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Unravelling β‐Diversity and the Role of Small Streams in Shaping Fish Communities Using a National‐Scale eDNA DatabaseNARA Subscribed
The role of river size on fish communities remains underexplored in freshwater ecology. Small streams, despite accounting for 75% of stream length, are more vulnerable to human impacts and often lack legislative protection. Nevertheless, they can serve as refuges and rearing areas for fish, including rare or threatened species. To understand if small streams host distinct fish assemblages, we analysed fish β‐diversity across s...
Using Drone‐Derived Imagery to Describe Prey Sharing Behaviors in Two Piscivorous Resident Killer Whale PopulationsNARA Subscribed
Cooperative foraging occurs across diverse taxa and facilitates prey acquisition and social learning, particularly when prey is shared among group members. In Resident killer whales ( Orcinus orca ater ), prey sharing is central to how individuals acquire salmonid prey, yet current research has relied primarily on boat‐based observations. Using 10 years of drone‐based imagery, we examined prey sharing behaviors in two populati...
A balanced approach to the potential of octopus aquacultureNARA Subscribed
Antarctic soils are unique from those found nearly anywhere else on Earth yet can still harbor a broad diversity of microorganisms able to tolerate the challenging conditions typical of the continent. For these reasons, microbiologists have been drawn to Antarctica for decades. However, our understanding of which microbes thrive in Antarctic soils and how they to do so remains limited. To help resolve these knowledge gaps, we...
Aim Megafire events generate immediate concern for wildlife and human well‐being, but their broader ecological impacts likely extend beyond individual species and single fire events. In the first mechanistic study of fire effects focussed on ecosystems, we aimed to assess the sensitivity and exposure of ecosystems to multiple fire‐related threats, placing impacts in the context of changing fire regimes and their interactions w...
Effects of the neo‐X chromosome on genomic signatures of hybridization in Rumex hastatulusNARA Subscribed
Natural hybrid zones provide opportunities for studies of the evolution of reproductive isolation in wild populations. Although recent investigations have found that the formation of neo‐sex chromosomes is associated with reproductive isolation, the mechanisms remain unclear in most cases. Here, we assess the contemporary structure of gene flow in the contact zone between largely allopatric cytotypes of the dioecious plant Rum...
Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disab...
Captive breeding is often a last resort management option in the conservation of endangered species which can in turn lead to increased risk of inbreeding depression and loss of genetic diversity. Thus, recording breeding events via studbook for the purpose of estimating relatedness, and facilitating mating pair selection to minimize inbreeding, is common practice. However, as founder relatedness is often unknown, loss of gene...
VLBI measurement of the vector baseline between geodetic antennas at Kokee Park Geophysical Observatory, HawaiiNARA Subscribed
We measured the components of the 31-m-long vector between the two very-long-baseline interferometry (VLBI) antennas at the Kokee Park Geophysical Observatory (KPGO), Hawaii, with approximately 1 mm precision using phase delay observables from dedicated VLBI observations in 2016 and 2018. The two KPGO antennas are the 20 m legacy VLBI antenna and the 12 m VLBI Global Observing System (VGOS) antenna. Independent estimates of th...
Harbor porpoise in the North Pacific are found in coastal waters from southern California to Japan, but population structure is poorly known outside of a few local areas. We used multiplexed amplicon sequencing of 292 loci and genotyped clusters of single nucleotide polymoirphisms as microhaplotypes ( N = 271 samples) in addition to mitochondrial (mtDNA) sequence data ( N = 413 samples) to examine the genetic structure from sa...
Explaining the worldwide distributions of two highly mobile species: Cakile edentula and Cakile maritimaNARA Subscribed
Aim If we are able to determine the geographic origin of an invasion, as well as its known area of introduction, we can better appreciate the innate environmental tolerance of a species and the strength of selection for adaptation that colonizing populations have undergone. It also enables us to maximize the success of searches for effective biological control agents. We determined the number of successful colonization events...
Hurricane Sandy Effects on Coastal Marsh Elevation ChangeNARA Subscribed
Geographic and temporal dynamics of a global radiation and diversification in the killer whaleNARA Subscribed
Global climate change during the Late Pleistocene periodically encroached and then released habitat during the glacial cycles, causing range expansions and contractions in some species. These dynamics have played a major role in geographic radiations, diversification and speciation. We investigate these dynamics in the most widely distributed of marine mammals, the killer whale ( Orcinus orca ), using a global data set of over...
Understanding the spectacular failure of DNA barcoding in willows ( Salix ): Does this result from a trans‐specific selective sweep?NARA Subscribed
Willows ( Salix : Salicaceae) form a major ecological component of Holarctic floras and consequently are an obvious target for a DNA ‐based identification system. We surveyed two to seven plastid genome regions (~3.8 kb; ~3% of the genome) from 71 Salix species across all five subgenera, to assess their performance as DNA barcode markers. Although Salix has a relatively high level of interspecific hybridization, this may not s...
Spatial patterns of recreational exploitation in eastern A ustralian ROFA s: implications for zonal managementNARA Subscribed
Effective management of recreational fisheries requires information on fine‐scale spatial patterns of recreational exploitation. Such information is particularly important for specially designated regions such as recreational‐only fishing areas ( ROFA s). Using data acquired through progressive counts and interview‐based surveys, this study quantitatively compared recreational effort, harvest‐per‐unit‐effort ( HPUE ) and speci...
Our understanding of the spatial organization of root diversity in plant communities and of the mechanisms of community assembly has been limited by our ability to identify plants based on root tissue, especially in diverse communities. Here, we test the effectiveness of the plastid gene rbcL , a core plant DNA barcoding marker, for investigating spatial patterns of root diversity, and relate observed patterns to above‐ground...
Population structure and diversity in sexual and asexual populations of the pathogenic fungus Melampsora liniNARA Subscribed
Many pathogens undergo both sexual and asexual reproduction to varying degrees, yet the ecological, genetic and evolutionary consequences of different reproductive strategies remain poorly understood. Here we investigate the population genetic structure of wild populations of the plant pathogen Melampsora lini on its host Linum marginale , using amplified fragment length polymorphism (AFLP) markers, two genes underlying pathog...