What animal bones tell us about the rise and fall of the Maya in Guatemala

STRI/DICYT More than 35.000 bone and shell fragments from a Maya settlement in Ceibal, Guatemala tell the tale of animal use through the ups and downs of a great civilization according to a new report in the journal PLOS One by Ashley Sharpe, staff archaeologist at the Smithsonian Tropical Research Institute, with colleagues from the University of Arizona, the University of Ibaraki, Japan and Guatemala’s Institute of Anthropology and History and Universidad de San Carlos.

One of the first Maya communities to build large monuments, the site of Ceibal was occupied nearly continuously for more than 2000 years, from about 1000 BC until 1200 AD.

“Because the excavations were so extensive in both time and space, the patterns we see, such as dramatic shifts in diet and ceremonial uses of animals, are not flukes, but likely represent the way the Maya were using resources both at Ceibal and are comparable with other reports across the region,” Sharpe said.

Bones decay quickly in the humid tropics. To recover such an exceptional number of well-preserved remains, members of the Ceibal-Petexbatun Archaeological Project suspended soil from the excavations in water and collected bone fragments as they floated to the top. They classified the fragments by comparing them to collections of identified animal bones.

"From the earliest remains almost three thousand years ago, we see many different dogs throughout the community, which at the time were the only domestic animals in Central America,” Sharpe said. “It is possible some were pets or used for hunting, but a few bones with cut marks could indicate that some were eaten.”

The team also discovered that the early residents of Ceibal were eating thousands of snails and mussels from the nearby river and wetlands. In one residential area dated to roughly 700-450 BC they found an adult male buried with hundreds of apple snails: perhaps evidence of his burial feast.

“In fact, our most intriguing result was a major shift around 2000 years ago from huge quantities of apple snails and mussel shells to far more fish, turtle and deer bones,” Sharpe said. “We are really curious to find out if this was just a shift in food preferences, or the result of habitat loss. There is evidence from sediment cores in northern Guatemala that there was a lot of deforestation and erosion during the Preclassic-Classic transition around 200 AD, which perhaps destroyed wetland habitats.”

Another interesting pattern was the increase in river turtle (Dermatemys mawii) bones after 200 AD. The largest freshwater turtle in the region, this critically endangered species is still considered a delicacy. In another Smithsonian study, zoologists suggested that the ancient Maya imported turtles from the Isthmus of Tehuantepec. Although this has yet to be confirmed by genetic analysis, the Ceibal results support this possibility.

Evidence of another imported species was identified from the few fragile bird bones that remained at the site: turkeys. Turkey bones appear at Ceibal after the Preclassic period, supporting the idea that people were bringing early domesticated turkeys from Central Mexico south into Guatemala. Sharpe’s isotope analysis on the turkey bones shows that by the end of the transition turkeys were eating corn, confirming that they were likely domesticated.

“Bones of both white-tailed and brocket deer were common throughout the history of the site but as Ceibal became an important political center and society became more socially stratified, we start finding more deer — sometimes a dozen in a single trash deposit,” Sharpe said. “Deer appear to be a favorite food of the Classic period elites and may have played a special role during feasts.”

There was other evidence for social stratification as well. Ceibal elites wore feline paws and skins on stelae. In a trash heap behind the royal palace, researchers discovered margay and kinkajou mandibles, the arm of an anteater, a bull shark tooth, and sea urchin spines, perhaps also the remains of costumes or other royal paraphernalia.

By comparison, the middle class had a more varied diet of local fauna, including rabbits, pacas, agoutis, possums, raccoons, weasels and armadillos, anteaters and even an occasional peccary or tapir.

“Then suddenly everything stopped around 950 AD during the famous ’Maya Collapse’ when all the cities were abandoned,” Sharpe said “Only a few people occasionally returned to the edges of the site in the centuries after that.”

Identifying the bones in this massive collection was just the first step. In the future, they hope to fine-tune their identifications of the numerous tiny fish at the site, use DNA to examine Maya dog breeds, and learn more about the lives of non-elites.

"The focus of Maya archaeology up until now has been large monumental sites, and especially the royal elites during the Classic period,” Sharpe said. “We hope to excavate residences and older sites to get a better idea of what society was like for the majority of the Maya people.”