How Did changing climate in the tropical South Pacific contribute to the eastward migration and settlement of Polynesia?

David Sear; Mark Peaple; Peter Langdon; Daniel Skinner; Manoj Joshi; Adrian Matthews; Charlotte Hipkiss; Tim Osborn; Gordon Inglis; Justin Shefield

doi:10.70460/jpa.v16i2.399

Authors

David Sear University of Southampton https://orcid.org/0000-0003-0191-6179
Mark Peaple http://orcid.org/0000-0002-4208-0104 https://orcid.org/0000-0002-4208-0104
Peter Langdon https://orcid.org/0000-0003-2724-2643
Daniel Skinner https://orcid.org/0000-0002-0086-5958 https://orcid.org/0000-0002-0086-5958
Manoj Joshi https://orcid.org/0000-0002-2948-2811 https://orcid.org/0000-0002-2948-2811
Adrian Matthews https://orcid.org/0000-0003-0492-1168 https://orcid.org/0000-0003-0492-1168
Charlotte Hipkiss https://orcid.org/0000-0001-6379-079X https://orcid.org/0000-0001-6379-079X
Tim Osborn https://orcid.org/0000-0001-8425-6799 https://orcid.org/0000-0001-8425-6799
Gordon Inglis https://orcid.org/0000-0002-0032-4668
Justin Shefield 0000-0003-2400-0630

DOI:

https://doi.org/10.70460/jpa.v16i2.399

Keywords:

Climate, Polynesia, Pacific

Abstract

The migration of humans into the eastern Pacific was relatively rapid and focused around 900-1250 CE. Although the causes for this migration are varied, we put forward evidence to suggest that a change in the mean state of the tropical South Pacific from La Niña like to El Niño like conditions accompanied by an increase in climate “shocks” around the period of migration, could have created conditions to promote migration east into the Pacific. We use a range of sediment archives and hydroclimate proxies located in sites within the region of migration, to reconstruct climate conditions in the ‘sending’ islands, and ‘receiving’ archipelagos. Climate in the period immediately prior to the eastward migration was characterised by a drier southwest Pacific. During the period following settlement of the central region of eastern Polynesia, the mean climate state in receiving islands became wetter, with fewer climate “shocks”. Results from socio-hydrological models highlight the sensitivity of growing populations to droughts within a drying climate. Using these lines of evidence, we suggest that as populations grew, particularly in drought-sensitive islands, people with some knowledge of eastern “Gateway islands”, chose to move east, fortuitously at a time when wetter conditions supported their long-term settlement.

References

Addison, D. J. 2006. "Feast or Famine? Predictability, Drought, Density, and Irrigation: the Archaeology of Agriculture in Marquesas Islands Valleys." PhD diss., University of Hawai‘i, Department of Archaeology & Anthropology.

Addison, D. J., and E. Matissoo-Smith. 2010. "Rethinking Polynesians origins: a West-Polynesia Triple-I Model." Archaeology in Oceania 45: 1–12. http://www.jstor.org/stable/20743940 DOI: https://doi.org/10.1002/j.1834-4453.2010.tb00072.x

Allen, M. S. 2006. "New ideas about Late Holocene climate variability in the central Pacific." Current Anthropology 47: 521–535. https://doi.org/10.1086/504168 DOI: https://doi.org/10.1086/504168

Allen, M. S., Lewis, T., & Porch, N. 2022. Lost bioscapes: Floristic and arthropod diversity coincident with twelfth century Polynesian settlement, Nuku Hiva, Marquesas Islands. PLoS ONE, 17,3. https://doi.org/10.1007/s10963-025-09189-1 DOI: https://doi.org/10.1371/journal.pone.0265224

Allen, M. S. 2010. "Oscillating Climate and Socio-Political Process: The Case of the Marquesan Chiefdom, Polynesia." Antiquity 84: 86–102. https://doi.org/10.1017/S0003598X00099786 DOI: https://doi.org/10.1017/S0003598X00099786

Allen, M. S., and R. Wallace. 2007. "New Evidence from the East Polynesian Gateway: Substantive and Methodological Results from Atiutaki, Southern Cook Islands." Radiocarbon 49: 1125–1148. https://doi.org/10.1017/S0033822200043095 DOI: https://doi.org/10.1017/S0033822200043095

Anderson, A. 2001. "No Meat on that Beautiful Shore: The Prehistoric Abandonment of Subtropical Polynesian Islands." International Journal of Osteoarchaeology 11: 14–23. https://doi.org/10.1002/oa.542 DOI: https://doi.org/10.1002/oa.542

