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Background: The minimum weight for enterostomy closure (EC) in infants remains debated with the current acceptable cut-off of >2 kg. As enterostomy-related complications or high enterostomy output (>30cc/kg/d) may prohibit a premature infant fromreaching 2 kg, additional data is needed to evaluate the safety of EC in infants <2 kg. The objective of this study was to evaluate postoperative outcomes in low body weight (<2 kg) infants undergoing EC compared to larger infants. Methods: We performed a multi-center retrospective analysis from 1/1/2012-12/31/2022 of all infants (age <1 year) who were <4 kg at time of EC. Primary outcomes included postoperative complications and 30-day mortality. Nonparametric analysis was performed using the Kruskal-Wallis one-way analysis of variance and chi-square tests. Univariable logistic regression was performed to identify factors associated with postoperative complications. Results: Of 92 infants, 15 infants (16.3%) underwent EC at <2 kg, 16 (17.4%) at 2-2.49 kg, 31 (33.7%) at 2.5-2.99 kg, and 30 (32.6%) at ≥3 kg. Infants <2 kg at time of EC exhibited higher rates of hyperbilirubinemia (P = .030), neurologic comorbidities (P = .030), and high enterostomy output (P = .041). There was no difference in postoperative complications (P = .460) or 30-day mortality (P = .460) between the <2 kg group and larger weight groups. Low body weight was not associated with an increased risk for developing a postoperative complication (OR: 1.001, 95% CI: 1.001-1.001; P = .032). Conclusion: Our findings suggest that EC in infants <2 kg may be safe with comparable postoperative outcomes to larger weight infants. Thus, the timing of EC should be based on the infant's physiologic status, in contrast to a pre-determined minimum weight cut-off. [ABSTRACT FROM AUTHOR]

Past climate changes have had large impacts on modern ecological patterns. Understanding if legacies are distinguishable in the climatic niches of extant and locally extinct taxa can provide insight into the importance of climate in extinction events. To better understand mid‐ to late‐Cenozoic New Zealand plant extinctions, which are often attributed to Cenozoic climate cooling, we identify 13 con‐familial extinct and extant New Zealand genus pairs, which have modern distributions in Australia. Using climatic niches derived from current geographic distributions in Australia, we compared (i) total niche breadth, (ii) niche overlap, and (iii) individual climate parameters, to investigate potential climate drivers of intrafamilial extinction and persistence patterns in New Zealand. A majority of New Zealand extinct genera (9 out of 13 pairs) do not indicate climate niche legacies consistent with susceptibility to extinction from changing climates, while the remaining four extinct/extant pairs show slight climatic niche legacies. Three extinct genera have warmer niches than their extant counterpart, which is consistent with extinction reflecting intolerance of cooling Cenozoic climates. The other genus pair with a climatic niche legacy has an extinct genus that is distinguished by a niche with smaller precipitation seasonality than its extant counterpart, suggesting that climate metrics other than temperature may also be important extinction drivers in some taxa. Our results show that the mechanisms of Cenozoic extinctions of New Zealand genera are likely more complex than taxa reaching environmental tolerances due to cooling climates. Comparisons of current climatic niches between extant and extinct sister taxa can provide useful insights into large‐scale, long‐term climatic legacies but more analyses, including trait and phylogeographic patterns, would lead to additional insights into alternative pathways of extinction. [ABSTRACT FROM AUTHOR]

Ecosourcing seed of 'local genetic stock' for ecological restoration has been practiced in New Zealand for about 50 years. However, we believe that it has become unnecessarily restrictive. Ecosourcing ensures plants used for restoration are adapted to local conditions and maintains current distributional patterns. It also restricts genetic diversity, confines species to their historic range, and reduces the conservation options for threatened species. For example, New Zealand tree species, the life form most frequently used in restoration plantings, have low population genetic differentiation and high net migration of alleles throughout their range. Therefore, very little is gained through restrictive ecosourcing of tree seed. Furthermore, avoidance of the danger of inbreeding depression and widening the scope for closer environmental matching, argues for larger rather smaller source areas. Climate change, extinctions across multiple trophic levels, habitat loss and fragmentation, spread of invasive species, and novel habitats have completely altered the contemporary biotic landscape. Conservation needs to engage with these changes if it is to protect and restore ecosystems. Restrictive ecosourcing is counter-productive as it limits utilising genotypic, phenotypic and ecotypic diversity, and thus the evolutionary potential of indigenous species and ecosystems. It also reduces opportunities to protect biodiversity when populations are small, and limits response to climate change. A new approach is needed. We recommend that phylogeographic patterns and biogeographic boundaries be used to set nine broad ecosourcing regions and, within these regions, phenotypic adaptation to particular environments be used as a guide to seed selection. This more relaxed approach to ecosourcing will improve restoration outcomes through increasing species and genetic diversity, reducing the detrimental effects of inbreeding and promoting the genetic rescue of populations of threatened species. Examples of adopting an eco-evolutionary approach to ecosourcing are provided for the early-successional coloniser Kunzea ericoides and late-successional conifer species. [ABSTRACT FROM AUTHOR]

