Cassava Reality (1)

Manioc (Manihot esculenta)

Cassava (Manihot esculenta), also known as manioc, tapioca, yuca and mandioca, is a domesticated species of tuber, originally domesticated perhaps as long ago as 8,000-10,000 years ago, in southern Brazil along the southwestern border of the Amazon basin. Cassava is today a primary calorie source in tropical regions around the world, and the sixth most important crop plant worldwide.

The progenitor of cassava (M. esculenta ssp. flabellifolia) exists today and is adapted to forest and savanna ecotones. Archaeological evidence of cassava in the little-investigated Amazon basin has not been identified—the area was determined the point of origin based on genetic studies of cultivated cassava and various possible progenitors. The first archaeological evidence of manioc is from starches and pollen grains, after it was spread outside the Amazon.

Cassava starches have been identified in north central Colombia by ~7500 years ago, and in Panama at Aguadulce Shelter, ~6900 years ago. Pollen grains from cultivated cassava have been found in archaeological sites in Belize and Mexico's gulf coast by ~5800-4500 bp, and in Puerto Rico about 3300-2900 years bp.

There are numerous cassava and manioc species in the world today, and researchers still struggle with their differentiation, but recent research supports the notion that they are all descended from a single domestication event in the Amazon basin. Domestic manioc has larger and more roots and an increased tannin content in the leaves. Traditionally, manioc is grown in the field-and fallow cycles of slash and burn agriculture, where its flowers are pollinated by insects and its seeds dispersed by ants.

Sources

This glossary entry is a part of the About.com Guide to Domestication of Plants, and part of the Dictionary of Archaeology.

Dickau, Ruth, Anthony J. Ranere, and Richard G. Cooke 2007 Starch grain evidence for the preceramic dispersal of maize and root crops into tropical dry and humid forests of Panama. Proceedings of the National Academy of Sciences 104(9):3651-3656.

Léotard, Guillaume, et al. 2009 Phylogeography and the origin of cassava: New insights from the northern rim of the Amazonian basin. Molecular Phylogenetics and Evolution In press.

Olsen, K. M., and B. A. Schaal. 1999. Evidence on the origin of cassava: Phylogeography of Manihot esculenta. Proceedings of the National Academy of Sciences 96:5586–5591.

Piperno, Dolores R. and Irene Holst 1998 The Presence of Starch Grains on Prehistoric Stone Tools from the Humid Neotropics: Indications of Early Tuber Use and Agriculture in Panama. Journal of Archaeological Science 25(8):765-776.

Pohl, Mary D. and et al. 1996 Early agriculture in the Maya lowlands. Latin American Antiquity 7(4):355-372.

Pope, Kevin O., et al. 2001 Origin and Environmental Setting of Ancient Agriculture in the Lowlands of Mesoamerica. Science 292(5520):1370-1373.

Rival, Laura and Doyle McKey 2008 Domestication and Diversity in Manioc (Manihot esculenta Crantz ssp. esculenta, Euphorbiaceae). Current Anthropology 49(6):1119-1128

Zeder, Melinda A., Eve Emshwiller, Bruce D. Smith, and Daniel G. Bradley 2006 Documenting domestication: the intersection of genetics and archaeology. Trends in Genetics 22(3):139-155.