Matthew Leavesley

Human Adaptation and Plant Use in Highland New Guinea 49,000 to 44,000 Years Ago

New Guineas Ancient Colonies Isolated by water, Australia and New Guinea were some of the last major parts of the world colonized by modern humans. Summerhayes et al. (p. 78; see the Perspective by Gosden) describe an archaeological site in the highlands of New Guinea that sheds light on this migration. The record extends back to nearly 50,000 years ago and thus represents one of the earliest known records. Nuts and yams were widely consumed, and the variety of stone tools discovered implies that the early humans may have cleared forest patches to promote the growth of useful plants. Archaeological sites in the New Guinea Highlands trace the arrival of modern humans to nearly 50,000 years ago. After their emergence by 200,000 years before the present in Africa, modern humans colonized the globe, reaching Australia and New Guinea by 40,000 to 50,000 years ago. Understanding how humans lived and adapted to the range of environments in these areas has been difficult because well-preserved settlements are scarce. Data from the New Guinea Highlands (at an elevation of ~2000 meters) demonstrate the exploitation of the endemic nut Pandanus and yams in archaeological sites dated to 49,000 to 36,000 years ago, which are among the oldest human sites in this region. The sites also contain stone tools thought to be used to remove trees, which suggests that the early inhabitants cleared forest patches to promote the growth of useful plants.

Genomic analyses inform on migration events during the peopling of Eurasia

High-coverage whole-genome sequence studies have so far focused on a limited number of geographically restricted populations, or been targeted at specific diseases, such as cancer. Nevertheless, the availability of high-resolution genomic data has led to the development of new methodologies for inferring population history and refuelled the debate on the mutation rate in humans. Here we present the Estonian Biocentre Human Genome Diversity Panel (EGDP), a dataset of 483 high-coverage human genomes from 148 populations worldwide, including 379 new genomes from 125 populations, which we group into diversity and selection sets. We analyse this dataset to refine estimates of continent-wide patterns of heterozygosity, long- and short-distance gene flow, archaic admixture, and changes in effective population size through time as well as for signals of positive or balancing selection. We find a genetic signature in present-day Papuans that suggests that at least 2% of their genome originates from an early and largely extinct expansion of anatomically modern humans (AMHs) out of Africa. Together with evidence from the western Asian fossil record, and admixture between AMHs and Neanderthals predating the main Eurasian expansion, our results contribute to the mounting evidence for the presence of AMHs out of Africa earlier than 75,000 years ago.

A genomic history of Aboriginal Australia

The population history of Aboriginal Australians remains largely uncharacterized. Here we generate high-coverage genomes for 83 Aboriginal Australians (speakers of Pama–Nyungan languages) and 25 Papuans from the New Guinea Highlands. We find that Papuan and Aboriginal Australian ancestors diversified 25–40 thousand years ago (kya), suggesting pre-Holocene population structure in the ancient continent of Sahul (Australia, New Guinea and Tasmania). However, all of the studied Aboriginal Australians descend from a single founding population that differentiated ~10–32 kya. We infer a population expansion in northeast Australia during the Holocene epoch (past 10,000 years) associated with limited gene flow from this region to the rest of Australia, consistent with the spread of the Pama–Nyungan languages. We estimate that Aboriginal Australians and Papuans diverged from Eurasians 51–72 kya, following a single out-of-Africa dispersal, and subsequently admixed with archaic populations. Finally, we report evidence of selection in Aboriginal Australians potentially associated with living in the desert.

New direction in human colonisation of the Pacific: Lapita settlement of south coast New Guinea

Abstract Expansion of Austronesianspeaking peoples from the Bismarck Archipelago out into the Pacific commencing c.3300 cal BP represents the last great chapter of human global colonisation. Bismarck Indonesia Archipelago Papua New Guinea Torres Strait Caution Bay The earliest migrants were bearers of finelymade dentate-stamped Lapita pottery, hitherto found only across Island Melanesia and western Polynesia. We document the first known occurrence of Lapita peoples on the New Guinea mainland. The new Lapita sites date from 2900 to 2500 cal BP and represent a newly-discovered migratory arm of Lapita expansions that moved westwards along the southern New Guinea coast towards Australia. These marine specialists ate shellfish, fish and marine turtles along the Papua New Guinea mainland coast, reflecting subsistence continuities with local pre-Lapita peoples dating back to 4200 cal BP. Lapita artefacts include characteristic ceramics, shell armbands, stone adzes and obsidian tools. Our Lapita discoveries support hypotheses for the migration of pottery-bearing Melanesian marine specialists into Torres Strait of northeast Australia c.2500 cal BP.