Background: Surgical resection is a mainstay of treatment in high-risk neuroblastoma (HR-NB), but there exists wide variability in perioperative management practices. The aim of this study was to evaluate two standardized adult perioperative enhanced recovery practices (ERPs) in pediatric patients undergoing open resection of abdominal HR-NB. Methods: All patients with abdominal HR-NB surgically resected at a free-standing children's hospital between 12/2010 and 7/2020 were retrospectively reviewed. Perioperative ERPs of interest included avoidance of routine nasogastric tube (NGT) use and the use of neuraxial anesthesia. Primary outcomes included time to enteral intake, urinary catheter use, opioid utilization, and length of stay (LOS). Results: Overall, 37 children, median age 33 months (IQR: 20-48 months), were identified. Avoidance of an NGT allowed for earlier feeding after surgery (P =.03). Neuraxial anesthesia use more frequently required an indwelling urinary catheter (P <.01) for a longer duration (P =.02), with no difference in total opioid utilization (P =.77) compared to patients without neuraxial anesthesia. Postoperative LOS was unaffected by avoidance of routine NGT use (P =.68) or use of neuraxial anesthesia (P =.89). Conclusion: Children undergoing open resection of abdominal HR-NB initiated diet sooner when an NGT was not left postoperatively, and the need for a urinary catheter was significantly higher in patients who received neuraxial anesthesia. However, these two ERP components did not decrease postoperative LOS. To optimize the postoperative management of NB patients, postoperative NGTs should be avoided, while the benefit of neuraxial anesthesia is less clear as it necessitates the placement of a urinary catheter without decreasing opioid utilization. [ABSTRACT FROM AUTHOR]

Neuroblastoma (NB) is the most common extra-cranial malignancy in children. Poor survival in high-risk NB is attributed to recurrent metastatic disease. To better study metastatic disease, we used a novel mouse model to investigate differential gene expression between primary tumor cells and metastatic cells. We hypothesized that metastatic NB cells have a different gene expression profile from primary tumor cells and cultured cells. Using three human NB cell lines (NGP, CHLA255, and SH-SY5Y), orthotopic xenografts were established in immunodeficient nod/scid gamma mice via subcapsular renal injection. Mice were sacrificed and NB cells were isolated from the primary tumor and from sites of metastasis (bone marrow, liver). RNA sequencing, gene set analysis, and pathway analysis were performed to identify differentially expressed genes and molecular pathways in the metastatic cells compared to primary tumor cells. There were 266 differentially expressed genes in metastatic tumor cells (bone marrow and liver combined) compared to primary tumor cells. The top upregulated gene was KCNK1 and the top downregulated genes were PDE7B and NEBL. Top upregulated pathways in the metastatic cells were involved in ion transport, cell signaling, and cell proliferation. Top downregulated pathways were involved in DNA synthesis, transcription, and cellular metabolism. In metastatic NB cells, our study identified the upregulation of biologic processes involved in cell cycle regulation, cell proliferation, migration, and invasion. Ongoing studies aim to validate downstream translation of these genomic alterations, as well as target these pathways to more effectively suppress and inhibit recurrent metastatic disease in NB. [ABSTRACT FROM AUTHOR]

Purpose: Pilonidal disease (PD) is marked by chronic inflammation and frequent recurrence which can decrease quality of life. However, debate remains regarding the optimal treatment for PD in the pediatric population. This study compares two recommended treatment approaches—excision with off-midline flap reconstruction (OMF: Bascom cleft lift flap, modified Limberg flap) and minimally invasive endoscopic pilonidal sinus treatment (EPSiT). Methods: Single-center retrospective evaluation of patients 1–21 years of age with PD who underwent either excision with OMF reconstruction or EPSiT between 10/1/2011 and 10/31/2021. Outcomes included were disease recurrence, reoperation, and wound complication rates. Comparisons were performed using Chi-square and Mann–Whitney U tests. Results: 18 patients underwent excision/OMF reconstruction and 45 patients underwent EPSiT. The excision/OMF reconstruction cohort was predominantly male (44.4% vs 17.8% p = 0.028), with history of prior pilonidal infection (33.3% vs 6.7%; p = 0.006), and longer median operative time (60 min vs 17 min; p < 0.001). The excision/OMF reconstruction cohort had a higher rate of wound complications (22.2% vs 0%; p = 0.001), but lower rates of disease recurrence (5.6% vs 33.3%; p = 0.022) and reoperation (5.6% vs 31.1%; p = 0.031). Conclusion: In pediatric patients with PD, excision with OMF reconstruction may decrease recurrence and reoperation rates with increased operative times and wound complication rates, compared to EPSiT. [ABSTRACT FROM AUTHOR]

