Polynesian migration theories challenged by new University of Auckland research

Early Polynesians likely arrived in the south Pacific from a range of routes through Southeast Asia, mixing with populations along the way, new research has found.

Researchers at the University of Auckland studied the 193 Neolithic period (10,000 to 4500 BCE) carbon dates on ceramics from 20 archaeological sites in island Southeast Asia. They found there was an "extraordinary" mixing of populations as people moved further south into the Pacific, rather than via two distinct routes that unfolded step-by-step.

They say their findings challenge theories suggesting either Polynesian migrants set out from Taiwan and moved into Southeast Asia before heading further south - the 'Out of Taiwan' theory - or the earliest farming and pottery-using populations came from mainland Southeast Asia in the west, before going further south - the 'Western Route Migration' hypothesis.

These two theories are linked to competing explanations of the Austronesian expansion, which is one of the most significant population dispersals in the ancient world that influenced human and environmental diversity from Madagascar to Easter Island and Hawai'i to New Zealand.

Study lead Ethan Cochrane, archaeologist and associate professor says the research suggests this time period involved the most "mixing, matching and moving" of people around the region in all of human pre-history - and no clear linear routes south emerge.

"It seems that island Southeast Asia was a huge mixing pot of people rather than two clear routes, either from the north, or the west, and then down into the southern Pacific.

"Our data supports the idea that people moved in all directions at a range of times, as there are pieces of this earliest pottery from exactly the same era deposited in both western Borneo and the northern Philippines, for example, which couldn't be the case if the existing theories are correct."

Ethan Cochrane.
Ethan Cochrane. Photo credit: Supplied / University of Auckland

Cochrane says the team's results are the most accurate chronological calculations based on currently available data but admits in general, the carbon dating of pottery from inland Southeast Asia isn't as precise as it could be.

But he believes it's clear from the existing data the origin of Polynesian people, the early ancestors of Māori, and other Pacific island nations is "a much more complex story of the mingling of people, languages and cultures".

"As we generate more accurate and precise dates, we can begin to explore the implications of this new way of thinking about early human movement around the Earth, which has shaped continuous variation in past populations and might also change how contemporary Polynesian people think about their own origins," Cochrane says.

The study has been published in PLOS One.