Allozyme and mitochondrial DNA variability within the New Zealand damselfly genera Xanthocnemis, Austrolestes, and Ischnura (Odonata)

We collected larval damselflies from 17 sites in the North, South and Chatham Islands, and tested the hypotheses that: (1) genetic markers (e.g., allozymes, mtDNA) would successfully ¬discriminate taxa; and (2) the dispersal capabilities of adult damselflies would limit differentiation among locations. Four species from three genera were identified based on available taxonomic keys. Using 11 allozyme loci and the mitochondrial cytochrome c-oxidase subunit I (COI) gene, we confirmed that all taxa were clearly discernible. We found evidence for low to moderate differentiation among locations based on allozyme (mean FST = 0.09) and sequence (COI) divergence (<0.034). No obvious patterns with respect to geographic location were detected, although slight differences were found between New Zealand’s main islands (North Island, South Island) and the Chatham Islands for A. colensonis (sequence divergence 0.030–0.034). We also found limited intraspecific genetic variability based on allozyme data (Hexp < 0.06 in all cases). We conclude that levels of gene flow/dispersal on the main islands may have been sufficient to maintain the observed homogeneous population structure, and that genetic techniques, particularly the COI gene locus, will be a useful aid in future identifications

Are current ecological restoration practices capturing natural levels of genetic diversity? A New Zealand case study using AFLP and ISSR data from mahoe (Melicytus ramiflorus)

Sourcing plant species of local provenance (eco-sourcing) has become standard practice in plant community restoration projects. Along with established ecological restoration practices, knowledge of genetic variation in existing and restored forest fragments is important for ensuring the maintenance of natural levels of genetic variation and connectivity (gene flow) among populations. The application of restoration genetics often employs anonymous ‘fingerprinting’ markers in combination with limited sample sizes due to financial constraints. Here, we used two such marker systems, AFLPs and ISSRs, to estimate population-level genetic variation of a frequently used species in restoration projects in New Zealand, māhoe (Melicytus ramiflorus, Violaceae). We examined two rural and two urban forest fragments, as potential local source populations, to determine whether the māhoe population at the recently (re)constructed ecosystem at Waiwhakareke Natural Heritage Park (WNHP), Hamilton, New Zealand reflects the genetic variation observed in these four potential source populations. Both marker systems produced similar results and indicated, even with small population sizes, that levels of genetic variation at WNHP were comparable to in situ populations. However, the AFLPs did provide finer resolution of the population genetic structure than ISSRs. ISSRs, which are less expensive and technically less demanding to generate than AFLPs, may be sufficient for restoration projects where only a broad level of genotypic resolution is required. We recommend the use of AFLPs when species with a high conservation status are being used due to the greater resolution of this technique

Evolution of sociality by natural selection on variances in reproductive fitness: evidence from a social bee

<p>Abstract</p> <p>Background</p> <p>The Central Limit Theorem (CLT) is a statistical principle that states that as the number of repeated samples from any population increase, the variance among sample means will decrease and means will become more normally distributed. It has been conjectured that the CLT has the potential to provide benefits for group living in some animals via greater predictability in food acquisition, if the number of foraging bouts increases with group size. The potential existence of benefits for group living derived from a purely statistical principle is highly intriguing and it has implications for the origins of sociality.</p> <p>Results</p> <p>Here we show that in a social allodapine bee the relationship between cumulative food acquisition (measured as total brood weight) and colony size accords with the CLT. We show that deviations from expected food income decrease with group size, and that brood weights become more normally distributed both over time and with increasing colony size, as predicted by the CLT. Larger colonies are better able to match egg production to expected food intake, and better able to avoid costs associated with producing more brood than can be reared while reducing the risk of under-exploiting the food resources that may be available.</p> <p>Conclusion</p> <p>These benefits to group living derive from a purely statistical principle, rather than from ecological, ergonomic or genetic factors, and could apply to a wide variety of species. This in turn suggests that the CLT may provide benefits at the early evolutionary stages of sociality and that evolution of group size could result from selection on variances in reproductive fitness. In addition, they may help explain why sociality has evolved in some groups and not others.</p