The novel use of magnetic force to optimize modern surgical techniques originated in the 1970s. Since then, magnets have been utilized as an adjunct or alternative to a wide array of existing surgical procedures, ranging from gastrointestinal to vascular surgery. As the use of magnets in surgery continues to grow, the body of knowledge on magnetic surgical devices from preclinical development to clinical implementation has expanded significantly; however, the current magnetic surgical devices can be organized based on their core function: serving as a guidance system, creating a new connection, recreating a physiologic function, or utilization of an internal–external paired magnet system. The purpose of this article is to discuss the biomedical considerations during magnetic device development and review the current surgical applications of magnetic devices. [ABSTRACT FROM AUTHOR]

Counseling on the immediate postoperative experience for outpatient procedures is largely based on anecdotal experience. We devised a short messaging service (SMS) survey using mobile phone text messages to evaluate real-time patient recovery following outpatient thyroid or parathyroid surgery. Daily automated SMS surveys were sent the evening of the operation until postoperative day 10. Pain, opioid use, voice quality, and energy levels were assessed. Impaired voice and energy was defined as a score < 2/3 of normal. One hundred fifty five patients were enrolled with an overall response rate of 81.6%. One hundred thirty three patients had an individual response rate > 50% and were included in the final analysis. Median patient age was 60 y with 102 females (76.7%). Seventy patients (52.6%) underwent parathyroidectomy and 66 (49.6%) thyroidectomy and 10 (7.5%) neck dissection. Forty eight patients (36.1%) did not use any opioids postoperatively. Independent risk factors for higher total pain scores included thyroidectomy and patients with preoperative opioid or tobacco use, while increased opioid use was associated with age < 60 y, body mass index > 30 kg/m2, preoperative opioid or tobacco use, and history of anxiety or depression. Patients with loss of intraoperative recurrent laryngeal nerve signaling had a significantly worse overall voice score (54.65 versus 92.67, P < 0.001). Up to 10% of patients were still using opioids and/or reported impaired voice and energy levels beyond 1 wk postoperatively. Real-time SMS survey is an effective and potentially valuable way to monitor patient recovery following surgery. A subset of patients reported impaired voice and energy and was still using opioids beyond 1 wk after thyroid and parathyroid surgery and these patients may benefit from closer follow-up and earlier intervention. • Thirty six percent of patients did not use any opioids postoperatively. • Independent risk factors for increased postoperative opioid use were age < 60 y, body mass index > 30, preoperative opioid/tobacco use, and history of anxiety or depression, while loss of intraoperative recurrent laryngeal nerve signal was associated with decreased voice scores postoperatively (i.e., impaired voice). • Use of daily SMS/text message surveys can effectively monitor patient recovery and track outcomes in real-time which can be used to improve patient counseling and identify patient subsets that may benefit from closer follow-up/early intervention. [ABSTRACT FROM AUTHOR]

Background: Gastrostomy creation is a common pediatric surgical procedure, but the time to initiation of feeds and to goal feeding volumes postoperatively varies greatly. Delays in reaching goal feeding volumes promote malnutrition and may prolong hospital length of stay. We hypothesized that implementing an accelerated, standardized post-gastrostomy feeding protocol would allow patients to reach goal feeding volumes sooner, without increasing postoperative complications. Methods: We conducted a retrospective cohort study of children who underwent gastrostomy tube placement between 1/1/2022 and 11/30/2023. The feeding protocol was implemented on 11/16/2022, with patients separated into pre- and post-protocol cohorts. Abstracted data included comorbidities, time to initiation of enteral feeds, time to goal feeding volume, and postoperative complications. Results: 322 patients were included: 166 pre-protocol and 156 post-protocol. The post-protocol cohort had a greater proportion of patients with gastrointestinal and/or cardiac comorbidities (P < .001). Through the protocol, postoperative enteral feeds were initiated significantly faster (5.4 hrs [IQR 43-7.7] vs 7.0 hrs [IQR 5.6-14.3]; P < .001). The postprotocol cohort also achieved goal feeding volumes sooner (12.8 hrs [IQR 9.1-25.3] vs 26.3 hrs [IQR 21.6-38.9]; P < .001). Postoperative complication rates did not differ between cohorts. Sub-analysis of children with complex cardiac conditions also demonstrated faster time to goal nutrition without an associated increase in postoperative events. Discussion: These findings demonstrate that our accelerated post-gastrostomy feeding protocol was effective in achieving goal enteral nutrition earlier without increasing postoperative adverse outcomes. This protocol may be used by other centers to safely expedite time to goal enteral feeds in children postoperatively. [ABSTRACT FROM AUTHOR]

