Climate at the time of the Human settlement of the Eastern Pacific

Dr Richard Pearce, David Sear, Pete Langdon, Paul Hughes, SOGES

The migration into the Pacific Ocean and the settlement of island archipelagoes by the ancestors of modern Pacific islanders is contested yet remains one of humankinds greatest achievements. Evidence for when and why people chose to undertake hazardous voyages is uncertain, but recent hypotheses developed in part by the supervisory team, point to a coincidence with a widespread regional drought (Sear et al. 2020; Maloney et al. 2022). What we are less certain of is what role climate played in driving the migrations east into Polynesia and how it supported those migrations – were they in effect “chasing the rain” east as drought developed in the west?  What is also unclear is the extent of this drought and the detail of its duration around the eastern region settled by the Polynesian voyagers. To understand this requires robust dated sediment archives containing both unequivocal evidence for human arrival and presence, and hydroclimate proxies. This project will develop these for 3 islands in French Polynesia and combine the new records with existing evidence from other regions of the Pacific (e.g. Cook Is., Marquesas Is. e.g. Allen et al. 2011) to understand the temporal and spatial coincidence of climate and human migration.



This project will analyse a swamp sediment archive collected in the NERC PROMS (Pacific Rainfall over millennial scales) Research project, from 3 sites across French Polynesia, that date back beyond the arrival of humans c.800-1000 A.D. The successful candidate will use a range of techniques to derive new proxy records for both climate (e.g. Stable isotopes, a new testate amoebae transfer functions) and human presence (faecal indicators of pigs and / or humans, geochemical and macrofossil evidence for human disturbance to natural ecosystems). Geochronology will be constrained using radiocarbon and cryptotephra (volcanic eruption airborne ash) – the latter building off our newly emerging pacific tephra framework, with the opportunity for the student to work with Dr Anna Bourne at QMUL. Geospatial data analysis will enable the candidate to assimilate the new information into wider paleoclimate and human settlement datasets, allowing for the first time, reconstruction of regional trends in climate and human migration into the Pacific.

University of Southampton, SOGES

The INSPIRE DTP programme provides comprehensive personal and professional development training alongside extensive opportunities for students to expand their multi-disciplinary outlook through interactions with a wide network of academic, research and industrial/policy partners. The student will be registered at the University of Southampton and hosted at School of Geography & Environmental Science. Specific training may depending on need, include:

SEM analyses (SOES)

Palaeolimnological, palaeoecological and sedimentological analyses (SOGES)

Biomarker analyses (SOES/SOGES)

Tephra and radiocarbon chronology (SOGES/QMUL).

Time series and geospatial analysis of palaeoenvironmental data, (SOGES).
The student will be encouraged to participate in Quaternary Research Association meetings and training, alongside relevant UKRI and internal training. The student will also benefit from participation in the wider NERC PROMS team. There may be an opportunity to spend time in New Zealand at the Dept. of Anthropology, University of Auckland.


Eligibility & Funding Details: 

Please see for details.


Background Reading: 

Sear et al. (2020). Human settlement of East Polynesia earlier, incremental, and coincident with prolonged South Pacific drought. PNAS 117: 8813-8819.

Maloney, A.E. et al. (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.

Allen, M.S. et al. (2011). New pollen, sedimentary, and radiocarbon records from the Marquesas Islands, East Polynesia: implications for archaeological and palaeoclimate studies. The Holocene, 21: 473-484