Origin and Environmental Setting of Ancient Agriculture in the Lowlands of Mesoamerica

Abstract

Archaeological research in the Gulf Coast of Tabasco reveals the earliest record of maize cultivation in Mexico. The first farmers settled along beach ridges and lagoons of the Grijalva River delta. Pollen from cultivated Zea appears with evidence of forest clearing about 5100 calendar years B.C. (yr B.C.) [6200 (14)C years before the present (yr B.P.)]. Large Zea sp. pollen, typical of domesticated maize (Zea mays), appears about 5000 calendar yr B.C. (6000 yr B.P.). A Manihot sp. pollen grain dated to 4600 calendar yr B.C. (5800 yr B.P.) may be from domesticated manioc. About 2500 calendar yr B.C. (4000 yr B.P.), domesticated sunflower seeds and cotton pollen appear as farming expanded.

Microfossil evidence for pre-Columbian maize dispersals in the neotropics from San Andrés, Tabasco, Mexico

“…3 a-c). Maize phytoliths were lacking in the deepest sample (1,190 cm), a finding consistent with our original pollen study (7). Rondels as a whole constituted significant proportions of the phytolith assemblages from the samples where maize was identified, and many of the rondel types are those that commonly occur in maize but not teosinte (e.g., ''spooled'' kinds and rondels with undecorated tops and bottoms).…”

“…Many of the grass phytoliths are from bamboos (e.g., tall saddles, cross-shaped phytoliths diagnostic of bamboos), which probably derived from the forest understory or small natural tree fall gaps. A single burned phytolith was observed of the total of thousands scanned on the slides; this finding correlates with the charcoal curve generated for SAV-4, which showed presence of few charcoal particles at that time (7).…”

“…Because pollen grains of teosinte and maize can overlap in attributes such as size and axis to pore ratios (8), our original work at San Andrés failed to rule out the possibility that the cultivated Zea was teosinte. The pre-6,000 cal BP (5,200 RYBP) Zea pollen from San Andrés falls mostly in the 45-to 58-m-diameter size range, with two grains in the 74-to 76-m-diameter size range (7). Under Nomarski phase, these smaller grains exhibited distinctive columella characteristic of Zea grains, and they have thicker walls than the larger post-6,000 cal BP grains.…”

“…Our pollen data from San Andrés (7) indicated that Zea was present in coastal Tabasco by 7,100 cal BP (6,200 RYBP) (Fig. 1).…”

Reassessing Coxcatlan Cave and the early history of domesticated plants in Mesoamerica

“…Romero's, Valenzuela's, Coxcatlan, and Guilá Naquitz Caves thus constitute a clear present-day research challenge: to recover comparably well documented and carefully interpreted preceramic records of cultural development and subsistence change from other regions of Mesoamerica, particularly in lowland environmental zones. Excavation of waterlogged deposits at the marshy Gulf Coast San Andrés site (29) has recently indicated the existence of remarkably well preserved archaeobotanical assemblages in lowland settings. San Andrés also underscores the potential difficulties involved in adequately documenting and dating the initial appearance of domesticated plants (e.g., projecting the age and domesticated status of Zea pollen from sediment cores) and the Faustian lure of ephemeral interpretive overreach.…”