Correlations of non-monocot woody angiosperm leaf traits to macroclimate are often used to reconstruct terrestrial paleoclimate under the assumption that macroclimate correlates with leaf phenotype are globally uniform, regardless of evolutionary history. Here, we evaluate if global trends in leaf trait variation with macroclimate are observed in the predominantly evergreen indigenous flora of New Zealand. A dataset of 557 indigenous woody dicot species and over 100,000 occurrences was employed to investigate community-level relationships of four leaf characters (leaf pubescence, margin teeth, area and length-to-width ratio) with geographic variation in temperature, precipitation, water deficit and solar radiation. Leaf area and the frequency of toothed leaves decline at higher latitudes in New Zealand. Variation in leaf pubescence and leaf teeth is associated primarily with measures of water availability, such as annual rainfall and annual water deficit; whereas leaf size is associated primarily with temperature. Variation in leaf length-to-width ratio was weakly correlated to climate parameters. The New Zealand relationship of leaf area with temperature aligns with global patterns, highlighting the importance of small leaves in limiting night-time chilling. The global negative correlation of leaf teeth with temperature is apparent in New Zealand trees and vines, but not in shrubs or all woody dicots combined. However, the primary correlate of leaf teeth in New Zealand is water availability, showing that the response of this trait to macroclimate is not globally uniform. The high occurrence of pubescent leaves in low rainfall and drought-prone environments in New Zealand suggests that the trait is associated with water retention in drier climates. [ABSTRACT FROM AUTHOR]

Pediatric surgical care is becoming increasingly regionalized, often resulting in limited access. Interfacility transfers pose a significant financial and emotional burden to when they are potentially avoidable. Of transferred patients, we sought to identify clinical factors associated with avoidable transfers in pediatric patients with suspected appendicitis. We performed a single-center retrospective study at an academic tertiary referral children's hospital in an urban setting. We included children who underwent interfacility transfer to our center with a transfer diagnosis of appendicitis from July 1, 2021 to June 30, 2023. Encounters were designated as either an appropriate transfer (underwent appendectomy) or an avoidable transfer (did not undergo appendectomy). Encounters treated nonoperatively for complicated appendicitis were excluded. Bivariate analysis was performed using Mann-Whitney test and chi-square tests. A total of 444 patients were included: 71.2% were classified as appropriate transfers and 28.8% as avoidable transfers. Patients with avoidable transfer were younger compared to those in the appropriate transfer cohort (median age 9 y, interquartile range: 7-13 versus 11 y, interquartile range: 8-14; P < 0.001). Avoidable transfers less frequently presented with the typical symptoms of fever, migratory abdominal pain, anorexia, and nausea/emesis (P = 0.005). Avoidable transfers also reported shorter symptom duration (P = 0.040) with lower median white blood cell count (P < 0.001), neutrophil percentage (P < 0.001), and C-reactive protein levels (P < 0.003). Avoidable transfers more frequently underwent repeat imaging upon arrival (42.9% versus 12.7%, P < 0.001). These findings highlight the importance of clinical history in children with suspected appendicitis. Younger patients without typical symptoms of appendicitis, those with a shorter duration of symptoms, and lower serum inflammatory markers may benefit from close observation without transfer. [ABSTRACT FROM AUTHOR]

Nuclear magnetic resonance (NMR) is potentially a very powerful process analytical technology (PAT) tool as it gives an atomic resolution picture of the reaction mixture without the need for chromatography. NMR is well suited for interrogating transient intermediates, providing kinetic information via NMR active nuclei, and most importantly provides universally quantitative information for all species in solution. This contrasts with commonly used PAT instruments, such as Raman or Flow‐infrared (IR), which requires a separate calibration curve for every component of the reaction mixture. To date, the large footprint of high‐field (≥400 MHz) NMR spectrometers and the immobility of superconducting magnets, coupled with strict requirements for the architecture for the room it is to be installed, have been a major obstacle to using this technology right next to fume hoods where chemists perform synthetic work. Here, we describe the use of a small, lightweight 60 MHz Benchtop NMR system (Nanalysis Pro‐60) located on a mobile platform, that was used to monitor both small and intermediate scale Grignard formation and coupling reactions. We also show how low field NMR can provide a deceptively simple yes/no answer (for a system that would otherwise require laborious off‐line testing) in the enrichment of one component versus another in a kilogram scale distillation. Benchtop NMR was also used to derive molecule specific information from Flow‐IR, a technology found in most manufacturing sites, and compare the ease at which the concentrations of the reaction mixtures can be derived by NMR versus IR. [ABSTRACT FROM AUTHOR]

