Rapid evolution of ritual architecture in central Polynesia indicated by precise ²³⁰ Th/U coral dating

Abstract

In Polynesia, the complex Society Islands chiefdoms constructed elaborate temples ( marae ), some of which reached monumental proportions and were associated with human sacrifice in the ‘Oro cult. We investigated the development of temples on Mo‘orea Island by 230 Th/U dating of corals used as architectural elements (facing veneers, cut-and-dressed blocks, and offerings). The three largest coastal marae (associated with the highest-ranked chiefly lineages) and 19 marae in the inland ‘Opunohu Valley containing coral architectural elements were dated. Fifteen corals from the coastal temples meet geochemical criteria for accurate 230 Th/U dating, yield reproducible ages for each marae , and have a mean uncertainty of 9 y (2σ). Of 41 corals from wetter inland sites, 12 show some diagenesis and may yield unreliable ages; however, the majority (32) of inland dates are considered accurate. We also obtained six 14 C dates on charcoal from four marae . The dates indicate that temple architecture on Mo‘orea Island developed rapidly over a period of approximately 140 y ( ca. AD 1620–1760), with the largest coastal temples constructed immediately before initial European contact (AD 1767). The result of a seriation of architectural features corresponds closely with this chronology. Acropora coral veneers were superceded by cut-and-dressed Porites coral blocks on altar platforms, followed by development of multitier stepped altar platforms and use of pecked basalt stones associated with the late ‘Oro cult. This example demonstrates that elaboration of ritual architecture in complex societies may be surprisingly rapid.

Precise chronology of Polynesian temple construction and use for southeastern Maui, Hawaiian Islands determined by 230Th dating of corals

“…It is also instructive to compare our results of 230 Th dating of Kahikinui temples with a similar set of dates obtained from another Polynesian locality, that of Mo'orea Island in the Society Islands archipelago. Sharp et al (2010) obtained 47 230 Th dates on corals from 22 temples (marae) on Mo'orea, including three large coastal temples associated with the island's highest-ranking elites, and 19 temples in the interior of the 'Opunohu Valley. In the Mo'orea temples, the dated corals were used primarily as architectural elements such as facades in the altar (ahu) platforms.…”

“…Nonetheless, it is certain that corals had ritual significance in a number of Polynesian societies (Rowland, 2007); for example, coral blocks were incorporated into the facades of temple altars in the Society Islands (Sharp et al, 2010). For Hawai'i, the nineteenth-century Hawaiian author Malo (1951:175) describes a rite associated with the luakini or king's war temple, during which the participants purified themselves by bathing in the ocean, then "carried with them pieces of coral, which they piled up outside of the heiau" (see also Handy, 1927:281;Valeri, 1985:319).…”

High-precision radiocarbon dating shows recent and rapid initial human colonization of East Polynesia

“…Conversely, linguistic similarity, often used to trace phylogenetic relationships of populations in East Polynesia according to a longstanding model of relatively slow, incremental expansion (24), now needs to be reconsidered in terms of specific founder effects and isolation, especially in the case of Rapa Nui. Similarly, the rise of monumental, ceremonial architecture within a much shorter regional chronology (25) implies a different kind of historical development as well as likely continuity with comparable structures in western Polynesia (12,26). Finally, the remarkable artifact similarities documented in the "archaic East Polynesian" assemblages of the Societies, Marquesas, New Zealand, and other islands reflect homology of forms (e.g., in fishhooks, adzes, and ornaments) with late and rapid dispersals over the region A B Fig.…”

Identifying residences of ritual practitioners in the archaeological record as a proxy for social complexity

“…Gambier Is demonstrated how monumental religious structures are embedded within settlement landscapes, and have outlined the pace and timing of temple construction sequences and labor requirements (Graves and Cachola-Abad, 1996;Kolb, 1991Kolb, , 1994Kolb, , 2006Kirch et al, 2015;Mulrooney and Ladefoged, 2005;Sharp et al, 2010;Weisler et al, 2006). Others have focused on cosmological layouts in temple orientation (Kirch, 2004;McCoy, 2008) and their associations with particular deities or astronomical events or how their architectural elements speak to religious beliefs.…”