Tracking the origins of the introduced terrestrial amphipod, Puhuruhuru patersoni, on sub-Antarctic Macquarie Island

The terrestrial amphipod Puhuruhuru patersoni (Amphipoda: Talitridae) was discovered on sub-Antarctic Macquarie Island in 1992. The species is only known to naturally occur on New Zealand’s South Island and some associated offshore islands. The possible routes by which the species was introduced to Macquarie Island have previously been considered based on morphology and historic activities between New Zealand and Macquarie Island. Here, we sampled across the known range for P. patersoni and generated mtDNA COI data for these specimens to investigate the likely origin of the Macquarie Island incursion. Our results showed high genetic diversity across the native range and substantially lower genetic diversity on Macquarie Island. Additionally, our phylogenetic reconstructions suggested that the source of the introduction to Macquarie Island is likely to have been from the southern region of New Zealand’s South Island

Comparing plasma and faecal measures of steroid hormones in Adelie penguins Pygoscelis adeliae

Physiological measurements of both stress and sex hormones are often used to estimate the consequences of natural or human-induced change in ecological studies of various animals. Different methods of hormone measurement exist, potentially explaining variation in results across studies; methods should be cross-validated to ensure that they correlate. We directly compared faecal and plasma hormone measurements for the first time in a wild free-living species, the Adelie penguin (Pygoscelis adeliae). Blood and faecal samples were simultaneously collected from individual penguins for comparison and assayed for testosterone and corticosterone (or their metabolites). Sex differences and variability within each measure, and correlation of values across measures were compared. For both hormones, plasma samples showed greater variation than faecal samples. Males had higher mean corticosterone concentrations than females, but the difference was only statistically significant in faecal samples. Plasma testosterone, but not faecal testosterone, was significantly higher in males than females. Correlation between sample types was poor overall, and weaker in females than in males, perhaps because measures from plasma represent hormones that are both free and bound to globulins, whereas measures from faeces represent only the free portion. Faecal samples also represent a cumulative measure of hormones over time, as opposed to a plasma ‘snapshot’ concentration. Our data indicate that faecal sampling appears more suitable for assessing baseline hormone concentrations, whilst plasma sampling may best define immediate responses to environmental events. Consequently, future studies should ensure that they select the most appropriate matrix and method of hormone measurement to answer their research questions

Psychological and psychophysiological effects of recuperative music post-exercise

Purpose: Few studies have examined the psychological and psychophysiological effects of recuperative music following exhaustive exercise. The main purpose of the present study was to examine the effects of two music conditions compared with a no-music control on psychological and psychophysiological recovery processes post-exercise. Methods: A randomized, fully counterbalanced, crossover design was used. Core affect, salivary cortisol, heart rate, and blood pressure were measured before exhaustive exercise, immediately after, and in 10-, 20-, and 30-min intervals during passive recovery (21 women and 21 men; 20.9 ± 1.7 yr) over three separate trials (slow, sedative music; fast, stimulative music; no-music control). The exercise task entailed incremental cycle ergometry performed at 75 rpm with a 22.5 W.min-1 increase in intensity at the end of each minute until exhaustion. Data were analyzed using mixed-model 3 (condition) x 4 (time) x 2 (gender) MANOVA/ANCOVA. Results: The largest decline in affective arousal between active and passive recovery phases was evident in the slow, sedative condition (ηp 2 = 0.50). Women had a more pronounced reduction in arousal than men in the slow, sedative music condition. Heart rate measures showed that fast, stimulative music inhibited the return of heart rate toward resting levels (ηp 2 = 0.06). Similarly, salivary cortisol levels tended to be lower in response to slow, sedative music (ηp 2 = 0.11). There was a main effect of condition for affective valence indicating that the slow, sedative condition elicited more positive affective responses than the control and fast, stimulative conditions (ηp 2 = 0.12). Conclusions: The present findings support the notion that slow, sedative music can expedite the recovery process immediately after strenuous exercise

Distinct migratory and non-migratory ecotypes of an endemic New Zealand eleotrid (Gobiomorphus cotidianus) – implications for incipient speciation in island freshwater fish species

