An analysis of stylistic variability of stemmed obsidian tools (MATA’A) on rapa nui (Easter Island)

Easter Island, or Rapa Nui as it is known in modern traditional terms, is a small (164 km 2), remote island situated in the southeastern Pacii c (Figure 12.1). The island is the easternmost edge of Polynesia, rel ecting the origin, culture, and language of the island’s native population. Rapa Nui is most famous for its hundreds of megalithic statues (moai) that were carved and transported, some over several kilometers of rough terrain, reaching nearly every part of the island. The scale of ef ort, and the investment represented, has bal ed visitors and researchers for centuries. Thus, emerged the so-called mystery of Easter Island: How and why did people on such a remote and impoverished island carve and transport these giant statues? A persistent and related theme has been the island’s prehistoric ecological devastation – a dimension that added to the mystic of enormous investment in the statues. The deforestation led early visitors and modern writers alike to speculate that human-induced ecological change led to population (and cultural) collapse. Jared Diamond (2005:6) called it “ecocide” for ecological suicide committed by the prehistoric islanders. Although not the subject of this chapter, we have shown that “ecocide” conl ates the historically separated consequences of prehistoric deforestation with post-European disease-induced population collapse (see Hunt and Lipo 2007, 2009). Part of the collapse narrative that developed, beginning with early visitors, was that the island suf ered constant conl ict, violence, and intergroup warfare leading to the imagined pre-European decimation of the population (e.g., Flenley and Bahn 2003). In this chapter, we examine mata’a, a class of lithic artifacts found in abundance on Rapa Nui. We consider how to build descriptions that enable us to study patterns of transmission among prehistoric populations. Such patterns of inheritance track social relations with implications for the evolution of groups, competition, and scale of sociopolitical organization, in this case among the prehistoric Rapa Nui population. Although these kinds of studies are often conducted using assemblages of decorated ceramics (e.g., Lipo et al. 1997), here we show how analysis of variability unconstrained by performance (style) allows us to measure aspects of inheritance related to the manufacture of these artifacts. In the case of mata’a from Rapa Nui, we demonstrate that it is possible to reach falsifiable conclusions about the evolutionary dynamics that shaped the archaeological record on this island.