What was more surprising to the researchers was the lack of seafood in the diet of the islanders. "Traditionally, from Polynesian cultures you have a heavy predominance of using marine products, especially in the early phase of colonization," said Amy Commendador, of the Idaho Museum of Natural History at Idaho State University, in an interview with LiveScience.
One reason for the lack of seafood may have to do with the island's location and topography, Commendador said. The northern end contains steep cliffs and would be difficult to fish from. Additionally, the island's southerly latitude makes it somewhat cooler and may affect fishing. "Because of their geographic location and climate conditions, there just weren't as many marine products for them to get," Commendador said.
Rats should not be underestimated in their value as a resource, study co-author John Dudgeon, also at Idaho State University, told LiveScience. They could eat anything and multiply rapidly within a few generations. For the people who lived on Rapa Nui, "it was probably easier to go get a rat than it was to go get a fish," Dudgeon said.
Though the study results showed the islanders' diet was mainly terrestrial, a few individuals, dating after A.D. 1600, appeared to have been eating more fish than the others. [The 7 Perfect Survival Foods]
These fish eaters may have lived on a part of the island where the fishing was easier, Commendador suggested. Another possibility the team raises in their paper is that access to marine resources varied due to the social and political constraints people faced. For the islanders, eating fish might have been a mark of "higher status" individuals, an elite person who was allowed more plentiful access to seafood.
One curious coincidence is that most of the Moai, the statues erected by the islanders, face inland rather than out to sea. Now, this new research suggests the people of the island also turned inland, rather than to the sea, to get their food.
Commendador and Dudgeon don't think any direct relationship between the Moai statues and the islanders’ diet exists. Previous research has suggested the statues were positioned facing inland due to ancestor worship, so that the statues could watch over their descendents.
Another, more speculative, idea is that by having the statues facing inland, the islanders were also "saying we're turning inwards and not turning outward," Dudgeon said. While this probably doesn't relate to the islanders' decision to eat rats rather than fish, it shows the mindset the people of Rapa Nui may have developed before the arrival of Europeans. Their lifestyle as well as their diet may have become focused on the land rather than the sea.
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Original article on LiveScience.