Background: Many postglacial lakes contain fish species with distinct ecomorphs. Similar evolutionary scenarios might be acting on evolutionarily young fish communities in lakes of remote islands. One process that drives diversification in island freshwater fish species is the colonization of depauperate freshwater environments by diadromous (migratory) taxa, which secondarily lose their migratory behaviour. The loss of migration limits dispersal and gene flow between distant populations, and, therefore, is expected to facilitate local morphological and genetic differentiation. To date, most studies have focused on interspecific relationships among migratory species and their non-migratory sister taxa. We hypothesize that the loss of migration facilitates intraspecific morphological, behavioural, and genetic differentiation between migratory and non-migratory populations of facultatively diadromous taxa, and, hence, incipient speciation of island freshwater fish species. Results: Microchemical analyses of otolith isotopes (Sr-88, Ba-137 and Ca-43) differentiated migratory and non-migratory stocks of the New Zealand endemic Gobiomorphus cotidianus McDowall (Eleotridae). Samples were taken from two rivers, one lake and two geographically-separated outgroup locations. Meristic analyses of oculoscapular lateral line canals documented a gradual reduction of these structures in the non-migratory populations. Amplified fragment length polymorphism (AFLP) fingerprints revealed considerable genetic isolation between migratory and non-migratory populations. Temporal differences in reproductive timing (migratory = winter spawners, non-migratory = summer spawners; as inferred from gonadosomatic indices) provide a prezygotic reproductive isolation mechanism between the two ecotypes. Conclusion: This study provides a holistic look at the role of diadromy in incipient speciation of island freshwater fish species. All four analytical approaches (otolith microchemistry, morphology, spawning timing, population genetics) yield congruent results, and provide clear and independent evidence for the existence of distinct migratory and non-migratory ecotypes within a river in a geographically confined range. The morphological changes within the non-migratory populations parallel interspecific patterns observed in all non-migratory New Zealand endemic Gobiomorphus species and other derived gobiid taxa, a pattern suggesting parallel evolution. This study indicates, for the first time, that distinct ecotypes of island freshwater fish species may be formed as a consequence of loss of migration and subsequent diversification. Therefore, if reproductive isolation persists, these processes may provide a mechanism to facilitate speciation

House mouse colonization patterns on the sub-Antarctic Kerguelen Archipelago suggest singular primary invasions and resilience against re-invasion

Starting from Western Europe, the house mouse (Mus musculus domesticus) has spread across the globe in historic times. However, most oceanic islands were colonized by mice only within the past 300 years. This makes them an excellent model for studying the evolutionary processes during early stages of new colonization. We have focused here on the Kerguelen Archipelago, located within the sub-Antarctic area and compare the patterns with samples from other Southern Ocean islands