Anderson, A. 2024. "The Origins of Prehistoric Sailing Technologies in the Pacific Ocean." In The Oxford Handbook of Island and Coastal Archaeology, edited by S. M. Fitzpatrick and J. M. Erlandson. New York: Oxford University Press.Anderson, A., J. Chappell, M. Gagan, and R. Grove. 2006. "Prehistoric maritime migration in the Pacific islands: an hypothesis of ENSO forcing." The Holocene 16, no. 1: 1–6. https://doi.org/10.1093/oxfordhb/9780197607770.013.3 DOI: https://doi.org/10.1093/oxfordhb/9780197607770.013.3

Atwood, A. R., D. Battisti, E. Wu, D. Frierson, and J. P. Sachs. 2021. "Data model comparisons of tropical hydroclimate changes over the common era." Palaeoceanography and Paleoclimatology 36: e2020PA003934. https://doi.org/10.1029/2020PA003934 DOI: https://doi.org/10.1029/2020PA003934

Bayliss-Smith, T. Constraints on population growth: The case of the Polynesian Outlier Atolls in the precontact period. Hum Ecol 2, 259–295 (1974). https://doi.org/10.1007/BF01531318 DOI: https://doi.org/10.1007/BF01531318

Bellwood, P. S. 1978. Man’s Conquest of the Pacific: the Prehistory of Southeast Asia and Oceania. London: Collins.

Bhattacharya, T., S. Krause, D. Penny, and D. Wahl. 2022. "Drought and water management in ancient Maya society." Progress in Physical Geography: Earth and Environment 47, no. 2: 189–204. https://doi.org/10.1177/03091333221129784 DOI: https://doi.org/10.1177/03091333221129784

Blaauw, M., and J. A. Christen. 2011. "Flexible paleoclimate age-depth models using an autoregressive gamma process." Bayesian Analysis 6: 457–474. https://doi.org/10.1214/11-BA618 DOI: https://doi.org/10.1214/ba/1339616472

Bridgeman, H. A. 1983. "Could climatic change have had an influence on the Polynesian migrations?" Palaeogeography, Palaeoclimatology, Palaeoecology 41: 193–206. DOI: https://doi.org/10.1016/0031-0182(83)90087-1

Brown, J. R., M. Lengaigne, B. R. Lintner, M. J. Widlansky, K. van der Wiel, C. Dutheil, B. K. Linsley, A. J. Matthews, and J. Renwick. 2020. "South Pacific Convergence Zone dynamics, variability and impacts in a changing climate." Nature Reviews Earth & Environment 1: 530–543. https://doi.org/10.1038/s43017-020-0078-2 DOI: https://doi.org/10.1038/s43017-020-0078-2

Carson, M. T. 2024. Archaeology of Pacific Oceania: Inhabiting a Sea of Islands. 2nd ed. London & New York: Routledge. DOI: https://doi.org/10.4324/9781003399025

Cobb, K. M., N. Westphal, H. R. Sayani, J. T. Watson, E. D. Lorenzo, H. Cheng, R. L. Edwards, and C. D. Charles. 2013. "Highly Variable El Niño–Southern Oscillation throughout the Holocene." Science 339: 67–70. https://doi.org/10.1126/science.1228246 DOI: https://doi.org/10.1126/science.1228246

Cochrane, E. E. 2018. "The evolution of migration: the case of Lapita in the southwest Pacific." Journal of Archaeological Method and Theory 25, no. 2: 520–558. https://doi.org/10.1007/s10816-017-9345-z DOI: https://doi.org/10.1007/s10816-017-9345-z

Cochrane, E. E., & Rieth, T. M. 2016. Sāmoan artefact provenance reveals limited artefact transfer within and beyond the archipelago. Archaeology in Oceania, 51, 150–157. https://doi.org/10.1002/arco.5090 DOI: https://doi.org/10.1002/arco.5090

Conroy, J. L., J. T. Overpeck, and J. E. Cole. 2008. "El Niño/Southern Oscillation and changes in the zonal gradient of tropical Pacific sea surface temperature over the last 1.2 ka." PAGES News 18: 32–34. http://pages-142.unibe.ch/products/newsletters/2010-1/Open%20highlights/Conroy_2010-1(32-34).pdf DOI: https://doi.org/10.22498/pages.18.1.32

Cook, B. I., J. E. Smerdon, E. R. Cook, et al. 2022. "Megadroughts in the Common Era and the Anthropocene." Nature Reviews Earth & Environment 3: 741–757. https://doi.org/10.1038/s43017-022-00329-1 DOI: https://doi.org/10.1038/s43017-022-00329-1

d’Aubert, A., and P. D. Nunn. 2012. Furious Winds and Parched Islands: Tropical Cyclones (1558–1970) and Droughts (1722–1987) in the Pacific. United States: Xlibris Corporation.

