Easter Island people used sharpened stones as tools, not weapons

Obsidian artifacts challenge notion that warfare led to collapse of Rapa Nui civilization

obsidian tools

SPEAR NOT  A new analysis of obsidian artifacts from Easter Island indicates that these finds served as tools for planting and other daily activities. Some researchers have portrayed these implements as spearpoints that were used by warring island groups before Europeans arrived in the 1700s.

C. Lipo and Father Sebastian Englert Anthropological Museum, Rapa Nui

Sharpened stones previously viewed as spear points wielded by warring Easter Islanders actually served as general-purpose tools, researchers say.

Early European visitors to Easter Island, also known as Rapa Nui, wrote in the late 1700s that the islanders carried spears topped with sharp, triangular pieces of glassy lava, or obsidian. In the past 20 years, some researchers have suggested that fighting among spear-bearing groups — following the leveling of resource-rich palm forests around 1550 — destroyed Rapa Nui civilization before Europeans arrived.

But the Rapa Nui probably used the alleged spearpoints in a variety of ways that had nothing to do with killing each other, say archaeologist Carl Lipo of Binghamton University in New York and his colleagues. These sharp rocks, known as mata’a, would have been useful for tasks such as scraping and cutting sweet potato plants into pieces suitable for cultivation, cutting bananas off trees, stripping bark for rope and cutting ritual designs into people’s skin, perhaps to create tattoos, the scientists report in the February Antiquity.

Evidence of versatile uses for mata’a “adds to our understanding of how ancient Rapa Nui society flourished until well after initial European contact in 1722,” says anthropologist Mara Mulrooney of Bernice Pauahi Bishop Museum in Honolulu. Recent research suggests that farming on the island continued long after palm forests had been cleared (SN: 1/25/14, p. 9).

Mata’a had no standardized shape and rarely sported long, spearlike tips, Lipo’s team finds. These tools must have been fashioned with nonviolent purposes in mind, the scientists contend.

That conclusion rests on shape and size measurements taken from photographs of 423 mata’a. Most artifacts are held in museums on Rapa Nui or in Hawaii. There are no precise age estimates for the finds, but mata’a date to before Europeans reached Rapa Nui, Lipo says.

A statistical analysis identified no consistent tool shape among these finds. Mata’a feature narrow stems and wide blades, but vary considerably within that format. Neither did Lipo’s group detect a distinctive set of spear-shaped mata’a within the larger sample. Even mata’a made from rock gathered at the same Rapa Nui obsidian quarries — of which five exist — and fashioned at the same toolmaking locations lacked signature forms.

Microscopic studies published 20 years ago suggested that scratches, polish and chipping on mata’a resulted from woodworking, Lipo adds.

Previous research indicated that obsidian tools resembling mata’a were used to cut up root crops, carve wood and perform other daily tasks on the Melanesian island of New Britain several thousand years ago. Archaeologists Nina Kononenko of the University of Sydney and Robin Torrence of the Australian Museum in Sydney conducted that work.

Lipo’s new study can’t definitively rule out the use of mata’a as weapons, Torrence says. Although mata’a don’t look like spearpoints, “these stone implements would be very dangerous if used as axes or clubs in close-combat fighting,” she says.

Lipo considers that scenario unlikely. While any sharp-edged stone can be used on occasion to hurt others, no remains of hilltop forts or other defensive structures linked to warfare have been found on Rapa Nui, he says. Mata’a “were sharp rocks on sticks designed not as lethal weapons but for peaceful purposes,” Lipo says.  

Bruce Bower has written about the behavioral sciences for Science News since 1984. He writes about psychology, anthropology, archaeology and mental health issues.

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