The History and Domestication of Cassava

Man carrying a cassava tree through a field.

Corbis / Getty Images

Cassava (Manihot esculenta), also known as manioc, tapioca, yuca, and mandioca, is a domesticated species of tuber, a root crop originally domesticated perhaps as long ago as 8,000–10,000 years ago, in southern Brazil and eastern Bolivia 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.

Fast Facts: Cassava Domestication

  • Cassava, commonly called manioc or tapioca, is a domesticated species of tuber, and the sixth most important food crop in the world. 
  • It was domesticated in the southwestern Amazon of Brazil and Bolivia some 8,000-10,000 years ago. 
  • Domesticate improvements include traits which must have been added by means of clonal propagation. 
  • Burned tubers of manioc were discovered at the classic Maya site of Ceren, dated to 600 CE. 

Cassava Progenitors

The progenitor of cassava (M. esculenta ssp. flabellifolia) exists today and is adapted to forest and savanna ecotones. The process of domestication improved the size and production level of its tubers, and increased the photosynthesis rate and seed functionality, by using repeated cycles of clonal propagation—wild manioc cannot be reproduced by stem cuttings.

Archaeological macro-botanical evidence of cassava in the little-investigated Amazon basin has not been identified, partly because root crops do not preserve well. Identification of the Amazon as the point of origin was based on genetic studies of cultivated cassava and all various possible progenitors, and the Amazonian M. esculenta ssp. flabellifolia was determined to be the wild form of today's cassava plant.

Amazon Evidence: The Teotonio Site

The oldest archaeological evidence for manioc domestication is from starches and pollen grains from sites outside the Amazon. In 2018, archaeologist Jennifer Watling and colleagues reported the presence of manioc phytoliths attached to stone tools at the southwestern Amazon Teotonio site in Brazil very near the Bolivian border.

The phytoliths were found in a level of dark earth ("terra preta") dated to 6,000 calendar years ago (cal BP), 3,500 years older than any terra preta anywhere else in the Amazon to date. The manioc at Teotonio was found alongside domesticated squash (Cucurbita sp), beans (Phaseolus), and guava (Psidium), indicating that the inhabitants were early horticulturalists in what is becoming recognized as an Amazonian center of domestication.

Cassava Species Around the World

Cassava (Manihot esculenta)
Cassava (Manihot esculenta), root and ground for dinner.  Rodrigo Ruiz Ciancia / Moment / Getty Images

Cassava starches have been identified in north-central Colombia by approximately 7,500 years ago, and in Panama at Aguadulce Shelter, about 6,900 years ago. Pollen grains from cultivated cassava have been found in archaeological sites in Belize and Mexico's Gulf coast by 5,800–4,500 bp, and in Puerto Rico between 3,300 and 2,900 years ago. Thus, scholars can safely say that the domestication in the Amazon had to happen before 7,500 years ago.

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 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.

Manioc and the Maya

Joya de Ceren, Guatemala
The "Pompeii" of North America, Joya de Ceren, was buried in a volcanic eruption in August 595 CE. Ed Nellis

Members of the Maya civilization cultivated the root crop and it may have been a staple in some parts of the Maya world. Manioc pollen has been discovered in the Maya region by the late Archaic period, and most of the Maya groups studied in the 20th century were found to cultivate manioc in their fields. The excavations at Ceren, a classic period Maya village that was destroyed (and preserved) by a volcanic eruption, identified manioc plants within the kitchen gardens. Manioc planting beds were discovered some 550 feet (170 meters) away from the village.

The manioc beds at Ceren date to approximately 600 CE. They consist of ridged fields, with the tubers planted on the top of the ridges and water allowed to drain and flow through the wales between the ridges (called calles). Archaeologists discovered five manioc tubers in the field which had been missed during harvesting. Stalks of manioc bushes had been cut into 3–5 foot (1–1.5 meter) lengths and buried horizontally in the beds shortly before the eruption: these represent preparation for the next crop. The eruption occurred in August of 595 CE, burying the field in nearly 10 ft (3 m) of volcanic ash.

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