Dickson, T., H. Farr, D. Sear, and J. I. R. Blake. 2019. "Uncertainty in marine weather routing." Applied Ocean Research 88: 138–146. https://doi.org/10.1016/j.apor.2019.04.008 DOI: https://doi.org/10.1016/j.apor.2019.04.008

Dinapoli, R.J., and Morrison, A.E. 2017. Human behavioural ecology and Pacific archaeology, Archaeology in Oceania, 52: 1–12. https://doi.org/10.1002/arco.5124. DOI: https://doi.org/10.1002/arco.5124

Douglas, P. M. J., A. A. Demarest, M. Brenner, and M. A. Canuto. 2016. "Drought Impacts on the Lowland Maya Civilization." Annual Review of Earth and Planetary Sciences 44: 613–645. https://doi.org/10.1146/annurev-earth-060115-012512 DOI: https://doi.org/10.1146/annurev-earth-060115-012512

Duvat V.K.E, Magnan A.K, Perry C.T, et al. Risks to future atoll habitability from climate-driven environmental changes. WIREs Clim Change. 12:700e. https://doi.org/10.1002/wcc.700 DOI: https://doi.org/10.1002/wcc.700

Evans, N. P., T. K. Bauska, F. Gázquez-Sánchez, M. B. Brenner, J. H. Curtis, and D. A. Hodell. 2018. "Quantification of drought during the collapse of the classic Maya civilization." Science 361: 498–501. https://doi.org/10.1126/science.aas9871 DOI: https://doi.org/10.1126/science.aas9871

Fitzpatrick, S. M. 2010. "A critique of the ‘AD 1300 event’, with particular reference to Palau." Journal of Pacific Archaeology 1, no. 2: 168–173. https://doi.org/10.70460/jpa.v1i2.15 DOI: https://doi.org/10.70460/jpa.v1i2.15

Fujiki, T., K. Sakai, and M. Okuno. 2023. "Reconstruction of vegetation changes on Atiu Island, southern Cook Islands, East Polynesia, based on pollen analysis: Verification of human impacts." The Quaternary Research (Daiyonki-Kenkyu) 62, no. 2: 123–133. https://doi.org/10.4116/jaqua.62.2202 DOI: https://doi.org/10.4116/jaqua.62.2202

Goodwin, I. D., S. A. Browning, and A. J. Anderson. 2014. "Climate windows for Polynesian voyaging to New Zealand and Easter Island." Proceedings of the National Academy of Sciences USA 111: 14716–14721. https://doi.org/10.1073/pnas.1408918111 DOI: https://doi.org/10.1073/pnas.1408918111

Graham, N. E. 2004. "Late-Holocene teleconnections between tropical Pacific climatic variability and precipitation in the western USA: evidence from proxy records." The Holocene 14: 436–447. https://doi.org/10.1191/0959683604hl719xx DOI: https://doi.org/10.1191/0959683604hl719xx

Graves, M. W., and Addison, D. J. 1995. "The Polynesian Settlement of the Hawaiian Archipelago: Integrating Models and Methods in Archaeological Interpretation." World Archaeology 26: 380–399. https://doi.org/10.1080/00438243.1995.9980283. DOI: https://doi.org/10.1080/00438243.1995.9980283

Green, R. C. 2002. "A retrospective view of settlement pattern studies in Samoa." In Pacific Landscapes: Archaeological Approaches, edited by T. Ladefoged and M. Graves, 125–152. The Easter Island Foundation.

Hamilton, B. K., and J. G. Kahn. 2007. "Pre-contact population in ’Opunohu Valley, Mo’orea." In The Growth and Collapse of Pacific Island Societies, edited by P. V. Kirch and R. L. Rallu, 129–159. Honolulu: University of Hawai’i Press. DOI: https://doi.org/10.1515/9780824864767-011

Harris, D. N., M. D. Kessler, A. C. Shetty, D. E. Weeks, R. L. Minster, S. Browning, E. E. Cochrane, R. Deka, N. L. Hawley, M. A. S. Reupena, T. Naseri, S. T. McGarvey, and T. D. O’Connor. 2020. "Evolutionary history of modern Samoans." Proceedings of the National Academy of Sciences 117, no. 23: 13157. https://doi.org/10.1073/pnas.1913157117 DOI: https://doi.org/10.1073/pnas.1913157117

Hernández, A., C. Martin-Puertas, P. Moffa-Sánchez, E. Moreno-Chamarro, P. Ortega, S. Blockley, K. M. Cobb, L. Comas-Bru, S. Giralt, H. Goosse, J. Luterbacher, B. Martrat, R. Muscheler, A. Parnell, S. Pla-Rabes, J. Sjolte, A. A. Scaife, D. Swingedouw, E. Wise, and C. Xu. 2020. "Modes of climate variability: Synthesis and review of proxy-based reconstructions through the Holocene." Earth-Science Reviews 209: 103286. https://doi.org/10.1016/j.earscirev.2020.103286 DOI: https://doi.org/10.1016/j.earscirev.2020.103286