C–C motif chemokine ligand 2 (CCL2) is a monocyte chemoattractant that promotes metastatic disease and portends a poor prognosis in many cancers. To determine the potential of anti-CCL2 inhibition as a therapy for recurrent metastatic disease in neuroblastoma, a mouse model of minimal residual disease was utilized in which residual disease was treated with anti-CCL2 monoclonal antibody with etoposide. The effect of anti-CCL2 antibody on neuroblastoma cells was determined in vitro with cell proliferation, transwell migration, and 2-dimensional chemotaxis migration assays. The in vivo efficacy of anti-CCL2 antibody and etoposide against neuroblastoma was assessed following resection of primary tumors formed by two cell lines or a patient-derived xenograft (PDX) in immunodeficient NOD-scid gamma mice. In vitro, anti-CCL2 antibody did not affect cell proliferation but significantly inhibited neuroblastoma cell and monocyte migration towards an increasing CCL2 concentration gradient. Treatment of mice with anti-CCL2 antibody combined with etoposide significantly increased survival of mice after resection of primary tumors, compared to untreated mice. [ABSTRACT FROM AUTHOR]

Toothed leaf margins are common (∼36%) in the New Zealand indigenous flora, and are most abundant in cool forests with high rainfall. Toothed margins are often associated with hydathodes, specialised structures that release water and solutes to maintain positive xylem pressure. However, the presence of hydathodes is mainly known from herbaceous plants. Here we investigate the presence and morphology of hydathodes in indigenous woody species representing 25 families, 33 genera and 57 species, with toothed and entire leaf margins. We tested whether toothed leaf margins on predominantly evergreen species are associated with hydathodes. Two types of structures on leaves were recognised: laminar hydathodes, water pores larger than normal stomata and associated with veins, and hydathodes positioned at the terminus of leaf teeth serviced by principal veins. Laminar hydathodes occur more frequently, but not exclusively, on toothed leaves (on 61.8% of toothed species vs. 48.0% of entire-margined species). Leaf tooth hydathodes are complex structures with undifferentiated, porous tissue plugs linked to splayed vein termini of vessel elements and often form a distinctive cap on leaf teeth. Tooth hydathodes occur on ∼90% of the serrated leaves species sampled. Ontogenetic differences in hydathode occurrence were noted in Alectryon excelsus as leaf morphology changes with plant age from a serrated to a non-serrated form. Quintinia acutifolius showed a similar pattern between individuals with different leaf morphologies. In our sampled dataset, tree species with any type of hydathode occur in areas with a higher ratio of rainfall to potential evapotranspiration than tree species without hydathodes. This pattern was not observed in shrubs. The strong association between marginal hydathodes and toothed leaves in New Zealand trees, plus the association with higher rainfall environments, suggests that these structures function to release hydraulic water pressure in plants on periodically saturated soils in high rainfall zones. [ABSTRACT FROM AUTHOR]

Evolutionary priority effects, where early-arriving lineages occupy niche space via diversification and preclude dominance of later arrivals, have been observed in alpine and forest communities. However, the potential for evolutionary priority effects to persist in an era of rapid global change remains unclear., Here, we use a natural experiment of historical disturbance in New Zealand to test whether anthropogenic changes in available habitat and nonnative invasion eliminate the role of evolutionary priority effects in community assembly. We also test whether evolutionary priority effects diminish with decreasing resource availability., Older plant clades, as estimated by clade crown age, were relatively more abundant in both primary and secondary grassland. Relative abundance in primary grassland decreased with clade stem age, but only weakly. However, for both clade age estimates, relative abundance decreased with age when nonnative biomass was high and soil moisture was low., Our data show that patterns in community structure consistent with evolutionary priority effects can occur in both primary and secondary grasslands, the latter created by anthropogenic disturbance. However, nonnative invasion may overwhelm the effect of immigration timing on community dominance, possibly as a result of high immigration rates and preadaptation to anthropogenically modified environments. [ABSTRACT FROM AUTHOR]

The cultivation of grasslands can modify both bacterial community structure and impact on nutrient cycling as well as the productivity and diversity of plant communities. In this study, two pristine New Zealand grassland sites dominated by indigenous tall tussocks (Chionochloa pallens or C. teretifolia) were examined to investigate the extent and predictability of variation of the bacterial community. The contribution of free-living bacteria to biological nitrogen fixation is predicted to be ecologically significant in these soils; therefore, the diazotrophic community was also examined. The C. teretifolia site had N-poor and poorly-drained peaty soils, and the C. pallens had N-rich and well-drained fertile soils. These soils also differ in the proportion of organic carbon (C), Olsen phosphorus (P) and soil pH. The nutrient-rich soils showed increased relative abundances of some copiotrophic bacterial taxa (including members of the Proteobacteria, Bacteroidetes and Firmicutes phyla). Other copiotrophs, Actinobacteria and the oliogotrophic Acidobacteria showed increased relative abundance in nutrient-poor soils. Greater diversity based on 16S rRNA gene sequences and the Tax4Fun prediction of enhanced spore formation associated with nutrient-rich soils could indicate increased resilience of the bacterial community. The two sites had distinct diazotrophic communities with higher diversity in C. teretifolia soils that had less available nitrate and ammonium, potentially indicating increased resilience of the diazotroph community at this site. The C. teretifolia soils had more 16S rRNA gene and nifH copies per g soil than the nutrient rich site. However, the proportion of the bacterial community that was diazotrophic was similar in the two soils. We suggest that edaphic and vegetation factors are contributing to major differences in the composition and diversity of total bacterial and diazotrophic communities at these sites. We predict the differences in the communities at the two sites will result in different responses to environmental change. [ABSTRACT FROM AUTHOR]

