Abstract:
:The timing of human colonization of East Polynesia, a vast area lying between Hawai'i, Rapa Nui, and New Zealand, is much debated and the underlying causes of this great migration have been enigmatic. Our study generates evidence for human dispersal into eastern Polynesia from islands to the west from around AD 900 and contemporaneous paleoclimate data from the likely source region. Lake cores from Atiu, Southern Cook Islands (SCIs) register evidence of pig and/or human occupation on a virgin landscape at this time, followed by changes in lake carbon around AD 1000 and significant anthropogenic disturbance from c. AD 1100. The broader paleoclimate context of these early voyages of exploration are derived from the Atiu lake core and complemented by additional lake cores from Samoa (directly west) and Vanuatu (southwest) and published hydroclimate proxies from the Society Islands (northeast) and Kiribati (north). Algal lipid and leaf wax biomarkers allow for comparisons of changing hydroclimate conditions across the region before, during, and after human arrival in the SCIs. The evidence indicates a prolonged drought in the likely western source region for these colonists, lasting c. 200 to 400 y, contemporaneous with the phasing of human dispersal into the Pacific. We propose that drying climate, coupled with documented social pressures and societal developments, instigated initial eastward exploration, resulting in SCI landfall(s) and return voyaging, with colonization a century or two later. This incremental settlement process likely involved the accumulation of critical maritime knowledge over several generations.
journal_name
Proc Natl Acad Sci U S Aauthors
Sear DA,Allen MS,Hassall JD,Maloney AE,Langdon PG,Morrison AE,Henderson ACG,Mackay H,Croudace IW,Clarke C,Sachs JP,Macdonald G,Chiverrell RC,Leng MJ,Cisneros-Dozal LM,Fonville T,Pearson Edoi
10.1073/pnas.1920975117subject
Has Abstractpub_date
2020-04-21 00:00:00pages
8813-8819issue
16eissn
0027-8424issn
1091-6490pii
1920975117journal_volume
117pub_type
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