Hipkiss, C. V., J. Sheffield, P. G. Langdon, and D. A. Sear. 2025. "Modelling the impact of large-scale hydroclimate change on prehistoric Polynesian island life." Quaternary Environments and Humans 3, no. 2: 100074. https://doi.org/10.1016/j.qeh.2025.100074 DOI: https://doi.org/10.1016/j.qeh.2025.100074

Hostetler, S. W. , Benson, L. V. , 1994. Stable isotopes of oxygen and hydrogen in the Truckee River–Pyramid Lake surface-water system. 2. A predictive model of δ18O and δ2H in Pyramid Lake, Limnology and Oceanography, 39, doi: https://doi.org/10.4319/lo.1994.39.2.0356 DOI: https://doi.org/10.4319/lo.1994.39.2.0356

Hudjashov, G., P. Endicott, H. Post, N. Nagle, S. Y. W. Ho, D. J. Lawson, M. Reidla, M. Karmin, S. Rootsi, E. Metspalu, L. Saag, R. Villems, M. P. Cox, R. J. Mitchell, R. L. Garcia-Bertrand, M. Metspalu, and R. J. Herrera. 2018. "Investigating the origins of eastern Polynesians using genome-wide data from the Leeward Society Isles." Scientific Reports 8, no. 1: 1823. https://doi.org/10.1038/s41598-018-20026-8 DOI: https://doi.org/10.1038/s41598-018-20026-8

Iese, V., A. S. Kiem, A. Mariner, P. Malsale, T. Tofaeono, D. G. C. Kirono, V. Round, C. Heady, R. Tigona, F. Vesia, K. Posanau, F. Aiono, A. Haruhiru, A. Daphne, V. Vainikolo, and N. Iona. 2021. "Historical and future drought impacts in the Pacific islands and atolls." Climatic Change 166: 19. https://doi.org/10.1007/s10584-021-03112-1 DOI: https://doi.org/10.1007/s10584-021-03112-1

Irwin, G. 1992. The Prehistoric Exploration and Colonisation of the Pacific. Cambridge: Cambridge University Press. DOI: https://doi.org/10.1017/CBO9780511518225

Irwin, G. 1998. "The colonisation of the Pacific Plate: chronological, navigational and social issues." Journal of the Polynesian Society 107: 111–43.

Irwin, G., R. G. J. Flay, L. Dudley, and D. Johns. 2023. "The sailing performance of ancient Polynesian canoes and the early settlement of East Polynesia." Archaeology in Oceania 58: 74–90. https://doi.org/10.1002/arco.5277 DOI: https://doi.org/10.1002/arco.5277

Irwin, G., R. G. J. Flay, L. Dudley, and D. Johns. 2024. "The sailing performance of ancient Pacific canoes: Technological innovations and migrations." In The Oxford Handbook of Island and Coastal Archaeology, edited by S. M. Fitzpatrick and J. Erlandson. New York: Oxford University Press. DOI: https://doi.org/10.1093/oxfordhb/9780197607770.013.4

Jiang, S., X. Zhou, J. P. Sachs, Z. Li, L. Tu, Y. Lin, X. Liu, A. Chen, and Y. Shen. 2023. "The mean state of the tropical Pacific Ocean differed between the Medieval Warm Period and the Industrial Era." Communications Earth & Environment 4: 106. https://doi.org/10.1038/s43247-023-00777-7 DOI: https://doi.org/10.1038/s43247-023-00734-4

Kirch, P. V. 1984. The Evolution of the Polynesian Chiefdoms. Cambridge: Cambridge University Press.

Kirch, P. V. 1994. The Wet and the Dry: Irrigation and Agricultural Intensification in Polynesia. London: The University of Chicago Press.

Kirch, P. V. 2017. Tangatatau Rockshelter: The Evolution of an Eastern Polynesian Socio-ecosystem. Monumenta Archaeologica 40. Los Angeles: Cotsen Institute of Archaeology Press. DOI: https://doi.org/10.2307/j.ctvdmwx40

Kirch, P. V. 2020a. On the Road of the Winds: An Archaeological History of the Pacific Islands before European Contact. Berkeley: University of California Press.

