A Multidisciplinary Approach to Understanding the Initial Introduction of Maize into Coastal Ecuador

167

The Central American isthmus was a major dispersal route for plant taxa originally brought under cultivation in the domestication centers of southern Mexico and northern South America. Recently developed methodologies in the archaeological and biological sciences are providing increasing amounts of data regarding the timing and nature of these dispersals and the associated transition to food production in various regions. One of these methodologies, starch grain analysis, recovers identifiable microfossils of economic plants directly off the stone tools used to process them. We report on new starch grain evidence from Panama demonstrating the early spread of three important New World cultigens: maize (Zea mays), manioc (Manihot esculenta), and arrowroot (Maranta arundinacea). Maize starch recovered from stone tools at a site located in the Pacific lowlands of central Panama confirms previous archaeobotanical evidence for the use of maize there by 7800 -7000 cal BP. Starch evidence from preceramic sites in the less seasonal, humid premontane forests of Chiriquí province, western Panama, shows that maize and root crops were present by 7400 -5600 cal BP, several millennia earlier than previously documented. Several local starchy resources, including Zamia and Dioscorea spp., were also used. The data from both regions suggest that crop dispersals took place via diffusion or exchange of plant germplasm rather than movement of human populations practicing agriculture.agricultural origins ͉ crop dispersals ͉ Neotropics ͉ starch grain analysis W ith the advent of molecular studies directed toward understanding the phylogenetics of various economic plants throughout the world, the domestication hearths of several major crop plants have been identified (e.g., refs. 2-5). However, tracing the dispersal of these domesticates, and the economic transition from foraging to food production by the societies that domesticated or adopted them, remains firmly dependent on the recovery of identifiable archaeobotanical remains. The development and application of microbotanical techniques in archaeology has led to major advances in investigating plant use and subsistence in regions where preservation of macrobotanical remains (seeds, fruits, tubers) is poor. In the Americas, phytoliths, pollen, and most recently starch grains, have provided substantial empirical evidence demonstrating the considerable antiquity of food production and crop dispersals in tropical regions once considered peripheral to agricultural origins. Numerous studies now show that people were experimenting with horticulture and moving domesticated plants around tropical forests by 9500-7500 cal BP, ¶ and that food production concentrating on a few particularly productive cultigens was widespread throughout the Neotropics by 5500 cal BP (6-14).The Isthmus of Panama forms a relatively narrow landbridge between North and South America, and was the terrestrial route for the dispersal of numerous domesticates. Not surprisingly, some of the earliest evidence for the spre...

Section: Discussioncontrasting

confidence: 64%

Starch grain evidence for the preceramic dispersals of maize and root crops into tropical dry and humid forests of Panama

Dickau

Ranere

Cooke

2007

167

“…(4,6). Despite this, others have concluded from their research that maize was not introduced into coastal Ecuador until Ϸ4150-3850 cal B.P., was used first and foremost in ceremonial contexts as a fermented beverage, and was not important in everyday subsistence (11,12). Further, some question the dependability of associated dates for documenting the presence of maize and the timing of its dispersal from Mexico (13); thus, our results are pertinent to this debate as well.…”

mentioning

confidence: 78%

Directly dated starch residues document early formative maize ( Zea mays L.) in tropical Ecuador

Zarrillo

Pearsall

Raymond

et al. 2008

131

The study of maize (Zea mays L.) domestication has advanced from questions of its origins to the study-and debate-of its dietary role and the timing of its dispersal from Mexico. Because the investigation of maize's spread is hampered by poor preservation of macrobotanical remains in the Neotropics, research has focused on microbotanical remains whose contexts are often dated by association, leading some to question the dates assigned. Furthermore, some scholars have argued that maize was not introduced to southwestern Ecuador until Ϸ4150 -3850 calendar years before the present (cal B.P.), that it was used first and foremost as a fermented beverage in ceremonial contexts, and that it was not important in everyday subsistence, challenging previous studies based on maize starch and phytoliths. To further investigate these questions, we analyzed every-day cooking vessels, food-processing implements, and sediments for starch and phytoliths from an archaeological site in southwestern Ecuador constituting a small Early Formative village. Employing a new technique to recover starch granules from charred cooking-pot residues we show that maize was present, cultivated, and consumed here in domestic contexts by at least 5300 -4950 cal B.P. Directly dating the residues by accelerator mass spectrometry (AMS) radiocarbon measurement, our results represent the earliest direct dates for maize in Early Formative Ecuadorian sites and provide further support that, once domesticated Ϸ9000 calendar years ago, maize spread rapidly from southwestern Mexico to northwestern South America.ceramic residues ͉ microfossil analysis ͉ AMS radiocarbon measurement ͉ crop dispersals ͉ agricultural origins

“…9 and 10 for a review of the data). **The suggestion that maize moved into northern South America shortly before 4,000 cal BP, based on phytoliths recovered from a small sample of early fourth millennium BP pottery from Ecuador (63), is unsupportable in light of the accumulated data. …”

Section: Methodsmentioning

confidence: 99%

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

Pohl

Piperno

Pope

et al. 2007

The history of maize (Zea mays L.) is one of the most debated topics in New World archaeology. Molecular and genetic studies indicate that maize domestication took place in tropical southwest Mexico. Although archaeological evidence for the evolution of maize from its wild ancestor teosinte has yet to be found in that poorly studied region, other research combining paleoecology and archaeology is documenting the nature and timing of maize domestication and dispersals. Here we report a phytolith analysis of sediments from San André s, Tabasco, that confirms the spread of maize cultivation to the tropical Mexican Gulf Coast >7,000 years ago (Ϸ7,300 calendar years before present). We review the different methods used in sampling, identifying, and dating fossil maize remains and compare their strengths and weaknesses. Finally, we examine how San André s amplifies the present evidence for widespread maize dispersals into Central and South America. Multiple data sets from many sites indicate that maize was brought under cultivation and domesticated and had spread rapidly out of its domestication cradle in tropical southwest Mexico by the eighth millennium before the present.phytoliths ͉ pollen ͉ paleoecology ͉ radiocarbon