We all know about those famous heads on Easter Island, but their origins are still largely a mystery.
These large stone structures are known to be one of the great question marks for archaeologists around the world.
The remarkable works of art have long been the centre of interest, as some experts have drawn the large bodies to works of the Polynesian population.
Known as moai, some ambitious conspiracy theorists have gone as far as suggesting that extraterrestrial life forms were responsible for creating the monolithic structures.
In a study published in the journal Antiquity, radiocarbon dating was used to track the spread of these and other ritual monuments across remote islands in the Pacific Ocean – to find when and where this activity actually began.
Easter Island is the only area of Polynesia that has these large structures (Micheline Pelletier/Corbis via Getty Images)
What are the Easter Island heads?
Known by locals as 'Moai', these structures were believed to be built on Rapa Nui (Easter Island) by the Rapa Nui people, located in eastern Polynesia.
The discovery of these structures on this far-off island located in the Pacific Ocean threw people off for years following their discovery by European travellers in the 18th century.
Measuring approximately 13 feet in height while weighing anywhere between 12-14 tons, the human heads sculpted on torsos are believed to have been made from hardened volcanic ash.
The largest Moai ever made is Paro, which was nearly 33 feet tall with a weight of 82 tons.
There are also unfinished structures known as 'El Gigante', which would have been much larger, at heights of 71 feet while weighing a colossal 150 tons.
It is said that there are over 1,000 of these 'Moai' statues dotted around the island.
What do we now know?
In a study published by Paul Wallin and Helene Martinsson-Wallin via the Cambridge University Press, it was suggested that people on Easter Island were in contact with other Polynesian islands thousands of miles away.
Wallin and Martinsson-Wallin used radiocarbon dating across the region, finding that ritual activity began in western Polynesia before spreading east between 1000 and 1300 CE.
These started with single upright stones to mark ceremonial sites, with the tradition spreading to Easter Island in the east last, as it was the final island to be populated.
While it was widely believed that the island was cut off from networks of communication for centuries, it was found through the scientific method that a second wave of ritual construction may disprove this.
The Easter Island heads have thrown archaeology experts for centuries (Getty/Carlos Aranguiz) When did these changes happen?
A second wave of ritual construction took place between 1300 and 1600, this time involving more formal architecture with stone platforms known as marae or ahu.
However, these structures originated on Easter Island itself, before spreading west this time.
Speaking to IFLScience, Professor Wallin admitted that while early settlement reached the island around 1200 CE, they were responsible for the 'existing dates of the formalised marae'.
"It’s about 160 that we have looked through – we easily find early-dated ahu temple grounds on Rapa Nui,” he stated.
These popped up on the island between 1300 and 1400 CE, before appearing in other areas of Central and East Polynesia, and the Cook Islands, from 1400 CE onwards.
It suggests that this ritual complex was invented on Easter Island, dispelling the belief that the land was completely isolated.
In fact, a third wave of ritual construction further backs this up, as massive monuments built on Easter Island would spread across the rest of Polynesia.
The study noted that this took place on the island from 1350 CE onwards, before being built in other areas such as Hawaii in the 16th century.
Wallin also mentioned that genetic evidence pointed towards the Rapa Nui people having contact with South America, adding: "If they could do that, then they were very skilled sailors and could go the other way as well, to Mangareva (west of the island) or something.”
He labels the idea of isolation as 'strange' when it comes to Easter Island.