A celestial father and an earthly mother entwined had many children, one of whom separated his parents to let in the light, according to traditions of Maori origin. In a version told to Maori archaeologist Gerard O’Regan of the Ngāi Tahu tribe, an unborn child remains in the womb, its eyes or whatpeering like rocks, or kowhatu, a Maori word for stone. These words serve as a reminder that everything from rivers and animals to stars and people can trace their ancestry to such connections in Maori worldviews.
Elsewhere in Polynesia, a reconstruction of the word is *pofatu, said Aymeric Hermann, an archaeologist at the French National Center for Scientific Research. He is also co-creator of the Pofatu Database, a compilation of geochemical information gleaned from stone tools and quarries from sources scattered throughout the Pacific that can be matched to each other.
“Looking at the chemistry of the [stone artifacts] lets you know who the people are [were] in communication with, how often and over what period of time,” said Marshall Weisler, an archaeologist at the University of Queensland in Australia, who provided data to Pofatu.
The settlement of the Pacific is “the greatest migration over water in human history,” Weisler said, “and we see the end of it in Polynesia – the last places on Earth that have been settled by humans.” (apart from Antarctica, of course).
Languages, cultures and creation stories share striking similarities across Polynesia, which spans the vast region between Aotearoa (New Zealand), Hawaii and Rapa Nui (Easter Island) – the vertices of the Polynesian Triangle . Yet when Europeans arrived in the Pacific in the 1600s, they didn’t observe much inter-island travel, Hermann said. It wasn’t until the 1970s that Polynesians rediscovered their ancestors’ knowledge of navigating thousands of miles of high seas using only the signs of nature.
By collecting and analyzing the geochemistry of stone adzes (a type of woodworking tool) and dating the layers from which they come, archaeologists can examine the frequency of artifacts from outside their found location, a Weisler said. On islands near and far from an adze site, source quarries range from bedrock to boulders.
For example, the Cook Islands is home to a rock shelter that has been occupied for about 400 years. At first, Weisler explained, the artifacts came not only from local sources, but also from Samoa and the Marquesas Islands, thousands of miles away. Over time adzes from afar have diminished, likely because community concerns shifted from expensive travel to prioritizing land use and agriculture. This same pattern of early and extensive communication abroad that is fading throughout Polynesia, an analysis has revealed.
In another example, the Tuamotus – a thousand kilometer line of low-lying atolls in French Polynesia – contain no volcanic source rock for adzes. Any volcanic adze found there, Weisler said, must have come from elsewhere. The astonishing variety of springs goes from as far away as Pitcairn and Hawaii, the latter being 4,000 kilometers away with nothing but the open ocean in between. Geochemistry has confirmed that the Tuamotus, he says, are “the crossroads of Eastern Polynesia”.
Successfully matching source to stone “is really a niche part of archeology that requires geological expertise,” said Kekuewa Kikiloi, a Hawaiian archaeologist at the University of Hawai’i at Mānoa not affiliated with the Pofatu Project. .
This matching is what the Pofatu database aims to facilitate, Hermann said, because it selects both source geochemical data and artifacts. Once peer-reviewed studies have been published, he said, authors can send him data through the Pofatu website, which he updates two to three times a year. Several experts in the geochemical supply of archaeological materials in the Pacific have already contributed to the data they have published, including Weisler and John Sinton, a geochemist at the University of Hawai’i at Mānoa. In the 2 years since its inception, no studies have been published using Pofatu, although some are forthcoming, Hermann said.
The Pofatu database includes information obtained from destructive and non-destructive techniques. “The most accurate way to analyze rock is with a destructive technique,” Sinton said. Destructive techniques include a type of X-ray fluorescence (XRF) which requires relatively large aliquots of rock powders and inductively coupled plasma-mass spectrometry (ICP-MS), which typically requires minute amounts of a sample to be dissolved. Non-destructive techniques involve a different type of XRF that has also been exploited in a portable instrument for field work. “Archaeologists favor [nondestructive methods] for good reasons,” Sinton said. “They don’t want to destroy valuable artifacts.”
In Weisler’s lab, they use dental burs — the ones that remove cavities from your mouth — to get milligrams of powder with minimal destruction for ICP-MS analysis. “I’ve been one of the most outspoken people against uniquely non-destructive use [geochemical methods],” he said. Analyzes of basalt artifacts that often show broadly similar chemical signatures require a wider range of modern tools, he argued: The farther adze material can come from, the further it there may be potential sources, “so [in many cases] much more sophisticated and powerful geochemical techniques must be used” than those offered by non-destructive technologies.
Analyze a life force
“When we [Māori] look at a rock, the rock is not a completely inanimate object,” said O’Regan, who is also curator of Maori at the Otago Museum. “Rock,” he said, “has a life force.” For Maori, who often review requests for destructive and non-destructive testing on different aspects of heritage, “even though some of the invasive testing can be really tiny…we wonder if it has an impact on the Mauri [life force]?”
Although Maori may want to know more about their ancestors, the spiritual aspects of the stone (which derive partly from origin stories and partly from the ancestors who may have handled it) must be balanced with learning which may come from analysis, O’Regan said. . He noted that learning science can potentially deepen cultural connection.
However, this connection to the past can also make Aboriginal people feel “that it’s their grandfather’s stuff that [archaeologists] are digging,” Kikiloi said. This is especially true when researchers use destructive techniques on artifacts. Kikiloi said he would be hesitant to use Pofatu, instead preferring datasets that don’t include any destructive methods. (The University of Hawaii at Hilo has such a facility.)
In addition to concerns about destructive versus non-destructive methods, O’Regan has expressed concern about how researchers use and contribute to the public database as a whole. In particular, he said the databases could lead researchers to look at questions of Polynesian archeology without working directly with Polynesian communities, unlike Hermann and Weisler. “You can look at Indigenous community after Indigenous community,” O’Regan said, “and none of them will say they weren’t negatively affected by someone else’s interpretation of them. at one point.
—Alka Tripathy-Lang (@DrAlkaTrip), science writer