Polynesia

Polynesia is a subregion of Oceania, made up of more than 1,000 islands scattered over the central and southern Pacific Ocean. The indigenous people who inhabit the islands of Polynesia are called Polynesians. They have many things in common, including linguistic relations, cultural practices, and traditional beliefs.
The term Polynésie was first used in 1756 by the French writer Charles de Brosses, who originally applied it to all the islands of the Pacific. In 1831, Jules Dumont d'Urville proposed a narrower definition during a lecture at the Société de Géographie of Paris. By tradition, the islands located in the southern Pacific have also often been called the South Sea Islands, and their inhabitants have been called South Sea Islanders. The Hawaiian Islands have often been considered to be part of the South Sea Islands because of their relative proximity to the southern Pacific islands, even though they are in fact located in the North Pacific. Another term in use, which avoids this inconsistency, is "the Polynesian Triangle". This term makes clear that the grouping includes the Hawaiian Islands, which are located at the northern vertex of the referenced "triangle".

Geography

Geology

Polynesia is characterized by a small amount of land spread over a very large portion of the mid- and southern Pacific Ocean. It comprises approximately of land, of which more than are within New Zealand. The Hawaiian archipelago comprises about half the remainder.
Most Polynesian islands and archipelagos, including the Hawaiian Islands and Samoa, are composed of volcanic islands built by hotspots. The other land masses in Polynesia — New Zealand, Norfolk Island, and Ouvéa, the Polynesian outlier near New Caledonia — are the unsubmerged portions of the largely sunken continent of Zealandia.
Zealandia is believed to have mostly sunk below sea level 23 million years ago, and recently partially resurfaced due to a change in the movements of the Pacific Plate in relation to the Indo-Australian Plate. The Pacific plate had previously been subducted under the Australian Plate. When that changed, it had the effect of uplifting the portion of the continent that is modern-day New Zealand.
The convergent plate boundary that runs northwards from New Zealand's North Island is called the Kermadec-Tonga subduction zone. This subduction zone is associated with the volcanism that gave rise to the Kermadec and Tongan islands.
There is a transform fault that currently traverses New Zealand's South Island, known as the Alpine Fault.
Zealandia's continental shelf has a total area of approximately.
The oldest rocks in Polynesia are found in New Zealand and are believed to be about 510 million years old. The oldest Polynesian rocks outside Zealandia are to be found in the Hawaiian Emperor Seamount Chain and are 80 million years old.

Geographical area

Polynesia is generally defined as the islands within the Polynesian Triangle, although some islands inhabited by Polynesians are situated outside that area. Geographically, the Polynesian Triangle is drawn by connecting the points of Hawaii, New Zealand, and Easter Island. The other main island groups located within the Polynesian Triangle are Samoa, Tonga, the Cook Islands, Tuvalu, Tokelau, Niue, Wallis and Futuna, and French Polynesia.
Also, small Polynesian settlements are in Papua New Guinea, the Solomon Islands, the Caroline Islands, and Vanuatu. An island group with strong Polynesian cultural traits outside of this great triangle is Rotuma, situated north of Fiji. The people of Rotuma have many common Polynesian traits, but speak a non-Polynesian language. Some of the Lau Islands to the southeast of Fiji have strong historic and cultural links with Tonga. However, in essence, Polynesia remains a cultural term referring to one of the three parts of Oceania.

Island groups

The following islands and island groups are either nations or overseas territories of former colonial powers. The residents are native Polynesians or contain archaeological evidence indicating Polynesian settlement in the past. Some islands of Polynesian origin are outside the general triangle that geographically defines the region.

Polynesian area

The Line Islands and the Phoenix Islands, most of which are parts of Kiribati, had no permanent settlements until European colonization, but are often considered to be parts of the Polynesian Triangle.
Polynesians once inhabited the Auckland Islands, the Kermadec Islands, and Norfolk Island in pre-colonial times, but these islands were uninhabited by the time European explorers arrived.
The oceanic islands to the east of Easter Island, such as Clipperton Island, the Galápagos Islands, and the Juan Fernández Islands, were in the past formerly categorized on rare occasion as part of Polynesia. No evidence of prehistoric contact with either Polynesians or the indigenous peoples of the Americas has been found.

Outliers

Melanesia

Origins and expansion

The Polynesian people are considered, by linguistic, archaeological, and human genetic evidence, a subset of the sea-migrating Austronesian people. Tracing Polynesian languages places their prehistoric origins in Island Melanesia, Maritime Southeast Asia, and ultimately, in Taiwan.
Between about 3000 and 1000 BC, speakers of Austronesian languages spread from Taiwan into Maritime Southeast Asia.
There are three theories regarding the spread of humans across the Pacific to Polynesia. These are outlined well by Kayser et al. and are as follows:

Express Train model: A recent expansion out of Taiwan, via the Philippines and eastern Indonesia and from the northwest of New Guinea, on to Island Melanesia by roughly 1400 BC, reaching western Polynesian islands around 900 BC followed by a roughly 1000 year "pause" before continued settlement in central and eastern Polynesia. This theory is supported by the majority of current genetic, linguistic, and archaeological data.
Entangled Bank model: Emphasizes the long history of Austronesian speakers' cultural and genetic interactions with indigenous Island Southeast Asians and Melanesians along the way to becoming the first Polynesians.
Slow Boat model: Similar to the express-train model but with a longer hiatus in Melanesia along with admixture — genetically, culturally and linguistically — with the local population. This is supported by the Y-chromosome data of Kayser et al., which shows that all three haplotypes of Polynesian Y chromosomes can be traced back to Melanesia.

