Subsistence practices, past biodiversity, and anthropogenic impacts revealed by New Zealand-wide ancient DNA survey

New Zealand's geographic isolation, lack of native terrestrial mammals, and Gondwanan origins make it an ideal location to study evolutionary processes. However, since the archipelago was first settled by humans 750 y ago, its unique biodiversity has been under pressure, and today an estimated 49% of the terrestrial avifauna is extinct. Current efforts to conserve the remaining fauna rely on a better understanding of the composition of past ecosystems, as well as the causes and timing of past extinctions. The exact temporal and spatial dynamics of New Zealand's extinct fauna, however, can be difficult to interpret, as only a small proportion of animals are preserved as morphologically identifiable fossils. Here, we conduct a large-scale genetic survey of subfossil bone assemblages to elucidate the impact of humans on the environment in New Zealand. By genetically identifying more than 5,000 nondiagnostic bone fragments from archaeological and paleontological sites, we reconstruct a rich faunal record of 110 species of birds, fish, reptiles, amphibians, and marine mammals. We report evidence of five whale species rarely reported from New Zealand archaeological middens and characterize extinct lineages of leiopelmatid frog (Leiopelma sp.) and kakapo (Strigops habroptilus) haplotypes lost from the gene pool. Taken together, this molecular audit of New Zealand's subfossil record not only contributes to our understanding of past biodiversity and precontact Maori subsistence practices but also provides a more nuanced snapshot of anthropogenic impacts on native fauna after first human arrival

Using ancient DNA to study the origins and dispersal of ancestral Polynesian chickens across the Pacific

The human colonization of Remote Oceania remains one of the great feats of exploration in history, proceeding east from Asia across the vast expanse of the Pacific Ocean. Human commensal and domesticated species were widely transported as part of this diaspora, possibly as far as South America. We sequenced mitochondrial control region DNA from 122 modern and 22 ancient chicken specimens from Polynesia and Island Southeast Asia and used these together with Bayesian modeling methods to examine the human dispersal of chickens across this area. We show that specific techniques are essential to remove contaminating modern DNA from experiments, which appear to have impacted previous studies of Pacific chickens. In contrast to previous reports, we find that all ancient specimens and a high proportion of the modern chickens possess a group of unique, closely-related, haplotypes found only in the Pacific. This group of haplotypes appears to represent the authentic founding mitochondrial DNA chicken lineages transported across the Pacific, and allows the early dispersal of chickens across Micronesia and Polynesia to be modeled. Importantly, chickens carrying this genetic signature persist on several Pacific islands at high frequencies, suggesting that the original Polynesian chicken lineages may still survive. No early South American chicken samples have been detected with the diagnostic Polynesian mtDNA haplotypes, arguing against reports that chickens provide evidence of Polynesian contact with pre-European South America. Two modern specimens from the Philippines carry haplotypes similar to the ancient Pacific samples, providing clues about a potential homeland for the Polynesian chicken.Vicki A. Thomson, Ophélie Lebrasseur, Jeremy J. Austin, Terry Hunt, David Burney, Tim Denham, Nicolas J. Rawlence, Jamie R. Wood, Jaime Gongora, Linus Girdland Flink, Anna Linderholm, Keith Dobney, Greger Larson, Alan Cooper

Ancient DNA reveals elephant birds and kiwi are sister taxa and clarifies ratite bird evolution

Author version made available in accordance with Publisher copyright policy.The evolution of the ratite birds has been widely attributed to vicariant speciation, driven by the Cretaceous breakup of the supercontinent Gondwana. The early isolation of Africa and Madagascar implies that the ostrich and extinct Madagascan elephant birds (Aepyornithidae) should be the oldest ratite lineages. We sequenced the mitochondrial genomes of two elephant birds and performed phylogenetic analyses, which revealed that these birds are the closest relatives of the New Zealand kiwi and are distant from the basal ratite lineage of ostriches. This unexpected result strongly contradicts continental vicariance and instead supports flighted dispersal in all major ratite lineages. We suggest that convergence toward gigantism and flightlessness was facilitated by early Tertiary expansion into the diurnal herbivory niche after the extinction of the dinosaurs

Disabling XAuthors, Disordering TextsX: Deconstructing Disability and Identity in ChangingX Times

Drawing on Badiou’s writing, we develop new insights on some central notions of the discourse on “disability.” We offer eight agonistic, intersecting trajectories addressing these concepts. Drawing on authorial voices, we criticize the grammatical and rhetorical maneuvers we have previously undertaken as we represent ourselves aiming for forms of participatory engagement, thus offering both critique and self-critique. Previous poststructuralist accounts in this area have drawn on “philosophers of difference,” but mainly Deleuze and Guattari. This piece offers innovation in harnessing aspects of Badiou’s thinking to issues surrounding “discourses of disability” and notions of the research “self” in its various “impersonations.

