more C4 plant contributions as the animal aged. This pattern is supported by carbonate isotope results indicating that this individual spent its youth in the mid-valley ecozone before becoming more mobile later in life. As this life-history example shows, isotopic and microbotanical analyses are complementary approaches, clarifying a pattern of seasonal transhumance that linked the lives of humans and animals along the Middle Horizon (AD 600–1000) caravan networks that crisscrossed the central Andes.

We investigated foodways at Real Alto, an early Formative (4400–1800 BC) Valdivia site in coastal Ecuador, using starch and phytoliths recovered from 50 stone tools from three residential and two ceremonial structures, as well as 46 human dental calculus samples, to explore how food reflects the social relationships and economy of the community. Maize was important in daily meals and ceremonial foods by the Middle Valdivia (2800–2400 BC), but it was only one component of an agricultural system that included yuca, arrowroot, llerén, canna, yam, jackbean, squash, gourd, chili, and cotton. Ceremonial and everyday foods at Real Alto did not differ: actions surrounding food were both domestic and ceremonial, depending on context. Households had equal access to annual crops and to root-tubers with longer growing seasons. Gelatinized starch was commonly recovered on tools, indicating the processing of cooked foods. Dental calculus residues confirmed common consumption of cooked foods, fruits, and root-tubers. Cultivating crops with different water and growing season requirements necessitated diverse practices, potentially including selection of short-season varieties, hand watering, and growing crops over multiple rainy seasons. The latter two practices required increased labor inputs: access to labor was likely a key element supporting the nascent social hierarchy that emerged by the Middle Valdivia.