scholarly journals Population Turnover in Remote Oceania Shortly After Initial Settlement

2018 ◽  
Author(s):  
Mark Lipson ◽  
Pontus Skoglund ◽  
Matthew Spriggs ◽  
Frederique Valentin ◽  
Stuart Bedford ◽  
...  

SummaryAncient DNA analysis of three individuals dated to ~3000 years before present (BP) from Vanuatu and one ~2600 BP individual from Tonga has revealed that the first inhabitants of Remote Oceania (“First Remote Oceanians”) were almost entirely of East Asian ancestry, and thus their ancestors passed New Guinea, the Bismarck Archipelago, and the Solomon Islands with minimal admixture with the Papuan groups they encountered [1]. However, all present-day populations in Near and Remote Oceania harbor 25-100% Papuan ancestry, implying that there must have been at least one later stream of migration eastward from Near Oceania. We generated genome-wide data for 14 ancient individuals from Efate and Epi Islands in Vanuatu ranging from 3,000-150 BP, along with 185 present-day Vanuatu individuals from 18 islands. We show that people of almost entirely Papuan ancestry had arrived in Vanuatu by 2400 BP, an event that coincided with the end of the Lapita cultural period, changes in skeletal morphology, and the cessation of long-distance trade between Near and Remote Oceania [2]. First Remote Oceanian ancestry subsequently increased via admixture but remains at 10-20% in most islands. Through a fine-grained comparison of ancestry profiles in Vanuatu and Polynesia with diverse groups in Near Oceania, we find that Papuan ancestry in Vanuatu is consistent with deriving from the Bismarck Archipelago instead of the geographically closer Solomon Islands. Papuan ancestry in Polynesia also shows connections to the ancestry profiles present in the Bismarck Archipelago but is more similar to Tolai from New Britain and Tutuba from Vanuatu than to the ancient Vanuatu individuals and the great majority of present-day Vanuatu populations. This suggests a third eastward stream of migration from Near to Remote Oceania bringing a different type of Papuan ancestry.

2018 ◽  
Author(s):  
Iosif Lazaridis ◽  
Anna Belfer-Cohen ◽  
Swapan Mallick ◽  
Nick Patterson ◽  
Olivia Cheronet ◽  
...  

AbstractThe earliest ancient DNA data of modern humans from Europe dates to ∼40 thousand years ago1-4, but that from the Caucasus and the Near East to only ∼14 thousand years ago5,6, from populations who lived long after the Last Glacial Maximum (LGM) ∼26.5-19 thousand years ago7. To address this imbalance and to better understand the relationship of Europeans and Near Easterners, we report genome-wide data from two ∼26 thousand year old individuals from Dzudzuana Cave in Georgia in the Caucasus from around the beginning of the LGM. Surprisingly, the Dzudzuana population was more closely related to early agriculturalists from western Anatolia ∼8 thousand years ago8 than to the hunter-gatherers of the Caucasus from the same region of western Georgia of ∼13-10 thousand years ago5. Most of the Dzudzuana population’s ancestry was deeply related to the post-glacial western European hunter-gatherers of the ‘Villabruna cluster’3, but it also had ancestry from a lineage that had separated from the great majority of non-African populations before they separated from each other, proving that such ‘Basal Eurasians’6,9 were present in West Eurasia twice as early as previously recorded5,6. We document major population turnover in the Near East after the time of Dzudzuana, showing that the highly differentiated Holocene populations of the region6 were formed by ‘Ancient North Eurasian’3,9,10 admixture into the Caucasus and Iran and North African11,12 admixture into the Natufians of the Levant. We finally show that the Dzudzuana population contributed the majority of the ancestry of post-Ice Age people in the Near East, North Africa, and even parts of Europe, thereby becoming the largest single contributor of ancestry of all present-day West Eurasians.


2017 ◽  
Author(s):  
Irina Pugach ◽  
Ana T. Duggan ◽  
D. Andrew Merriwether ◽  
Françoise R. Friedlaender ◽  
Jonathan S. Friedlaender ◽  
...  

ABSTRACTA widely accepted two-wave scenario of human settlement of Oceania involves the first out-of-Africa migration ca 50,000 ya, and one of the most geographically-widespread dispersals of people, known as the Austronesian expansion, which reached the Bismarck Archipelago by about 3,450 ya. While earlier genetic studies provided evidence for extensive sex-biased admixture between the incoming and the indigenous populations, some archaeological, linguistic and genetic evidence indicates a more complicated picture of settlement. To study regional variation in Oceania in more detail, we have compiled a genome-wide dataset of 823 individuals from 72 populations (including 50 populations from Oceania) and over 620,000 autosomal SNPs. We show that the initial dispersal of people from the Bismarck Archipelago into Remote Oceania occurred in a “leapfrog” fashion, completely by-passing the main chain of the Solomon Islands, and that the colonization of the Solomon Islands proceeded in a bi-directional manner. Our results also support a divergence between western and eastern Solomons, in agreement with the sharp linguistic divide known as the Tryon-Hackman line. We also report substantial post-Austronesian gene flow across the Solomons. In particular, Santa Cruz (in Remote Oceania) exhibits extraordinarily high levels of Papuan ancestry that cannot be explained by a simple bottleneck/founder event scenario. Finally, we use simulations to show that discrepancies between different methods for dating admixture likely reflect different sensitivities of the methods to multiple admixture events from the same (or similar) sources. Overall, this study points to the importance of fine-scale sampling to understand the complexities of human population history.


