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One of the key locations to examine the history of human settlement in Lagoa Santa is the site of Lapa do Santo, a rockshelter known to contain the oldest rock art and the earliest evidence of funerary complexity in the continent.
During the last prehistoric expansion of modern humans, Polynesians from the Samoa-Tonga area dispersed through more than 500 remote, subtropical to subantarctic islands of East Polynesia (a cultural region encompassing the islands of New Zealand, Chathams, Auckland, Norfolk, Kermadecs, Societies, Cooks, Australs, Gambier, Tuamotu, Marquesas, Line, Rapa Nui, and Hawaii), an oceanic region the size of North America (Fig. The timing and sequence of this expansion, debated vigorously since Europeans rediscovered the islands of East Polynesia (1, 2) and most intensively with the advent of radiocarbon dating (3, 4), remains unresolved. This analysis shortened East Polynesian prehistory just at the time when accelerator mass spectrometry (AMS) radiocarbon dating became available for very small samples (e.g., individual seeds).(EDS) offers streamlined access to all of your library's resources from a single search.The 15 archipelagos of East Polynesia, including New Zealand, Hawaii, and Rapa Nui, were the last habitable places on earth colonized by prehistoric humans.That is, to accept only those dates that () are capable of providing a calibration that is close to the “true” age of the actual target event (i.e., human activity).One approach is to evaluate dates within their individual and comparative stratigraphic levels according to criteria of “chronometric hygiene” (11, 12) and build from those results toward a regional overview; but this method can be subjective, and it is impractical when dealing with very large databases, as is the case here.Islands of East Polynesia, summarizing the two phases of migration out of West Polynesia (blue shading): first to the Society Islands (and possibly as far as Gambier) between A. ∼10 (orange shading), and second to the remote islands between A. It used a “chronometric hygiene” protocol to exclude dates with high uncertainty and to provide a chronology that proposed initial settlement A. Conflicting estimates for initial colonization in East Polynesia create great uncertainty about the historical framework within which human mobility and colonization, variations in human biology and demography, and the rates and types of human-induced ecological impacts to island ecosystems must be explained.
As the number of radiocarbon dates from East Polynesia has increased 10-fold over those available in 1993 (5), an attempt to resolve the frustrating problem of colonization chronology for the region is now opportune.
Our main objective is to establish the most accurate age, or ages, for initial colonization in East Polynesia.
To accomplish this, it is necessary to be conservative in evaluating the usefulness of data.
The timing and pattern of this colonization event has been poorly resolved, with chronologies varying by 1000 y, precluding understanding of cultural change and ecological impacts on these pristine ecosystems. We show that previously supported longer chronologies have relied upon radiocarbon-dated materials with large sources of error, making them unsuitable for precise dating of recent events.
In a meta-analysis of 1,434 radiocarbon dates from the region, reliable short-lived samples reveal that the colonization of East Polynesia occurred in two distinct phases: earliest in the Society Islands A. ∼1025–1120, four centuries later than previously assumed; then after 70–265 y, dispersal continued in one major pulse to all remaining islands A. Our empirically based and dramatically shortened chronology for the colonization of East Polynesia resolves longstanding paradoxes and offers a robust explanation for the remarkable uniformity of East Polynesian culture, human biology, and language.
, the Orchidaceae lack a definitive fossil record and thus many aspects of their evolutionary history remain obscure.