In the long human migration that started in Africa 65,000 years ago, Homo sapiens expanded from a small population in what is now Ethiopia to populate all the habitable land on Earth. We know from archaeological and carbon dating evidence that the last significant land mass to be settled, just 750 years ago, was New Zealand. But where did those first settlers come from? Maori tradition says the ancestral waka came from the homeland of Hawaiki, but where is Hawaiki? Professor Lisa Matisoo-Smith, a biological anthropologist from the University of Otago and the Allan Wilson Centre for Molecular Ecology and Evolution, has been working on this puzzle for nearly two decades. “We use variations in mitochondrial DNA and Y chromosomes to track the migration histories of New Zealanders,” she says.
Mitochondrial DNA, or mtDNA, is inherited along maternal lines, and Y chromosomes along paternal lines. Genetic mutations accumulate over time and are passed down through generations, so the more mutations that two individuals have in common, the more closely they are related, and vice versa. Now, as reported last month in the Proceedings of the National Academy of Sciences, Matisoo-Smith is one step closer to finding Hawaiki. With permission from the Rangitane-ki-Wairau iwi, she and her colleagues have extracted and analysed genetic sequences from the teeth of a man and three women whose remains were recovered from New Zealand’s oldest archaeological site, on the Wairau Bar in Marlborough.
The site was home to a large village, dated to 1285-1300AD, where human remains were buried close to remains from now extinct species such as the moa and haast eagle, along with bones of elephant seals, sea lions and fur seals. Also found were carved artefacts and necklaces stylistically related to East Polynesian cultures, says Matisoo-Smith, “so prior to the development of unique Maori motifs and designs”. The remains have been dated at 700 years old and Matisoo-Smith says it looks like they “were within a generation or two of, if not the first colonists, who arrived on the shores of Aotearoa”.
One of the most significant of the team’s findings is the genetic diversity between the four individuals. “One thing we might have expected, given the matrilineal and matrilocal structure of ancient Pacific societies, is that perhaps these first settlers were sisters and their husbands, or people who are closely related, in which case we would see very little mtDNA variation. “So the fact that these individuals were not closely related on a maternal line was quite surprising. It means there were at least four maternal lineages among the four individuals, which is pretty diverse.”
Archaeological and linguistic evidence points to Hawaiki being somewhere in Central East Polynesia – a stretch of islands that includes the Cook Islands, the Society Islands and the Austral Islands. Researchers now hope to match the specific mutations found in the Wairau Bar individuals to other populations – contemporary and ancestral – in East Polynesia. “If we can narrow down those specific East Polynesian homelands that were the source of the founding population, we might find Hawaiki – or various Hawaikis.”