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Comprehending ecological dynamics requires not only knowledge of modern communities but also detailed reconstructions of ecosystem history. Ancient DNA (aDNA) metabarcoding allows biodiversity responses to major climatic change to be explored at different spatial and temporal scales. We extracted aDNA preserved in fossil rodent middens to reconstruct late Quaternary vegetation dynamics in the hyperarid Atacama Desert. By comparing our paleo‐informed millennial record with contemporary observations of interannual variations in diversity, we show local plant communities behave differentially at different timescales. In the interannual (years to decades) time frame, only annual herbaceous expand and contract their distributional ranges (emerging from persistent seed banks) in response to precipitation, whereas perennials distribution appears to be extraordinarily resilient. In contrast, at longer timescales (thousands of years) many perennial species were displaced up to 1,000 m downslope during pluvial events. Given ongoing and future natural and anthropogenically induced climate change, our results not only provide baselines for vegetation in the Atacama Desert, but also help to inform how these and other high mountain plant communities may respond to fluctuations of climate in the future. [ABSTRACT FROM AUTHOR]

The emergence of islands has been linked to spectacular radiations of diverse organisms. Although penguins spend much of their lives at sea, they rely on land for nesting, and a high proportion of extant species are endemic to geologically young islands. Islands may thus have been crucial to the evolutionary diversification of penguins. We test this hypothesis using a fossil-calibrated phylogeny of mitochondrial genomes (mitogenomes) from all extant and recently extinct penguin taxa. Our temporal analysis demonstrates that numerous recent island-endemic penguin taxa diverged following the formation of their islands during the Plio-Pleistocene, including the Galápagos (Galápagos Islands), northern rockhopper (Gough Island), erect-crested (Antipodes Islands), Snares crested (Snares) and royal (Macquarie Island) penguins. Our analysis also reveals two new recently extinct island-endemic penguin taxa from New Zealand's Chatham Islands: Eudyptes warhami sp. nov. and a dwarf subspecies of the yellow-eyed penguin, Megadyptes antipodes richdalei ssp. nov. Eudyptes warhami diverged from the Antipodes Islands erect-crested penguin between 1.1 and 2.5 Ma, shortly after the emergence of the Chatham Islands (∼3 Ma). This new finding of recently evolved taxa on this young archipelago provides further evidence that the radiation of penguins over the last 5 Ma has been linked to island emergence. Mitogenomic analyses of all penguin species, and the discovery of two new extinct penguin taxa, highlight the importance of island formation in the diversification of penguins, as well as the extent to which anthropogenic extinctions have affected island-endemic taxa across the Southern Hemisphere's isolated archipelagos. [ABSTRACT FROM AUTHOR]

Knowledge about the diets of New Zealand's extinct moa (Aves: Dinornithiformes) is heavily biased towards just three species (Dinornis robustus , Megalapteryx didinus and Pachyornis elephantopus), which represent about 90% of all identified coprolites and gizzard content samples. By comparison, the diets of the other six moa species are poorly known. Here, we report the discovery of a new coprolite deposit attributed to little bush moa (Anomalopteryx didiformis) based on DNA barcoding and former moa species distributions. The deposit is the southernmost site from which moa coprolites have been recovered and just the second to contain mid-Holocene specimens. Moreover, the deposit provides the longest known temporal span (∼2200 years) of moa coprolites within a stratigraphic context. Pollen and plant DNA from the coprolites, as well as associated plant macrofossils, indicate that the deposit spans a period when the forest canopy was transitioning from Podocarpaceae to silver beech (Lophozonia menziesii) dominance about 6800–4600 years ago. Our analysis of coprolite content supports the current hypothesis that little bush moa browsed trees and shrubs within the forest understorey, but provides new evidence that ferns were also an important part of their diet. Based on this finding, we suggest that moa might once have played a previously unrecognised role in the dispersal of ground fern spores throughout New Zealand forests. • We report the discovery of a mid-Holocene deposit of little bush moa coprolites. • The deposit contains ∼2200 years of moa coprolites within a stratigraphic context. • Little bush moa browsed trees and shrubs within the forest understorey. • We present new evidence that ferns were also an important part of their diet. [ABSTRACT FROM AUTHOR]

It is indisputable that much of Australia's modern biodiversity decline was triggered by European settlement. However, the driver(s) of pre-European extinctions and extirpations are more challenging to identify, particularly on islands where animals are faced with the additional pressures imposed by isolation. Kangaroo Island, South Australia, has been identified as a potential haven for the reintroduction of endangered animals, but the genetic relationship between reintroduction candidates on the mainland and their extinct relatives on Kangaroo Island is poorly understood. Here, we present a late Pleistocene to mid-Holocene genetic record from Kangaroo Island based on bulk bone metabarcoding of two thousand bone fragments excavated from Kelly Hill Cave. We detect 33 species of bird, reptile, fish and mammal and report additional intra-specific genetic diversity in Kangaroo Island's now extinct population of spotted-tailed quoll. Furthermore, we provide genetic evidence that the Eastern grey kangaroo formerly inhabited Kangaroo Island. Taken together, these data establish a more complete baseline of local biodiversity against which reintroduction programmes and bushfire recovery measures can be evaluated, which is more important than ever in light of the recent fires that devastated much of Kangaroo Island's flora and fauna. • A genetic biodiversity baseline for Kangaroo Island before European arrival. • Genetic identification of 33 species of bird, reptile, fish and mammal. • New haplotypes from the extinct Kangaroo Island population of spotted-tailed quoll. • Genetic evidence that the Eastern grey kangaroo once inhabited Kangaroo Island. [ABSTRACT FROM AUTHOR]