More than one way of being a moa: differences in leg bone robustness map divergent evolutionary trajectories in Dinornithidae and Emeidae (Dinornithiformes).

The extinct moa of New Zealand included three families (Megalapterygidae; Dinornithidae; Emeidae) of flightless palaeognath bird, ranging in mass from 200 kg. They are perceived to have evolved extremely robust leg bones, yet current estimates of body mass have very wide confidence intervals. Without reliable estimators of mass, the extent to which dinornithid and emeid hindlimbs were more robust than modern species remains unclear. Using the convex hull volumetric-based method on CT-scanned skeletons, we estimate the mass of a female Dinornis robustus (Dinornithidae) at 196 kg (range 155-245 kg) and of a female Pachyornis australis (Emeidae) as 50 kg (range 33-68 kg). Finite element analysis of CT-scanned femora and tibiotarsi of two moa and six species of modern palaeognath showed that P. australis experienced the lowest values for stress under all loading conditions, confirming it to be highly robust. In contrast, stress values in the femur of D. robustus were similar to those of modern flightless birds, whereas the tibiotarsus experienced the highest level of stress of any palaeognath. We consider that these two families of Dinornithiformes diverged in their biomechanical responses to selection for robustness and mobility, and exaggerated hindlimb strength was not the only successful evolutionary pathway

Limitations and recommendations for successful DNA extraction from forensic soil samples: a review

Abstract not availableJennifer M. Young, Nicolas J. Rawlence, Laura S. Weyrich, Alan Coope

Ecology and environmental history, not just genetic diversity, brings important perspectives to defining species diversity — illustrated by moas

We examine whether mitochondrial DNA (mtDNA) data can be used by itself to identify species limits in the extinct New Zealand moa, an order of birds that for the past 150 years has been difficult to classify. We argue that generally it cannot, and that a range of historical population parameters need to be considered when interpreting genetic and morphological diversity. We use the moas Emeus, Dinornis and Megalapteryx (Aves: Dinornithiformes) as examples. These taxa had very divergent palaeoecological preferences, and their ranges were affected quite differently during the glacial - interglacial cycles of the Pleistocene. We show that mtDNA diversity and genetic distances within and between these moa species is directly related to predicted population sizes over the preceding glacial period, and the likely geological longevity of populations in different areas. The interaction of these factors has produced a wide range of intraspecific diversity within moa genera, which illustrates why a simple quantitative cutoff value for genetic distance cannot be used to define species limits in moa (and potentially other taxa)

A deposition mechanism for Holocene miring bone deposits, South Island, New Zealand

Localised deposits of Late Pleistocene and Holocene bird bones occur in wetlands throughout New Zealand. These are characterised by dense accumulations of mostly disarticulated bones, with assemblages dominated by large, flightless bird taxa; in particular the extinct ratite moa (Aves: Dinornithiformes). A wide range of deposition mechanisms were historically proposed for these sites, including large floods and stampedes during wildfires. We outline a simple method for analysing the orientation and spatial distribution of bones within these deposits using GIS software, and apply this method to the interpretation of three such deposits from South Island, New Zealand. The results are consistent with non-catastrophic, periodic miring of individual moa. Long bones within these sites were preferentially orientated and subhorizontally inclined, indicating post-deposition disarticulation and movement of the bones within the sediment by sediment liquefaction and raking from the legs of mired birds, with a possible influence from water flow. Small, light skeletal elements were significantly under represented in the deposits. This may be due to post-mortem scavenging or weathering of vertebra and crania, 'pumping' to the surface of light, buoyant elements during liquefaction events, or crushing of these elements by subsequently mired birds.Jamie R. Wood, Trevor H. Worthy, Nicolas J. Rawlence, Susan M. Jones, and Stephen E. Readhttp://www.journaltaphonomy.com/JT-articles/2008/issue1-2008-abstacts.ht