Monday, September 1, 2014

The Baure's Linked Canoe and Road Transport System

dugout canoes in Baures region, upper Amazon, Bolivia
Contemporary Baure dugout canoes on the upper Amazon in Bolivia. (Click any image to enlarge.) Source.
The Baure people live between the San Martin, San Joaquin, and Negro Rivers -- upper reaches of the Amazon River system -- in northern Bolivia, near Brazil. The region is mostly savanna, cut through by navigable rivers and streams and with many wetlands and lakes. During the 3-5 month rainy season, the flat savanna and pampas grassland is completely covered by water. As the rainy season ends and the water recedes, the land gradually dries out to support agriculture and grazing.

The Baure people now number less than10,000, but when first described by Jesuit missionaries in the sixteenth century, they were more numerous, living in hundreds of towns on slightly elevated sections of land that naturally support patches of forest dotting the otherwise flat landscape. According to archaeologist Clark L. Erickson, each town was ruled by a hereditary chief, and the towns “had large public plazas with a large men's house or temple in the center. Around the plaza were hundreds of houses arranged along streets and wide avenues. Deep defensive moats and tall palisade walls surrounded many settlements.” Between the towns, raised agricultural fields were built up above the floor of the savanna. Altogether, the area was a "densely populated region filled with large, well- organized dispersed settlements."

Between about 2,000 BP and the time of European contact, the Baure built thousands of raised roads between their towns, totalling tens of thousands of linear miles. Radiating like spokes from every town, these roads connected the towns to one another and to surrounding raised-field farms. They were perfectly straight, often 3 (and occasionally as much as 7) miles long, and no more than a meter high – just high enough to raise the road surface above the seasonal floodwaters. Usually 12-15 feet wide, they were occasionally as wide as 60 feet. They were of simple packed earth construction, the material for which was excavated immediately adjacent to the road itself on one or both sides, creating a network of canals alongside each road.

recreation of precolumbian Baure road/canal complex
Roads carrying foot traffic and canals floating dugout canoes worked in parallel in precolumbian Baure culture. Source.
The road-canal system served multiple functions. The roads were, of course, used for communication and trade. Road travel may also have had important ceremonial or social significance, and the roads may have served as property or territorial boundaries. The roads also likely functioned as dikes to keep certain areas dry and/or to maintain stocks of water in others (for fish empoundments, example), and the canals would have been used to control the flow of water for these functions.

The roads themselves were often built in parallel to and relatively close to one another, so that as many as four roads might connect two towns. This was probably redundant for transportation needs, but it makes sense for the purposes of water control, demarcation of land rights, and possibly ceremonial purposes. Lacking any monumental architecture, the Baure may have viewed their roads – the result of large-scale communal effort – as the equivalent of individual municipal monuments, and the vast road-and-canal network might have served that purpose on a culture-wide basis.

Dugout canoes are in use to this day in the Baures region, and it is almost certain that they were used on the canals for transportation in the precolumbian era. Dugouts made possible the movement of larger quantities of agricultural produce and trade goods than could have been efficiently carried by manpower on the roads. (The Baure had no draft animals or wheeled vehicles.) The canals would have retained enough water for canoe travel long after the savannas dried out at the end of the rainy season, and many of them connected to navigable rivers, expanding the transportation network even further and linking the Baure to distant areas in the Amazon system.

Pre-Columbian Roads of the Amazon, Clark L. Erickson, from the publication Expedition, published by Penn Museum (date unknown)
Prehispanic Earthworks of the Baures Region of the Bolivian Amazon, Arqueologist Wilma Winkler Verlarde and Dr. Clark L. Erickson, a project of the Instituto Nacional de Arqueologia de Bolivia and the University of Pennsylvania Museum