Kirch, P. V. 2020b. "Controlled Comparison and Polynesian Cultural Evolution." In Theory in the Pacific, the Pacific in Theory: Archaeological Perspectives, edited by T. Thomas, 79–101. Abingdon: Routledge. DOI: https://doi.org/10.4324/9780203730973-4

Kirch, P. V., J. Holson, and A. Baer. 2009. "Intensive Dryland Agriculture in Kaupō, Maui, Hawaiian Islands." Asian Perspectives 48: 265–290. DOI: https://doi.org/10.1353/asi.2009.0006

Kirch, P. V., and R. Green. 2001. Hawaiki: Ancestral Polynesia. An essay in Historical Anthropology. Cambridge: Cambridge University Press. DOI: https://doi.org/10.1017/CBO9780511613678

Kuil, L., G. Carr, A. Viglione, A. Prskawetz, and G. Blöschl. 2016. "Conceptualizing socio-hydrological drought processes: The case of the Maya collapse." Water Resources Research 52: 6222–6242. https://doi.org/10.1002/2015WR018298 DOI: https://doi.org/10.1002/2015WR018298

Kuil, L., G. Carr, A. Prskawetz, J. L. Salinas, A. Viglione, and G. Blöschl. 2019. "Learning from the Ancient Maya: Exploring the Impact of Drought on Population Dynamics." Ecological Economics 157: 1–16. https://doi.org/10.1016/j.ecolecon.2018.10.018. DOI: https://doi.org/10.1016/j.ecolecon.2018.10.018

Ladd, S. N., A. E. Maloney, D. B. Nelson, M. Prebble, G. Camperio, D. A. Sear, J. D. Hassall, P. G. Langdon, J. P. Sachs, and N. Dubois. 2021. "Leaf wax hydrogen isotopes as a hydroclimate proxy in the tropical Pacific." Journal of Geophysical Research: Biogeosciences 126, no. 3: e2020JG005891. https://doi.org/10.1029/2020JG005891 DOI: https://doi.org/10.1029/2020JG005891

Ladefoged, T. N., and M. W. Graves. 2008. "Variable Development of Dryland Agriculture in Hawai‘i: A Fine-Grained Chronology from the Kohala Field System, Hawai‘I Island." Current Anthropology 49: 771–802. https://doi.org/10.1086/591424 DOI: https://doi.org/10.1086/591424

Leppard, T. P., E. E. Cochrane, D. Gaffney, C. L. Hofman, J. E. Laffoon, M. M. E. Bunbury, and C. Broodbank. 2022. "Global Patterns in Island Colonization during the Holocene." Journal of World Prehistory 35: 163–232. https://doi.org/10.1007/s10963-022-09168-w DOI: https://doi.org/10.1007/s10963-022-09168-w

Lipson, M., P. Skoglund, M. Spriggs, F. Valentin, S. Bedford, R. Shing, H. Buckley, I. Phillip, G. K. Ward, S. Mallick, N. Rohland, N. Broomandkhoshbacht, O. Cheronet, M. Ferry, T. K. Harper, M. Michel, J. Oppenheimer, K. Sirak, K. Stewardson, and D. Reich. 2018. "Population turnover in remote oceania shortly after initial settlement." Current Biology 28, no. 1: R183–R189. https://doi.org/10.1016/j.cub.2018.02.051 DOI: https://doi.org/10.1101/268037

Lima M., Gayo E. M., Latorre, C., Santoro, C.M., Estay, A., Cañellas-Boltà, N., Margalef, O., Giralt, S., Sáez, A., Pla-Rabes, S., Chr. Stenseth, N., 2020. Ecology of the collapse of Rapa Nui society. Proc. R. Soc. B 287: 20200662. http://dx.doi.org/10.1098/rspb.2020.0662 DOI: https://doi.org/10.1098/rspb.2020.0662

Maloney, A. E., D. B. Nelson, J. N. Richey, M. Prebble, D. A. Sear, J. D. Hassall, P. G. Langdon, I. W. Croudace, A. Zawadzki, and J. P. Sachs. 2019. "Reconstructing precipitation in the tropical South Pacific from dinosterol $delta^{2}H$ ratios in lake sediment." Geochimica et Cosmochimica Acta 245: 190–206. https://doi.org/10.1016/j.gca.2018.10.028 DOI: https://doi.org/10.1016/j.gca.2018.10.028

Maloney, A. E., J. N. Richey, D. B. Nelson, S. N. Hing, D. A. Sear, J. D. Hassall, P. G. Langdon, U. Sichrowsky, R. Schabetsberger, A. Malau, and J. Y. Meyer. 2022. "Contrasting Common Era climate and hydrology sensitivities from paired lake sediment dinosterol hydrogen isotope records in the South Pacific Convergence Zone." Quaternary Science Reviews 281: 107421. https://doi.org/10.1016/j.quascirev.2022.107421 DOI: https://doi.org/10.1016/j.quascirev.2022.107421

Manning, S. W., C. Kocik, B. Lorentzen, et al. 2023. "Severe multi-year drought coincident with Hittite collapse around 1198–1196 BC." Nature 614: 719–724. https://doi.org/10.1038/s41586-022-05693-y DOI: https://doi.org/10.1038/s41586-022-05693-y