Aim To identify New Zealand Neogene leaf physiognomy change by comparing Miocene fossil floras to modern assemblages and assess the contributions of extinction, immigration and adaptation to leaf morphology evolution. Location New Zealand. Methods Woody angiosperm leaf assemblages were collected from modern forests throughout New Zealand and early/middle Miocene leaf assemblages (23-11 Ma) from New Zealand outcrops. All leaves were scored for 25 attributes of margin morphology, area, apex, base and general shape, and length:width ratio. Additionally, Miocene and modern Queensland leaf assemblages were compared because of their supposed climatic similarity. Results Modern New Zealand angiosperm leaves are generally smaller, and have rounder apex/base shapes than early/middle Miocene assemblages. The occurrence of leaf serrations and attenuate apices are markedly similar between modern and Miocene assemblages. Leaf size ranges of New Zealand Miocene assemblages appear to be similar to those of modern Queensland. Comparison of leaf sizes in plant families in Australia and New Caledonia with extinct and extant representatives in New Zealand, reveals that there is no consistent pattern of extinction or persistence based on leaf size. Main conclusions Late Neogene cooling in New Zealand has selected for smaller leaves with rounder apex/base shapes. Genus- and species-level extinction of broad-leaved plants contributed to leaf morphological change since the Miocene. However, it is unclear why certain broad-leaved genera persisted while others from the same family did not. The most potent drivers of late Neogene physiognomic change are the persistence, adaptation and radiation of selected pre-existing families to cooling (e.g. Rubiaceae and Ericaceae) and the arrival and diversification of cold-adapted families in the late Cenozoic (e.g. Asteraceae and Plantaginaceae). Lack of change in other characteristics, such as entire margin occurrence, suggests that these traits were not under strong selection. [ABSTRACT FROM AUTHOR]

Abiotic filters have been found either to increase or reduce evolutionary relatedness in plant communities, making it difficult to generalize responses of this major feature of biodiversity to future environmental change. Here, we hypothesized that the responses of phylogenetic structure to environmental change ultimately depend on how species have evolved traits for tolerating the resulting abiotic changes., Working within ephemeral wetlands, we tested whether species were increasingly related as flooding duration intensified. We also identified the mechanisms underlying increased relatedness by measuring root aerenchyma volume ( RAV), a trait which promotes waterlogging tolerance., We found that species-specific responses to flooding explained most of the variation in occurrence for 63 vascular plant species across 5170 plots. For a subset of 22 species, we attributed these responses to variation in RAV. Large RAV specifically increased occurrence when flooding lasted for longer time periods, because large RAV reduced above-ground biomass loss. As large RAV was evolutionarily conserved within obligate wetland species, communities were more phylogenetically related as flooding increased., Our study shows how reconstructing the evolutionary history of traits that influence the responses of species to environmental change can help to predict future patterns in phylogenetic structure. [ABSTRACT FROM AUTHOR]

Objective: Early in the COVID-19 pandemic, many children with appendicitis and COVID-19 were initially treated non-operatively and later underwent interval appendectomy. Currently, children with both appendicitis and COVID-19 frequently undergo upfront appendectomy. The impact of this return to upfront surgical management on patient outcomes is unknown. This study compared outcomes of pediatric patients with and without COVID-19 infection undergoing appendectomy. Study design: A retrospective cohort study of children < 21y who underwent appendectomy from 3/19/2020 to 7/31/2022 at 50 Pediatric Health Information System children's hospitals was conducted. Children with documented COVID-19 were identified. Exclusions included preoperative ventilator or supplemental oxygen dependence, and missing data. To evaluate COVID-19 positive versus COVID-19 negative patients, we used a propensity score matched on sociodemographics, comorbidities, laparoscopy, perforation, and hospital. Chi-square and Mann–Whitney U tests identified differences between groups in length of stay, postoperative drain placement, 30-day re-admission, and mechanical ventilation requirements. Results: Overall, 51,861 children of median age 11y (IQR: 8–14) underwent appendectomy, of whom 1,440 (2.3%) had COVID-19. Most were male (60.3%), White (72.1%) and non-Hispanic (61.4%). Public insurance was the most common (47.5%). We created a matched cohort of 1,360 COVID-19 positive and 1,360 COVID-19 negative children. Children with COVID-19 had shorter hospitalizations (1d, IQR: 1–4 vs. 2d, IQR: 1–5, p = 0.03), less postoperative peritoneal drain placement (2.4% vs. 4.1%, p = 0.01), and fewer 30-day readmissions (9.0% vs. 11.4%, p = 0.04). However, no difference in incidence or duration of mechanical ventilation (p > 0.05) was detected. Conclusions: Our findings suggest that upfront appendectomy for children with appendicitis and COVID-19 has similar outcomes compared to children without COVID-19. Level of evidence: Level III. [ABSTRACT FROM AUTHOR]

