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Many avian species endemic to Aotearoa New Zealand were driven to extinction or reduced to relict populations following successive waves of human arrival, due to hunting, habitat destruction and the introduction of mammalian predators. Among the affected species were the large flightless South Island takahē (Porphyrio hochstetteri) and the moho (North Island takahē; P. mantelli), with the latter rendered extinct and the former reduced to a single relictual population. Little is known about the evolutionary history of these species prior to their decline and/or extinction. Here we sequenced mitochondrial genomes from takahē and moho subfossils (12 takahē and 4 moho) and retrieved comparable sequence data from takahē museum skins (n = 5) and contemporary individuals (n = 17) to examine the phylogeny and recent evolutionary history of these species. Our analyses suggest that prehistoric takahē populations lacked deep phylogeographic structure, in contrast to moho, which exhibited significant spatial genetic structure, albeit based on limited sample sizes (n = 4). Temporal genetic comparisons show that takahē have lost much of their mitochondrial genetic diversity, likely due to a sudden demographic decline soon after human arrival (~750 years ago). Time‐calibrated phylogenetic analyses strongly support a sister species relationship between takahē and moho, suggesting these flightless taxa diverged around 1.5 million years ago, following a single colonisation of New Zealand by a flighted Porphyrio ancestor approximately 4 million years ago. This study highlights the utility of palaeogenetic approaches for informing the conservation and systematic understanding of endangered species whose ranges have been severely restricted by anthropogenic impacts. [ABSTRACT FROM AUTHOR]

Thirty years ago, DNA sequences were obtained from an extinct Aotearoa New Zealand animal for the first time. Since then, ancient DNA research has provided many – often unexpected – insights into the origins of New Zealand's terrestrial and marine vertebrate fauna. Because recent human activities in New Zealand have caused the decline or extinction of many endemic plant, bird, reptile, and marine mammal species, ancient DNA has been instrumental in reconstructing their identities and origins. However, most ancient DNA studies focusing on New Zealand species have been restricted to vertebrates, with small sample sizes, and/or relatively few genetic markers. This has limited their power to infer fine-scale biogeographic patterns, including (pre)historic distributions and range-shifts driven by past climate and environmental change. Recently, 'next-generation' methodological and technological advances have broadened the range of hypotheses that can feasibly be tested with ancient DNA. These advances represent an exciting opportunity for further exploring New Zealand biogeography using ancient DNA, but their promise has not yet been fully realised. In this review, we summarise the last 30 years of ancient DNA research into New Zealand faunal biogeography and highlight key objectives, challenges, and possibilities for the next 30 years and beyond. [ABSTRACT FROM AUTHOR]

Methodological and technological improvements are continually revolutionizing the field of ancient DNA. Most ancient DNA extraction methods require the partial (or complete) destruction of finite museum specimens, which disproportionately impacts small or fragmentary subfossil remains, and future analyses. We present a minimally destructive ancient DNA extraction method optimized for small vertebrate remains. We applied this method to detect lost mainland genetic diversity in the large New Zealand diplodactylid gecko genus Hoplodactylus, which is presently restricted to predator‐free island and mainland sanctuaries. We present the first mitochondrial genomes for New Zealand diplodactylid geckos, recovered from 19 modern, six historical/archival (1898–2011) and 16 Holocene Hoplodactylus duvaucelii sensu latu specimens, and one modern Woodworthia sp. specimen. No obvious damage was observed in post‐extraction micro‐computed tomography reconstructions. All "large gecko" specimens examined from extinct populations were found to be conspecific with extant Hoplodactylus species, suggesting their large relative size evolved only once in the New Zealand diplodactylid radiation. Phylogenetic analyses of Hoplodactylus samples recovered two genetically (and morphologically) distinct North and South Island clades, probably corresponding to distinct species. Finer phylogeographical structuring within Hoplodactylus spp. highlighted the impacts of Late Cenozoic biogeographical barriers, including the opening and closure of Pliocene marine straits, fluctuations in the size and suitability of glacial refugia, and eustatic sea‐level change. Recent mainland extinction obscured these signals from the modern tissue‐derived data. These results highlight the utility of minimally destructive DNA extraction in genomic analyses of less well studied small vertebrate taxa, and the conservation of natural history collections. see also the Perspective by Michael Bunce [ABSTRACT FROM AUTHOR]

