Ancient crops of Polynesian and South American origin prior to European contact have been identified in the oldest archaeological site on Easter Island, a remote Chilean territory in the Pacific Ocean.
The research, published in the journal PLOS One, presents evidence that there were ancestral contacts between the peoples of the Pacific islands and the populations of South America, separated by thousands of kilometers.
The study, led by archaeologist Andrea Seelenfreund, from the Academy of Christian Humanism University, sought to reconstruct the subsistence practices of the Rapa Nui society during the first stages of colonization and settlement on the island.
For this purpose, starch grains that come from the surface of obsidian tools from the earliest levels of the Anakena site were analyzed. Starch grains were identified from the fruit of the breadfruit tree (Artocarpus altilis), from other species of origin in Oceania and various crops of South American origin.
The settlement of the Pacific was one of the great feats of humanity, since it involved the colonization of a maritime territory that covers almost a third of the planet’s surface. The exploration and colonization voyages by Polynesian navigators were not limited to discovering almost all of the Pacific islands, but also reached the coasts of America.
One of the survival strategies used by the ancestors of the current Pacific peoples between 3,000 and 1,000 years ago was the intentional transfer of economically important animals and plants in the canoes of the colonizing groups, in order to ensure their survival and reproduce. your culture. This set of actions is known as “transported landscapes.” This strategy was of vital importance, given that islands increasingly distant from a continent are progressively poorer in terrestrial natural resources.
The Polynesians were great navigators and for several centuries crossed the ocean in all directions, transporting plants and other goods. It is estimated that more than 70 different species of plant species were intentionally introduced into the Pacific. The species transported (whether animals, plants or microorganisms) intentionally (or not) had very different origins. Some species are native to continental Asia, others come from Southeast Asia, and others are native to New Guinea.
In the case of Rapa Nui, oral tradition tells in detail the provision of different species of plants to undertake the colonization of the island. The new research sought to reconstruct the subsistence practices of Rapa Nui society during the early stages of colonization and settlement on the island. For this, starch grains recovered from obsidian tools from the oldest site dated to Rapa Nui were analyzed. This corresponds to the lower layer of the Anakena site, which was excavated in 1986 by a Norwegian team. The tools found come from a context dating from the period between 1000-1300 AD. C. and until now represents the evidence of the oldest human settlement on this island. The tools analyzed were housed in the warehouse of the Rapa Nui Museum and the study consisted of the analysis of starch grains, of microscopic size, recovered from the surface of twenty obsidian tools.
The results allowed the identification of starch grains belonging to plant taxa of traditional crops on the Pacific Islands, including Rapa Nui. Among these crops, taro (Colocasia esculenta) and yam (Dioscorea sp.) stand out, both common species in Pacific agriculture. Starch grains from Polynesian crops for which there was no previous record on the island were also identified, such as the breadfruit tree (Artocarpus altilis), and the tropical trees Spondias dulcis and Inocarpus fagifer.
Not only were typical species from Oceania identified, but starch grains from crops of American origin were also identified. Among them was the sweet potato (Ipomoea batatas), a species that had already been documented in archaeological contexts on other Pacific islands. In this case, the context of the Anakena site clearly places the presence of sweet potatoes on Rapa Nui to a period long before the European presence in the Pacific. The detection of sweet potato grains (I. batatas) at the early level of the Anakena site on Rapa Nui thus constitutes the oldest record of this cultigen in the Pacific.
In this study, starch grains from species for which there were no previous records in archaeological sites on other Oceanian islands were also identified, such as achira (Canna sp.), cassava (Manihot esculenta) and taro (Xanthosoma sp.), three species of native American tubers from tropical and subtropical areas. The presence of starch grains from these species suggests the translocation of South American crops to the Pacific, a finding not previously described.
In light of the findings, Andrea Seelenfreund explains in a statement that “the introduction of these South American species strongly suggests that some type of contact was established between Polynesian navigators and the populations of the South American coasts. Our findings provide the first evidence that these species may have been introduced much earlier than previously thought, as part of a suite of South American crops that reached the Pacific during return voyages from the Americas. Most likely, the species chosen for the return journey were those whose edible parts could be easily transported.”
He then adds that “by including a set of South American tubers in our comparative collection, we provide the first empirical evidence that the sweet potato was not the only food transported from America to the Pacific in times of pre-European contact.”