Shifting trade Routes May Have Been Root Cause Of Mayan Decline
May 24, 2012

Shifting Trade Routes May Have Been Root Cause Of Mayan Decline

Brett Smith for

The end of the classic Mayan civilization in the lowlands of Mesoamerica was likely expedited by shifting trade routes that started to bring valuable goods to coastal regions instead of the inland city-states of the ancient Native Americans.

While the cause of this decline is still shrouded in mystery, most scholars consider the period of the Maya Collapse to be between the 8th and 9th centuries. During this time, the highly sophisticated societies that existed along the rivers of northern Guatemala, southern Yucatan, and western Belize were slowly abandoned.

Researchers from The Field Museum and the University of Illinois, both located in Chicago, have uncovered a key piece in solving the mystery surrounding this collapse. According to their study published in the online version of Antiquity, factors like climate change, breakdowns in leadership, and warfare contributed to the collapse-- but shifting exchange networks may have been a key factor in the decline.

"Our research strongly suggests that changing patterns of trade were instrumental in prompting the 'Maya collapse'," said Gary Feinman, curator of anthropology at The Field Museum and co-author of the study.

Since they did not have metal tools, the Maya highly valued obsidian because of its sharp edges for use as cutting instruments. Maya rulers and aristocrats derived power from controlling access to obsidian, which could be traded for important goods or used in negotiations. Researchers identified a few sources of obsidian in their study including three in Guatemala and several sources in both central Mexico and Honduras.

By tracking the trade flow of obsidian, Field Museum researchers found that prior to the fall of the Maya inland centers, the volcanic glass tended to flow along inland river networks. But over time, this material began to be transported through coastal trade networks instead, with a corresponding increase in Mayan coastal centers' prominence as the inland centers declined.

"The implication is that other valuable goods important to these inland centers were also slowly being cut off,” said the study´s lead author Mark Golitko.

Using Social Network Analysis (SNA) software, Golitko and his team developed maps illustrating which sites had the same or similar percentages of different sources of obsidian, during the different periods of Mayan history. These percentages were then utilized to infer the likely network structures through which obsidian was traded.

The resulting SNA maps show that between 250 and 800 A.D., trade networks were located along the inland rivers of the ancient empire. However, maps bearing data from later time periods show that inland networks shrank and coastal networks were thriving, in what is today the northern Yucatan and coastal Belize.

"The use of SNA to display and analyze the obsidian data graphically gives us a new perspective on these data, some of which has been present for years,” said Feinman.

A discovery earlier this month revealed just how sacred and important obsidian was to the ancient people of Mesoamerica. Mexican anthropologists found human tissue and blood cells on obsidian knives collected at the Cantona site, located in the southern Mexican state of Puebla. This fortified city flourished around the same time as the Maya, from 600 to 1000 A.D.