Natural history collections worldwide contain a plethora of mollusc shells. Recent studies have detailed the sequencing of DNA extracted from shells up to thousands of years old and from various taphonomic and preservational contexts. However, previous approaches have largely addressed methodological rather than evolutionary research questions. Here, we report the generation of DNA sequence data from mollusc shells using such techniques, applied to Haliotis virginea Gmelin, 1791, a New Zealand abalone, in which morphological variation has led to the recognition of several forms and subspecies. We successfully recovered near‐complete mitogenomes from 22 specimens including 12 dry‐preserved shells up to 60 years old. We used a combination of palaeogenetic techniques that have not previously been applied to shell, including DNA extraction optimized for ultra‐short fragments and hybridization‐capture of single‐stranded DNA libraries. Phylogenetic analyses revealed three major, well‐supported clades comprising samples from: (1) The Three Kings Islands; (2) the Auckland, Chatham and Antipodes Islands; and (3) mainland New Zealand and Campbell Island. This phylogeographic structure does not correspond to the currently recognized forms. Critically, our nonreliance on freshly collected or ethanol‐preserved samples enabled inclusion of topotypes of all recognized subspecies as well as additional difficult‐to‐sample populations. Broader application of these comparatively cost‐effective and reliable methods to modern, historical, archaeological and palaeontological shell samples has the potential to revolutionize invertebrate genetic research. [ABSTRACT FROM AUTHOR]

The pre-human moa fauna of Rakiura Stewart Island is poorly known, and although there is little clear evidence that moa occurred naturally on the island, isolated moa bones are often found associated with archaeological middens. Here we report the discovery and collection of what is likely a naturally deposited partial South Island giant moa (Dinornis robustus) skeleton from West Ruggedy Beach, Rakiura, radiocarbon dated to 1297-1395 CE (95.4% CI). The time of death of this moa overlaps with the early occupation of the island by Māori. However, the discovery of this moa skeleton in a dune environment with the presence of an organic rich layer beneath the skeleton, associated gizzard stones, and an absence of archaeological material/features or any cut marks on the bones indicating a cultural association, suggests this individual likely represents a natural subfossil deposit. We discuss the skeleton in the context of other moa remains found on the island and comment on the occurrence of moa populations on Rakiura, ultimately concluding that this skeleton provides additional evidence for the natural occurrence of moa on Rakiura. [ABSTRACT FROM AUTHOR]

Determining the genetic structure and population dynamics of harvested species are key aspects of effective fisheries management. New Zealand scampi (Metanephrops challengeri) is a species of nethropid lobster that supports a commercial fishery on the continental shelf and slope around New Zealand. To determine the genetic structure and historical population demography of New Zealand scampi, we sequenced a 623 base-pair fragment of the mitochondrial gene cytochrome c oxidase subunit one (CO1) from 321 individuals across six widely separated sites off the coast of mainland New Zealand and the subantarctic Auckland Islands, representing much of the species' distribution. The Auckland Islands population was found to be genetically distinct from all other sampled populations, potentially resulting from an absence of continuous suitable habitat between the central-eastern South Island and the Auckland Islands. An isolation-by-distance pattern of genetic structure was also detected. With the exception of the Mercury Islands, all sampled populations showed signs of recent population expansion, potentially linked to changes in habitat availability during the glacial-interglacial cycles of the Pleistocene. We recommend that the current NZ scampi management areas and harvesting rates for each remain unchanged. [ABSTRACT FROM AUTHOR]