The use of different 16S rRNA gene variable regions in biogeographical studies

DATA AVAILABILITY STATEMENT : All Illumina sequences generated and analyzed in this study were deposited into the European Nucleotide Archive (accession number PRJEB55051).SUPPORTING INFORMATION 1 : FIGURE S1. Samples located in four inland areas of the Prince Charles Mountains (ME1 from Mount Rubin, ME2 and ME3 from Mawson Escarpment, MM1 and MM2 from Mount Menzies, LT1 and LT2 from Lake Terrasovoje), in the Reinbolt Hills (RH1), and in coastal sites in proximity of the Prince Charles Mountains (C1 and C2; see Table S1). Map was produced using MODIS mosaic (125 m) imagery distributed by Quantarctica (https://cmr.earthdata.nasa.gov/; https://www.npolar.no/quantarctica/). FIGURE S2. Pearson's pairwise correlations between Bray–Curtis dissimilarity matrices calculated on relative abundance taxonomic dataset (genus level; A), and between Jaccard dissimilarity matrices calculated on presence/absence taxonomic dataset (genus level; B). Correlations were calculated for all the variable region datasets (V1–V3, V3–V4, V4, V4–V5 and V8–V9), and the mixed datasets (Mix 1, Mix 2 and Mix 3) constituted by randomly picked samples from V1–V3, V3–V4, V4, V4–V5 and V8–V9 (Table S4). Pearson's correlation coefficients (r) are reported only in case of significant correlation (p < 0.05).SUPPORTING INFORMATION 2 : TABLE S1. Sample specifics. TABLE S2. Geochemical data. TABLE S3. Relative abundance (%) of the taxonomic domains Bacteria and Archaea in sample (i.e., ME1, ME2, ME3, MM1, MM2, LT1, LT2, RH1, C1 and C2) for each variable region dataset (i.e., V1–V3, V3–V4, V4, V4–V5 and V8–V9). TABLE S4. Composition of mixed communities. TABLE S5. Number of reads at each step of the 16S rRNA gene processing pipeline. *counts reported as read pairs. TABLE S6. Number and percentage of unknown amplicon sequence variants (ASVs) at genus level for each phylum. TABLE S7. Relative abundance associated to unknown amplicon sequence variants at genus-level for each phylum. TABLE S8. Pearson's correlations from pairwise comparisons of variable region datasets performed on number of genera (A), dominant genera (i.e., genera represented by a relative abundance higher than 1% in at least one sample) (B), rare genera (i.e., genera represented by a relative abundance lower than 0.1% in all samples (C), Shannon index (D) and unique genera (E).16S rRNA gene amplicon sequencing is routinely used in environmental surveys to identify microbial diversity and composition of the samples of interest. The dominant sequencing technology of the past decade (Illumina) is based on the sequencing of 16S rRNA hypervariable regions. Online sequence data repositories, which represent an invaluable resource for investigating microbial distributional patterns across spatial, environmental or temporal scales, contain amplicon datasets from diverse 16S rRNA gene variable regions. However, the utility of these sequence datasets is potentially reduced by the use of different 16S rRNA gene amplified regions. By comparing 10 Antarctic soil samples sequenced for five different 16S rRNA amplicons, we explore whether sequence data derived from diverse 16S rRNA variable regions can be validly used as a resource for biogeographical studies. Patterns of shared and unique taxa differed among samples as a result of variable taxonomic resolutions of the assessed 16S rRNA variable regions. However, our analyses also suggest that the use of multi-primer datasets for biogeographical studies of the domain Bacteria is a valid approach to explore bacterial biogeographical patterns due to the preservation of bacterial taxonomic and diversity patterns across different variable region datasets. We deem composite datasets useful for biogeographical studies.Australian Antarctic Division, Australian Research Council and NRF SANAP.http://wileyonlinelibrary.com/journal/emi4hj2023BiochemistryGeneticsMicrobiology and Plant Patholog

Proton pump inhibitor use and progression to major adverse renal events: a competing risk analysis

Background: Proton pump inhibitors (PPIs) are associated with acute tubulointerstitial nephritis and there are reports associating their use with the development of chronic kidney disease (CKD). Aim: To determine if PPI use is associated with major adverse renal events (MARE) in patients with CKD. Design: Observational cohort study comprising patients with CKD attending secondary care renal clinics from 1 January 2006 until 31 December 2016. Methods: We collated baseline clinical, socio-demographic and biochemical data at start of PPI (PPI group) or study inception (control group). MARE was considered a composite of doubling of creatinine or end-stage renal disease. Association between PPI exposure and progression to MARE was assessed by cause-specific hazards competing risk survival analysis. Results: There were 3824 patients with CKD included in the analyses of whom 1195 were prescribed a PPI. The PPI group was younger (64.8 vs. 67.0 years, P &lt; 0.001), with lower estimated glomerular filtration rate (eGFR) (30 vs. 35 ml/min, P &lt; 0.001) and more proteinuria (64 vs. 48 mg/mmol, P &lt; 0.001). PPI use was associated with progression to MARE on multivariable adjustment (hazard ratio 1.13 [95% confidence interval 1.02–1.25], P = 0.021). Other factors significantly associated with progression to MARE were higher systolic blood pressure, lower eGFR, greater proteinuria, congestive cardiac failure and diabetes. Hypomagnesaemia was more common in the PPI group (39.5 vs. 18.9%, P &lt; 0.001). Conclusion: PPI use was associated with progression to MARE, but not death in patients with CKD after adjusting for factors known to predict declining renal function, including lower eGFR, proteinuria and comorbidities. A prospective cohort study is required to validate these findings