Quantitative leaf mass per area reconstructions and prevalence of plicate vernation in broad-leaved Nothofagaceae fossils reveal that deciduousness was common in the middle to late Miocene of New Zealand. This functional type was subsequently lost, as modern-day New Zealand Nothofagaceae have small leaves that live for at least a year. Moreover, fully deciduous trees across all plant families are rare in the current New Zealand flora. Based on modern-day distribution in the Southern Hemisphere, broad-leaved deciduous Nothofagaceae occupy regions with consistently large seasonal differences in precipitation and cloud cover, relative to other functional types in the family (evergreen, small-leaved). Specifically, broad-leaved deciduous Nothofagaceae are in leaf in summer when cloud cover and precipitation are low, but are leafless in winter when cloud cover and precipitation is high. Notably, the seasonal difference in precipitation and cloud cover are more important in explaining deciduousness in Nothofagaceae than winter temperatures. Therefore, potential summer photosynthetic gains likely determine deciduousness in Nothofagaceae. Miocene palaeoclimate reconstructions reveal that New Zealand broad-leaved deciduous Nothofagaceae also thrived in a climate with larger seasonal precipitation differences than today, in an overall warmer climate. We suggest that deciduous Nothofagaceae in the New Zealand flora went extinct as the global climate cooled and summer photosynthetic gains diminished, as summers became progressively rainier and cloudier, favoring an evergreen habit. • Miocene broad-leaved Nothofagaceae fossils from New Zealand were deciduous. • Deciduousness is virtually absent in the modern New Zealand flora. • Modern broad-leaved deciduous Nothofagaceae favor seasonal forests. • Miocene New Zealand climates were warmer and more seasonal. • Late Cenozoic seasonality decrease led to the loss of New Zealand deciduous forests. [ABSTRACT FROM AUTHOR]

A key hypothesis in population ecology is that synchronous and intermittent seed production, known as mast seeding, is driven by the alternating allocation of carbohydrates and mineral nutrients between growth and reproduction in different years, i.e. 'resource switching'. Such behaviour may ultimately generate bimodal distributions of long-term flower and seed production, and evidence of these patterns has been taken to support the resource switching hypothesis. Here, we show how a widely-used statistical test of bimodality applied by many studies in different ecological contexts may fail to reject the null hypothesis that focal probability distributions are unimodal. Using data from five tussock grass species in South Island, New Zealand, we find clear evidence of bimodality only when flowering patterns are analyzed with probabilistic mixture models. Mixture models provide a theory oriented framework for testing hypotheses of mast seeding patterns, enabling the different responses underlying medium- and high- versus non- and low-flowering years to be modelled more realistically by associating these with distinct probability distributions. Coupling theoretical expectations with more rigorous statistical approaches will empower ecologists to reject null hypotheses more often. [ABSTRACT FROM AUTHOR]

Plant invasions are predicted to accelerate in a world with increased anthropogenic disturbance. Non-native species pre-adapted to these disturbances may especially be poised to invade novel communities. Conservation managers therefore need predictions of how to alter disturbances to maximize the persistence of native biodiversity., We tested a multivariate hypothesis about the causal mechanisms underlying plant invasions in an ephemeral wetland in South Island, New Zealand, to inform management of this biodiverse but globally imperilled habitat. Our approach details among the first applications in ecology of Bayesian structural equation modelling, demonstrating its potential to inform management by disentangling the relative importance of strongly intercorrelated processes., We found that invasion by non-native plants was lowest in sites where the physical disturbance caused by flooding was both intense and frequent. This effect was stronger than the positive response of non-native species to high soil N supply, which was positively related to flooding., Sites flooded over a 4-year period had greater reductions in invasion than those associated with floods in the year prior to plot measurement because non-native species lacked traits for long-term persistence beneath water. Grazer exclusion had a small positive effect on invasion, as non-native species were preferentially selected by the herbivores at our site., Our results show that only species adapted to the dominant disturbance regimes at a site may become successful invaders. Species native to ephemeral wetlands have specially evolved traits that allow them to persist and dominate in these sites., Synthesis and applications. Predictions of invasions in a world of multiple disturbances clearly need to consider whether the evolutionary history of non-native species predisposes them to invade novel communities. Maintaining hydrological and nutrient regimes of ephemeral wetlands will limit the number of introduced species that are pre-adapted to become invasive. [ABSTRACT FROM AUTHOR]