Radiocarbon ◽  
1988 ◽  
Vol 30 (2) ◽  
pp. 161-169 ◽  
Author(s):  
P V Kirch ◽  
T L Hunt

Three decades of archaeological excavations in Melanesia and Western Polynesia have led to a consensus among Oceanic prehistorians that the initial human colonization of the southwestern Pacific (east of the Solomons) was effected by populations of the Lapita Cultural Complex (Green, 1979; Kirch, 1982, 1984; Allen, 1984; Spriggs, 1984). Although the western Melanesian islands of New Guinea, the Bismarck Archipelago, and possibly the Solomon Islands were settled in the late Pleistocene by small hunter-gatherer populations (Downie & White, 1979; Specht, Lilley & Normu, 1981; Groubeet al, 1986), discovery and occupation by humans of the more remote island chains to the east required sophisticated voyaging and colonization strategies. That the Austronesian-speaking Lapita people possessed long-distance voyaging craft is suggested both by lexical reconstructions, and by the archaeological evidence of long-distance transport of obsidian and other exotic materials over distances of up to 3700km (Ambrose & Green, 1972; Best, 1987). Lapita sites are marked by a distinctive complex of dentate-stamped earthenware ceramics, and associated shell, bone, and stone artifacts. Sites yielding such assemblages have been recorded between the Bismarck Archipelago in the west, through Melanesia, and as far east as Samoa and Tonga, a straight-line distance of ca 4500km.


Sensors ◽  
2021 ◽  
Vol 21 (9) ◽  
pp. 3281
Author(s):  
Xu He ◽  
Yong Yin

Recently, deep learning-based techniques have shown great power in image inpainting especially dealing with squared holes. However, they fail to generate plausible results inside the missing regions for irregular and large holes as there is a lack of understanding between missing regions and existing counterparts. To overcome this limitation, we combine two non-local mechanisms including a contextual attention module (CAM) and an implicit diversified Markov random fields (ID-MRF) loss with a multi-scale architecture which uses several dense fusion blocks (DFB) based on the dense combination of dilated convolution to guide the generative network to restore discontinuous and continuous large masked areas. To prevent color discrepancies and grid-like artifacts, we apply the ID-MRF loss to improve the visual appearance by comparing similarities of long-distance feature patches. To further capture the long-term relationship of different regions in large missing regions, we introduce the CAM. Although CAM has the ability to create plausible results via reconstructing refined features, it depends on initial predicted results. Hence, we employ the DFB to obtain larger and more effective receptive fields, which benefits to predict more precise and fine-grained information for CAM. Extensive experiments on two widely-used datasets demonstrate that our proposed framework significantly outperforms the state-of-the-art approaches both in quantity and quality.


2003 ◽  
Vol 25 (1) ◽  
pp. 41 ◽  
Author(s):  
JM Macaranas ◽  
D Colgan ◽  
S Ingleby

The taxonomic status of fruitbats belonging to the genera Nyctimene and Rousettus from the Solomon Islands was investigated using allozyme electrophoresis. Two populations from the Bismarck Archipelago (Papua New Guinea) were included as reference profiles. The allozyme data at 23 loci assigned all specimens into either Nyctimene albiventer or Nyctimene major. The N. albiventer specimens comprised two subspecies, N. a. papuanus from the Bismarck Archipelago and N. a. bougainville from the Solomon Islands. No support was evident for bougainville being a separate species, and indeed the data suggest that N. a. bougainville encompasses the previously described species N. malaita and subspecies N. a. minor. Genetic distances between populations of R. amplexicaudatus from the Bismarck Archipelago and the Solomon Islands were generally low, supporting recent morphological assessments that the subspecies hedigeri, from the majority of the Solomon Islands, should be considered synonymous with subspecies brachyotis. An individual from Choiseul (Solomon Islands) with a distinctive allozyme profile is the only evidence of taxonomic complexity in R. amplexicaudatus.


1998 ◽  
Vol 25 (1) ◽  
pp. 89 ◽  
Author(s):  
Jeffrey D. Miller ◽  
Kirstin A. Dobbs ◽  
Colin J. Limpus ◽  
Neil Mattocks ◽  
André M. Landry Jr

Tag recoveries from four adult female hawksbill turtles, Eretmochelys imbricata, tagged on the Great Barrier Reef, Australia, are reported. Hawksbill turtles on breeding migrations move between Australia and neighbouring countries including Vanuatu, Solomon Islands, Papua New Guinea and Indonesia. Migratory distances between foraging areas and nesting beaches ranged from 368 to 2425 km. A review of data from tag recoveries, genetic analysis and satellite telemetry indicates that adult female hawksbill turtles often exhibit migratory behaviour parallelling that of other marine turtle species. This study refutes the myth that hawksbill turtles remain resident at reefs associated with their nesting beaches.


1998 ◽  
Vol 12 (5) ◽  
pp. 833 ◽  
Author(s):  
Z. T. Stebnicka

Fifty-five species are discussed, keyed and illustrated, including 17 species described as new: Airapus gazelle, A. hollandiae, A. nondugli, A. popondettae, A. wampuensis, A. wauus, Aphodius pseudoreichei, Ataenius warisensis, Cnematoplatys torricellensis, Rhyparus anneae, R. edieae, R. henryi, R. mokaiensis, R. sepikensis, R. sinewitensis, Saprosites enarotadii, S. komumi. Nine species are synonymised: Ataenius canaliculatus Schmidt and Euparia wonga Stebnicka [= Airapus granulator (Harold)]; Euparia frankenbergeri Balthasar and E. spuria Krikken [= Airapus parvispinus (Schmidt)]; E. papuana Petrovitz [= Airapus spinator (Harold)]; Rhyparus australiae Lea, R. orousseti Paulian and R. risbeci Paulian (= R. helophoroides Fairmaire); Saprosites ullrichi Stebnicka (= S. fodori Endrödi). Eleven of the New Guinean species also occur on mainland Australia; the remainder are mostly endemic to New Guinea and its adjacent islands.


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