High-resolution radiocarbon dating of marine materials in archaeological contexts: radiocarbon marine reservoir variability between Anadara, Gafrarium, Batissa, Polymesoda spp. and Echinoidea at Caution Bay, Southern Coastal Papua New Guinea

The remains of shellfish dominate many coastal archaeological sites in the Pacific and provide a wealth of information about economy, culture, environment and climate. Shells are therefore the logical sample type to develop local and regional radiocarbon chronologies. The calibration of radiocarbon (14C) dates on marine animals is not straightforward, however, requiring an understanding of habitat and dietary preferences as well as detailed knowledge of local ocean conditions. The most complex situations occur where terrestrial influences impinge on the marine environment resulting in both the enrichment and depletion of 14C (Ulm Geoarchaeology 17(4):319–348, 2002; Petchey and Clark Quat Geochronol 6:539–549, 2011). A sampling protocol that combines a high-resolution excavation methodology, selection of short-lived samples identified to species level, and a tri-isotope approach using 14C, δ13C and δ18O, has given us the ability to identify 14C source variation that would otherwise have been obscured. Here, we present new research that details high-resolution mapping of marine 14C reservoir variation between Gafrarium tumidum, Gafrarium pectinatum, Anadara granosa, Anadara antiquata, Batissa violacea, Polymesoda erosa and Echinoidea from the Bogi 1 archaeological site, Caution Bay, southern coastal Papua New Guinea. These isotopes highlight specific dietary, habitat and behavioural variations that are key to obtaining chronological information from shell radiocarbon determinations.

Lapita sites in the Central Province of mainland Papua New Guinea

Abstract For over forty years, archaeologists working along Papua New Guineas southern coastline have sought evidence for early ceramics and its relationship with Lapita wares of Island Melanesia. Failing to find any such evidence of pottery more than 2000 bp, and largely based on the excavation of eight early pottery-bearing sites during the late 1960s into the early 1970s, synchronous colonization some 2000 bp along 500km of the south Papuan coastline by post-Lapita ceramic manufacturers has been posited. This paper presents conclusive evidence for the presence of Lapita ceramics along the Papuan south coast between c. 2500 and 2900 cal. bp, thereby indicating that current models of colonization by ceramicists for the region need to be rethought. We conclude with a brief reflection as to why these Lapita horizons were missed by previous researchers.

A shark-tooth ornament from Pleistocene Sahul

The tooth of a tiger shark, perforated to make a pendant, was lost in New Ireland, New Guinea between 39500 and 28000 years ago. The author argues that this has to be the work of anatomically modern humans, and implies the use of symbolic language not only across the former continent of Sahul, but also Eurasia.

Impact of human colonization on the landscape: A view from the Western Pacific

Abstract: In this paper we review and assess the impact of colonizing peoples on their landscape by focusing on two very different colonizing processes within the western Pacific. The first is the initial human colonization of New Guinea 45,000–40,000 years ago by hunter-foraging populations; the second is the colonization of smaller offshore islands of the Bismarck Archipelago, some 3,300 years ago, by peoples argued to have practiced agriculture: two different colonizing processes by two different groups of peoples with two different social structures practicing two very different subsistence strategies. The impact of these two colonization processes on the environment is compared and contrasted, and commonalities identified for the archaeological and vegetation record.

Prehistoric Hunting Strategies in New Ireland, Papua New Guinea: The Evidence of the Cuscus (Phalanger orientalis) Remains from Buang Merabak Cave

The cuscus, Phalanger orientalis, was probably the most important food source in New Ireland from its introduction 20,000 years ago until the introduction of the pig, Sus scrofa, 3500 years ago. Terrestrial, or land-based, fauna were an essential part of the prehistoric diet because they provided both protein and fat, which were often difficult to obtain from marine resources alone. P. orientalis was an important prey species because New Ireland had a relatively low range of prey taxa. Prior to 20,000 B.P., the New Ireland fauna were relatively meager: the potential terrestrial prey taxa for prehistoric hunters included bats, rats, birds, and reptiles. The introduction of the cuscus dramatically increased the number of individual animals and therefore expanded the island-based protein resource available to prehistoric hunters. This paper investigates the nature of the late Pleistocene to Holocene capture of P. orientalis based on data from Buang Merabak, a central New Ireland cave site, and investigates whether prehistoric hunters captured P. orientalis of a particular age and how this changed over time.

Mitochondrial DNA Variation in Karkar Islanders

We analyzed 375 base pairs (bp) of the first hypervariable region (HVS‐I) of the mitochondrial DNA (mtDNA) control region and intergenic COII/tRNALys 9‐bp deletion from 47 Karkar Islanders (north coast of Papua New Guinea) belonging to the Waskia Papuan language group. To address questions concerning the origin and evolution of this population we compared the Karkar mtDNA haplotypes and haplogroups to those of neighbouring East Asians and Oceanic populations. The results of the phylogeographic analysis show grouping in three different clusters of the Karkar Islander mtDNA lineages: one group of lineages derives from the first Pleistocene settlers of New Guinea‐Island Melanesia, a second set derives from more recent arrivals of Austronesian speaking populations, and the third contains lineages specific to the Karkar Islanders, but still rooted to Austronesian and New Guinea‐Island Melanesia populations. Our results suggest (i) the absence of a strong association between language and mtDNA variation and, (ii) reveal that the mtDNA haplogroups F1a1, M7b1 and E1a, which probably originated in Island Southeast Asia and may be considered signatures of Austronesian population movements, are preserved in the Karkar Islanders but absent in other New Guinea‐Island Melanesian populations. These findings indicate that the Karkar Papuan speakers retained a certain degree of their own genetic uniqueness and a high genetic diversity. We present a hypothesis based on archaeological, linguistic and environmental datasets to argue for a succession of (partial) depopulation and repopulation and expansion events, under conditions of structured interaction, which may explain the variability expressed in the Karkar mtDNA.