Martinez-Dyrzo, H. B. 2024. "Spatial and temporal distribution of palaeoclimatic records in the Maya Area." Revista Mexicana de Ciencias Geológicas 41, no. 1: 27–52. https://doi.org/10.22201/cgeo.20072902e.2024.1.1751. DOI: https://doi.org/10.22201/cgeo.20072902e.2024.1.1751

Matthews, A. J., B. J. Hoskins, J. M. Slingo, and M. Blackburn. 1996. "Development of convection along the SPCZ within a Madden-Julian oscillation." Quarterly Journal of the Royal Meteorological Society 122: 669–688. https://doi.org/10.1002/qj.49712253106 DOI: https://doi.org/10.1256/smsqj.53105

Matisoo-Smith, E., and A. L. Gosling. 2025. "Understanding the human settlement of the Pacific – Are we there yet?" Journal of Archaeological Science 180: 106307. https://doi.org/10.1016/j.jas.2025 DOI: https://doi.org/10.1016/j.jas.2025.106307

McGee, D., Quade, J., Edwards, R.L., Broecker, W.S., Cheng, H., Reiners, P.W., Evenson, N. 2012. Lacustrine cave carbonates: Novel archives of paleohydrologic change in the Bonneville Basin (Utah, USA), Earth and Planetary Science Letters, 351–352,182-194. https://doi.org/10.1016/j.epsl.2012.07.019 DOI: https://doi.org/10.1016/j.epsl.2012.07.019

Menking, K.M., Bischoff, J.L., Fitzpatrick, J.A., Burdette, J.W., Rye, R.O. 1997. Climatic/Hydrologic Oscillations since 155,000 yr B.P. at Owens Lake, California, Reflected in Abundance and Stable Isotope Composition of Sediment Carbonate. Quaternary Research.48, 1:58-68. https://doi.org/10.1006/qres.1997.1898 DOI: https://doi.org/10.1006/qres.1997.1898

Molle, G., and E. Conte. 2015. "Nuancing the Marquesan Post-contact Demographic Decline: An Archaeological and Historical Case Study on Ua Huka Island." Journal of Pacific History 50, no. 3: 253–274. https://doi.org/10.1080/00223344.2015.1078065 DOI: https://doi.org/10.1080/00223344.2015.1078065

Moy, C. M., G. O. Seltzer, D. T. Rodbell, and D. M. Anderson. 2002. "Variability of El Niño/Southern Oscillation activity at millennial timescales during the Holocene epoch." Nature 420: 162–165. https://doi.org/10.1038/nature01194 DOI: https://doi.org/10.1038/nature01194

Mulrooney, M. A., S. H. Bickler, M. S. Allen, and T. N. Ladefoged. 2011. "High-precision dating of colonization and settlement in East Polynesia." Proceedings of the National Academy of Sciences USA 108: E192–194; author reply E195. https://doi.org/10.1073/pnas.1105499108. DOI: https://doi.org/10.1073/pnas.1100447108

Niespolo, E. M., W. D. Sharp, and P. V. Kirch. 2019. "U/Th dating of coral abraders from stratified deposits at Tangatatau Rockshelter, Mangaia, Cook Islands: Implications for building precise chronologies in Polynesia." Journal of Archaeological Science 101: 21–33. https://doi.org/10.1016/j.jas.2018.11.001 DOI: https://doi.org/10.1016/j.jas.2018.11.001

Nogué, S., A. M. Santos, H. J. B. Birks, S. Björck, A. Castilla-Beltrán, S. Connor, M. J. Steinbauer, and J. M. Wilmshurst. 2021. "The human dimension of biodiversity changes on islands." Science 372, no. 6541: 488–491. https://doi.org/10.1126/science.abd6706 DOI: https://doi.org/10.1126/science.abd6706

Nunn, P. D. 2000. "Environmental catastrophe in the Pacific islands around A.D. 1300." Geoarchaeology 15: 715–740. https://doi.org/10.1002/1520-6548(200010)15:7<715::AID-GEA4>3.0.CO;2-L DOI: https://doi.org/10.1002/1520-6548(200010)15:7<715::AID-GEA4>3.0.CO;2-L

Nunn, P. D. 2007. Climate, environment and society in the Pacific during the last millennium. Amsterdam: Elsevier.