In the archaeological record, there are well-defined traces of this expansion which allow the path it took to be followed and dated with some certainty. It is thought that by roughly 1400 BC, "Lapita peoples", so-named after their pottery tradition, appeared in the Bismarck Archipelago of northwest Melanesia. This culture is seen as having adapted and evolved through time and space since its emergence "Out of Taiwan". They had given up rice production, for instance, which required paddy field agriculture unsuitable for small islands. However, they still cultivated other ancestral Austronesian staple cultigens like Dioscorea yams and taro, as well as adopting new ones like breadfruit and sweet potato.
File:Chronological dispersal of Austronesian people across the Pacific.svg|upright=2|left|thumb|Map showing the migration and expansion of the Austronesians which began at about 3000 BC from Taiwan. The Polynesian branch is shown in green.
The results of research at the Teouma Lapita site and the Talasiu Lapita site published in 2016 supports the Express Train model; although with the qualification that the migration bypassed New Guinea and Island Melanesia. The conclusion from research published in 2016 is that the initial population of those two sites appears to come directly from Taiwan or the northern Philippines and did not mix with the 'Australo-Papuans' of New Guinea and the Solomon Islands. The preliminary analysis of skulls found at the Teouma and Talasiu Lapita sites is that they lack Australian or Papuan affinities and instead have affinities to mainland Asian populations.
A 2017 DNA analysis of modern Polynesians indicates that there has been intermarriage resulting in a mixed Austronesian-Papuan ancestry of the Polynesians. Research at the Teouma and Talasiu Lapita sites implies that the migration and intermarriage, which resulted in the mixed Austronesian-Papuan ancestry of the Polynesians, occurred after the first initial migration to Vanuatu and Tonga.
A complete mtDNA and genome-wide SNP comparison of the remains of early settlers of the Mariana Islands and early Lapita individuals from Vanuatu and Tonga also suggest that both migrations originated directly from the same ancient Austronesian source population from the Philippines. The complete absence of "Papuan" admixture in the early samples indicates that these early voyages bypassed eastern Indonesia and the rest of New Guinea. The authors have also suggested a possibility that the early Lapita Austronesians were direct descendants of the early colonists of the Marianas, which is also supported by pottery evidence.
The most eastern site for Lapita archaeological remains recovered so far is at Mulifanua on Upolu. The Mulifanua site, where 4,288 pottery shards have been found and studied, has a "true" age of based on radiocarbon dating and is the oldest site yet discovered in Polynesia. This is mirrored by a 2010 study also placing the beginning of the human archaeological sequences of Polynesia in Tonga at 900 BC.
Within a mere three or four centuries, between 1300 and 900 BC, the Lapita archaeological culture spread 6,000 km further to the east from the Bismarck Archipelago, until reaching as far as Fiji, Tonga, and Samoa. A cultural divide began to develop between Fiji to the west, and the distinctive Polynesian language and culture emerging on Tonga and Samoa to the east. Where there was once faint evidence of uniquely shared developments in Fijian and Polynesian speech, most of this is now called "borrowing" and is thought to have occurred in those and later years more than as a result of continuing unity of their earliest dialects on those far-flung lands. Contacts were mediated especially through the Tovata confederacy of Fiji. This is where most Fijian-Polynesian linguistic interactions occurred.
In the chronology of the exploration and first populating of Polynesia, there is a gap commonly referred to as the long pause between the first populating of Fiji, Western Polynesia of Tonga and Samoa among others and the settlement of the rest of the region. In general this gap is considered to have lasted roughly 1,000 years. The cause of this gap in voyaging is contentious among archaeologists with a number of competing theories presented including climate shifts, the need for the development of new voyaging techniques, and cultural shifts.
After the long pause, dispersion of populations into central and eastern Polynesia began. Although the exact timing of when each island group was settled is debated, it is widely accepted that the island groups in the geographic center of the region were settled initially between 1000 and 1150 AD, and ending with more far-flung island groups such as Hawaii, New Zealand, and Easter Island settled between 1200 and 1300 AD.
Tiny populations may have been involved in the initial settlement of individual islands; although Professor Matisoo-Smith of the Otago study said that the founding Māori population of New Zealand must have been in the hundreds, much larger than previously thought. The Polynesian population experienced a founder effect and genetic drift. The Polynesian may be distinctively different both genotypically and phenotypically from the parent population from which it is derived. This is due to new population being established by a very small number of individuals from a larger population which also causes a loss of genetic variation.
Atholl Anderson wrote that analysis of mitochondrial DNA and Y chromosome concluded that the ancestors of Polynesian women were Austronesians while those of Polynesian men were Papuans. Subsequently, it was found that 96% of Polynesian mtDNA has an Asian origin, as does one-third of Polynesian Y chromosomes; the remaining two-thirds from New Guinea and nearby islands; this is consistent with matrilocal residence patterns. Polynesians existed from the intermixing of few ancient Austronesian-Melanesian founders, genetically they belong almost entirely to the Haplogroup B, which is the marker of Austronesian expansions. The high frequencies of mtDNA Haplogroup B in the Polynesians are the result of founder effect and represents the descendants of a few Austronesian females who intermixed with Papuan males.
A genomic analysis of modern populations in Polynesia, published in 2021, provides a model of the direction and timing of Polynesian migrations from Samoa to the islands to the east. This model presents consistencies and inconsistencies with models of Polynesian migration that are based on archaeology and linguistic analysis. The 2021 genomic model presents a migration pathway from Samoa to the Cook Islands, then to the Society Islands in the 11th century AD, the western Austral Islands and the Tuāmotu Archipelago in the 12th century AD, with the migrant pathway branching to the north to the Marquesas, to Raivavae in the south, and to the easternmost destination on Easter Island, which was settled in approximately 1200 AD via Mangareva.