We might be closer to understanding what happened to the people of Easter Island – after new evidence suggests they didn’t recklessly destroy their own environment.
Several books have dwelt on the idea that the civilisation on the island declined before Europeans arrived – due to deforestation.
Now scientists believe the story isn’t quite that simple – and that other environmental factors may have been involved.
‘The traditional story is that over time the people of Rapa Nui used up their resources and started to run out of food,’ said Binghamton University Professor Carl Lipo.
‘One of the resources that they supposedly used up was trees that were growing on the island. Those trees provided canoes and, as a result of the lack of canoes, they could no longer fish.
‘So they started to rely more and more on land food. As they relied on land food, productivity went down because of soil erosion, which led to crop failures…Painting the picture of this sort of catastrophe. That’s the traditional narrative.’
Lipo and his team analysed remains of people, animals and plants from the sits Anakena and Ahu Tepeu, dating from 1400AD.
The researchers used bulk carbon and nitrogen isotope analyses of collagen isolated from human and animal bones, to work out what resources the people used to survive.
The results show where the inhabitants got their protein from – and it shows that the ‘traditional’ picture is wrong.
‘We found that there’s a fairly significant marine diet, over time, throughout history and that people were eating marine resources, and it wasn’t as though they only had food from terrestrial resources,’said Lipo.
‘We also learned that what they did get from terrestrial resources came from very modified soils, that they were enriching the soils in order to grow the crops.
‘That supports the argument we’ve made in our previous work, that these people came up with an ingenious strategy in enriching the soils by adding bedrock to the surface and inside the soil to crate, essentially, fertilizer to support their populations, and that forest loss really isn’t a catastrophe as previously described.’
‘The Rapa Nui people were, not surprisingly, smart about how they used their resources. And all the misunderstanding comes from our preconceptions about what subsistence should look like, basically European farmers thinking, ‘Well, what should a farm look like?’
‘And it didn’t look like what they thought, so they assumed something bad had happened, when in fact it was a perfectly smart thing to do. It continues to support the new narrative that we’ve been finding for the past ten years.’
So what did happen? One theory is that Polynesian rats may have wiped out the trees on the islands – leading to a severe change in the environment.