Nunn, P.D. and Britton, J.M.R. 2001. Human-environment relationships in the Pacific around A.D. 1300. Environment & History, 7, 1; 3-22. DOI: https://doi.org/10.3197/096734001129342388

Nunn, P. D., Kumar, L., Eliot, I. 2016. Classifying Pacific islands. Geoscience Letter. 3, 7. https://doi.org/10.1186/s40562-016-0041-8 DOI: https://doi.org/10.1186/s40562-016-0041-8

Parton, P., and G. Clark. 2022. "Using lidar and Bayesian inference to reconstruct archaeological populations in the Kingdom of Tonga." Journal of Archaeological Science: Reports 45: 103610. https://doi.org/10.1016/j.jasrep.2022.103610 DOI: https://doi.org/10.1016/j.jasrep.2022.103610

Peaple, M., D. T. Skinner, G. N. Inglis, M. Joshi, P. G. Langdon, A. J. Matthews, T. Osborn, and D. A. Sear. 2025. "Ocean variability drives a millennial-scale shift in South Pacific hydroclimate." Communications Earth & Environment 6: 679. https://doi.org/10.1038/s43247-025-02676-5 DOI: https://doi.org/10.1038/s43247-025-02676-5

Pérez-Pereira, N., Wang, J., Quesada, H. Cabellero, A. 2022. Prediction of the minimum effective size of a population viable in the long term. Biodivers Conserv 31, 2763–2780. https://doi.org/10.1007/s10531-022-02456-z DOI: https://doi.org/10.1007/s10531-022-02456-z

Posth, C., K. Nägele, H. Colleran, F. Valentin, S. Bedford, K.W. Kami, R. Shing, et al., 2018. Language continuity despite population replacement in Remote Oceania. Nature Ecology & Evolution 2 (4): 731–40.Power, S., T. Casey, C. Folland, A. Colman, and V. Mehta. 1999. "Inter-decadal modulation of the impact of ENSO on Australia." Climate Dynamics 15: 319–324. https://doi.org/10.1038/s41559-018-0498-2 DOI: https://doi.org/10.1007/s003820050284

Puleston, C. O., J. G. Kahn, O. A. Chadwick, et al. 2024. "People of the Sea, or of the Soil? How the Balance of Marine and Terrestrial Resource Availability Informs Maximum Population on Four Polynesian Islands." Human Ecology 52: 713–729. https://doi.org/10.1007/s10745-024-00530-4 DOI: https://doi.org/10.1007/s10745-024-00530-4

Rallu J-L. 2022.Patterns of population decline following European contact and colonization: The cases of Tahiti and the Marquesas Population and Economics 6(2): 88–107, https://doi.org/10.3897/popecon.6.e81900 DOI: https://doi.org/10.3897/popecon.6.e81900

Rallu J-L. 2023. Rarotonga Population from Contact to the 1880s. Pacific Populations, Fertility, Mortality and Movement in Colonial Oceania, UNSW, Jun 2023, Sydney (AUSTRALIA), Australia. hal-04354860.

Rallu J-L. 2024. Tahiti Population (Re)Estimates and Ideologies. Population and Economics 8(2):231-262. https://doi.org/10.3897/popecon.8.e11682 DOI: https://doi.org/10.3897/popecon.8.e116822

Rasmussen, K., W. May, T. Birk, M. Mataki, O. Mertz, and D. Yee. 2009. "Climate change on three Polynesian outliers in the Solomon Islands: Impacts, vulnerability and adaptation." Geografisk Tidsskrift-Danish Journal of Geography 109: 1–13. https://doi.org/10.1080/00167223.2009.10649592 DOI: https://doi.org/10.1080/00167223.2009.10649592

Romanek, C.S., Grossman, E.L., Morse, J.W. 1992. Carbon isotopic fractionation in synthetic aragonite and calcite: Effects of temperature and precipitation rate, Geochimica et Cosmochimica Acta, 56,1, 419-430, https://doi.org/10.1016/0016-7037(92)90142-6 DOI: https://doi.org/10.1016/0016-7037(92)90142-6

Rull, V., and C. Stevenson. 2022. "Towards a Holistic Approach to Easter Island’s Prehistory." In The Prehistory of Rapa Nui (Easter Island), edited by V. Rull and C. Stevenson, Developments in Paleoenvironmental Research 22. Cham: Springer. https://doi.org/10.1007/978-3-030-91127-0_24 DOI: https://doi.org/10.1007/978-3-030-91127-0

Sachse, D., I. Billault, G. J. Bowen, Y. Chikaraishi, T. E. Dawson, S. J. Feakins, et al. 2012. "Molecular paleohydrology: interpreting the hydrogen-isotopic composition of lipid biomarkers from photosynthesizing organisms." Annual Review of Earth and Planetary Sciences 40, no. 1: 221–249. https://doi.org/10.1146/annurev-earth-042711-105535 DOI: https://doi.org/10.1146/annurev-earth-042711-105535

Schmid, M. M. E., A. J. Dugmore, L. Foresta, A. J. Newton, O. Vésteinsson, and R. Wood. 2018. "How 14C dates on wood charcoal increase precision when dating colonization: The examples of Iceland and Polynesia." Quaternary Geochronology 48: 64–71. https://doi.org/10.1016/j.quageo.2018.07.015 DOI: https://doi.org/10.1016/j.quageo.2018.07.015

