Preceramic Adoption of Peanut, Squash, and Cotton in Northern Peru

584

351

Questions that still surround the origin and early dispersals of maize (Zea mays L.) result in large part from the absence of information on its early history from the Balsas River Valley of tropical southwestern Mexico, where its wild ancestor is native. We report starch grain and phytolith data from the Xihuatoxtla shelter, located in the Central Balsas Valley, that indicate that maize was present by 8,700 calendrical years ago (cal. B.P.). Phytolith data also indicate an early preceramic presence of a domesticated species of squash, possibly Cucurbita argyrosperma. The starch and phytolith data also allow an evaluation of current hypotheses about how early maize was used, and provide evidence as to the tempo and timing of human selection pressure on 2 major domestication genes in Zea and Cucurbita. Our data confirm an early Holocene chronology for maize domestication that has been previously indicated by archaeological and paleoecological phytolith, starch grain, and pollen data from south of Mexico, and reshift the focus back to an origin in the seasonal tropical forest rather than in the semiarid highlands.early Holocene ͉ maize domestication ͉ phytoliths ͉ starch grains

Section: Discussionmentioning

confidence: 97%

Starch grain and phytolith evidence for early ninth millennium B.P. maize from the Central Balsas River Valley, Mexico

Piperno

Ranere

Holst

et al. 2009

584

351

“…They also add to the increasing archaeological and molecular evidence attesting to a primary role of seasonal tropical forests from Mexico to Brazil in the origins and dispersals of New World domesticated crops (e.g., 9,15,23,26,32).…”

Section: Discussionmentioning

confidence: 99%

The cultural and chronological context of early Holocene maize and squash domestication in the Central Balsas River Valley, Mexico

Ranere

Piperno

Holst

et al. 2009

224

119

Molecular evidence indicates that the wild ancestor of maize is presently native to the seasonally dry tropical forest of the Central Balsas watershed in southwestern Mexico. We report here on archaeological investigations in a region of the Central Balsas located near the Iguala Valley in Guerrero state that show for the first time a long sequence of human occupation and plant exploitation reaching back to the early Holocene. One of the sites excavated, the Xihuatoxtla Shelter, contains well-stratified deposits and a stone tool assemblage of bifacially flaked points, simple flake tools, and numerous handstones and milling stone bases radiocarbon dated to at least 8700 calendrical years B.P. As reported in a companion paper (Piperno DR, et al., in this issue of PNAS), starch grain and phytolith residues from the ground and chipped stone tools, plus phytoliths from directly associated sediments, provide evidence for maize (Zea mays L.) and domesticated squash (Cucurbita spp.) in contexts contemporaneous with and stratigraphically below the 8700 calendrical years B.P. date. The radiocarbon determinations, stratigraphic integrity of Xihuatoxtla's deposits, and characteristics of the stone tool assemblages associated with the maize and squash remains all indicate that these plants were early Holocene domesticates. Early agriculture in this region of Mexico appears to have involved small groups of cultivators who were shifting their settlements seasonally and engaging in a variety of subsistence pursuits.agricultural origins ͉ Mesoamerican preceramic ͉ maize domestication

“…One cannot underestimate the significance of squash and bottle gourds to humans. Utilitarian bottle gourds and edible squashes are among the first cultivars in the Americas (16,17). On the Peruvian coast, bottle gourds are common in preceramic contexts and closely associated with maritime subsistence as net floats (1).…”

mentioning

confidence: 99%

Gourd and squash artifacts yield starch grains of feasting foods from preceramic Peru

Duncan

Pearsall

Benfer

2009

In a study of residues from gourd and squash artifacts, we recovered starch grains from manioc (Manihot esculenta), potato (Solanum sp.), chili pepper (Capsicum spp.), arrowroot (Maranta arundinacea), and algarrobo (Prosopis sp.) from feasting contexts at the Buena Vista site, a central Peruvian preceramic site dating to Ϸ2200 calendar years B.C. This study has implications for the study of plant food use wherever gourds or squashes are preserved, documents the earliest evidence for the consumption of algarrobo and arrowroot in Peru, and provides insights into foods consumed at feasts.