Sear, D. A., M. S. Allen, J. D. Hassall, A. E. Maloney, P. G. Langdon, A. E. Morrison, A. C. G. Henderson, H. Mackay, I. W. Croudace, C. Clarke, J. P. Sachs, G. Macdonald, R. C. Chiverrell, M. J. Leng, L. M. Cisneros-Dozal, T. Fonville, and E. Pearson. 2020. "Human settlement of East Polynesia earlier, incremental, and coincident with prolonged South Pacific drought." Proceedings of the National Academy of Sciences 117: 8813–8819. https://doi.org/10.1073/pnas.1920975117 DOI: https://doi.org/10.1073/pnas.1920975117

Sheppard, P.J. 2022. Southeast Solomon Islands in regional perspective: Settlement history, interaction spheres, Polynesian outliers and Eastward dispersals. Journal of the Polynesian Society 131 (2): 113–184. https://doi.org/10.15286/jps.131.2.113-184 DOI: https://doi.org/10.15286/jps.131.2.113-184

Steiger, N., Smerdon, J., Cook, E., Cook , B.I. 2018. A reconstruction of global hydroclimate and dynamical variables over the Common Era. Sci Data 5, 180086. https://doi.org/10.1038/sdata.2018.86 DOI: https://doi.org/10.1038/sdata.2018.86

Strandberg, N. A., M. J. Steinbauer, A. Walentowitz, W. D. Gosling, P. L. Fall, M. Prebble, J. Stevenson, J. M. Wilmshurst, D. A. Sear, P. G. Langdon, M. E. Edwards, and S. Nogué. 2024. "Floristic homogenization of South Pacific islands commenced with human arrival." Nature Ecology & Evolution 8: 382–391. https://doi.org/10.1038/s41559-023-02306-3 DOI: https://doi.org/10.1038/s41559-023-02306-3

Swart, P.K. 2015. The geochemistry of carbonate diagenesis: The past, present and future. Sedimentology, 62: 1233-1304. https://doi.org/10.1111/sed.12205 DOI: https://doi.org/10.1111/sed.12205

Tomlinson, S., Lomolino, M.V., Anderson, A., Sean Tomlinson, Austin, J., Brown, A. C. Haythorne, S., Perry, G.L.W., Wilmshurst, J.M., Wood, J.R. and Fordham, D.A. 2024. Reconstructing colonization dynamics to establish how human activities transformed island biodiversity. Sci Rep 14, 5261. https://doi.org/10.1038/s41598-024-55180-9 DOI: https://doi.org/10.1038/s41598-024-55180-9

Thomas, T. 2020. "Pacific colonisation as process and practice." In Theory in the Pacific, the Pacific in Theory: Archaeological Perspectives, edited by T. Thomas, 35–56. Abingdon: Routledge. https://doi.org/10.4324/9780203730973 DOI: https://doi.org/10.4324/9780203730973-7

Ulus, T., and R. Ellenblum. 2021. "How long and how strong must a climatic anomaly be in order to evoke a social transformation? Historical and contemporaneous case studies." Humanities and Social Sciences Communications 8: 252. https://doi.org/10.1057/s41599-021-00933-4 DOI: https://doi.org/10.1057/s41599-021-00933-4

University of the South Pacific. 1984. Atiu nui maruarua: e au tua ta'ito. Suva, Fiji: Institute of Pacific Studies of the University of the South Pacific.

van der Wiel, K., A. J. Matthews, M. M. Joshi, and D. P. Stevens. 2016. "Why the South Pacific convergence zone is diagonal." Climate Dynamics 46: 1683–1698. https://doi.org/10.1007/s00382-015-2668-0 DOI: https://doi.org/10.1007/s00382-015-2668-0

Weisler, M. I. 1996. "Taking the mystery out of the Polynesian ‘mystery islands’: a case study from Mangareva and the Pitcairn Group." In Oceanic Culture History: Essays in Honour of Roger Green, edited by J. M. Davidson, G. Irwin, B. F. Leach, A. Pawley, and D. Brown, 615–629. New Zealand Journal of Archaeology Special Publication.

Wilson, W. H. 2012. "Whence the east Polynesians? Further linguistic evidence for a Northern outlier source." Oceanic Linguistics 51, no. 2: 289–359. https://doi.org/10.2307/3623064 DOI: https://doi.org/10.1353/ol.2012.0014

Wilson, W. H. 2018. "The Northern Outliers-East Polynesian hypothesis expanded." Journal of the Polynesian Society 127, no. 4: 389–432. https://doi.org/10.15286/jps.127 DOI: https://doi.org/10.15286/jps.127.4.389-423

Wilson, W.H. 2021. East Polynesian subgrouping and homeland implications within the Northern Outlier–East Polynesian hypothesis. Oceanic Linguistics 60 (1): 36–71. https://doi.org/10.1353/ol.2021.0001 DOI: https://doi.org/10.1353/ol.2021.0001