Alternative stable states have long been thought to exist in natural communities, but direct evidence for their presence and for the environmental switches that cause them has been scarce. Using a combination of greenhouse and field experiments, we investigated the environmental drivers associated with two distinctive herbaceous communities in coastal ecosystems in New Zealand. In a mosaic unrelated to micro-topography, a community dominated largely by native turf species (notably Leptinella dioica, Samolus repens, and Selliera radicans) alternates with vegetation comprising exotic (i.e., nonnative) pasture species (notably Agrostis stolonifera, Holcus lanatus, Lolium perenne, and Trifolium repens). The species of these two communities differ in functional characters related to leaf longevity and growth rate, and occupy soils of differing nitrogen levels. Both spatial and environmental factors influenced the species composition locally. Reciprocal transplants of soil, with and without associated vegetation, showed that a native turf community developed when sward or soil from either community was bounded by turf, and a pasture community developed when sward or soil from either community was surrounded by pasture. In artificial mixed communities in the greenhouse, turf was able to invade the pasture community where the vegetation was clipped to simulate grazing, and also where Trifolium was removed and/or salt spray was applied. The pasture community invaded the turf where Trifolium was present or nitrogen was added. These results were supported by trends in experimentally manipulated field plots, where the amount of turf cover increased when nitrogen was kept low and when salt spray was applied, whereas pasture cover increased in the absence of salt spray. Thus, persistence of the native turf community is dependent on grazing, both directly and via its effect on keeping nitrogen levels low by excluding the exotic, nitrogen-fixing Trifolium, and by exposing the vegetation to salt spray. If any of these factors change, there could be a state change to pasture dominance that might be resistant to reversion to turf. Managing such coastal herbaceous communities therefore requires an understanding of the environmental and species characteristics that maintain alternative states. [ABSTRACT FROM AUTHOR]

Over four decades ago, Pierre Dansereau, the noted North American ecologist, proposed six features of New Zealand vegetation as being problematic or unusual in a global context. We examine his propositions in the light of current ecological knowledge to determine whether or not these can still be considered unusual characteristics of New Zealand vegetation. (1) 'Climatic change is still progressing' resulting in disequilibrium between species' distributions and the present climate. New data and methods of analysis now available have removed the impression that Dansereau gained of imprecise zonation, unclear vegetation/climate relations and missing vegetation types. Communities cited as having regeneration failure can now be seen as even-aged stands that developed after major disturbance, although there are other, also non-climatic, explanations. However, the cause of the Westland ' Nothofagus gap' has become more, rather than less, controversial. (2) 'Continuity of community composition defies classification' and 'Very few New Zealand associations have faithful species' are correct observations, but perhaps equally true of vegetation elsewhere. Dansereau's assertion of low species richness in New Zealand is not supported by the comparative data available. (3) 'Lack of intolerant [i.e. mid-seral] trees ...' is not evident with newer information. The order of species in succession, seen as unclear by Dansereau, has been determined by a range of approaches, largely confirming each other. (4) 'Discrepancies of form and function ...' in divaricate shrubs and widespread heteroblasty are still controversial, with many more explanations. Several abiotic explanations have failed to stand up to investigation. Explanations in terms of herbivory have been well supported, although the extinction of the large avian herbivores makes certainty impossible. (5) 'Incidence of hybridization ...' remains problematic. We do not know whether the incidence is unusually high, as Dansereau alleged, but the limited comparative data available suggest not. (6) The 'overwhelming ... competing power of exotics' is strongly context dependent. They are prominent in many non-forest habitats. It seems that they are drivers of the vegetation change in some habitats, yet passengers after disturbance in others. Invasions can be slow, and may still be very incomplete in some ecosystem types. Whether exotics will eventually take over in most communities, or whether the native species will 'laugh them to scorn' as Cockayne suggested, only time will tell. In conclusion, some aspects of New Zealand's vegetation seem less unusual with increased knowledge, but others remain 'problems'. [ABSTRACT FROM AUTHOR]

Synchronous and intermittent reproduction in long-lived plants, known as mast seeding, is induced by climatic cues, but the mechanism explaining variation in masting among neighboring but edaphically segregated species is unknown. Soil nutrients can enhance flowering, and thus, populations on nutrient-rich soils may require less-favorable growing temperatures to flower. We tested this hypothesis by predicting the probability of flowering in response to air temperature for five species of alpine Chionochloa grasses in South Island, New Zealand, over 37 years and relating our predictions to soil N supply (NH4+ + NO3-). Summer air temperatures better predicted flowering than spring air temperatures, which were correlated with soil N mineralization. Species on N-rich soils required lower mean temperatures to induce flowering and/or responded more consistently across a gradient of air temperatures, contributing to the higher probability of their tillers and tussocks flowering at low summer temperatures. Our results suggest that flowering primarily occurs in response to warm summer temperatures, but species on N-rich soils require less favorable growing conditions because they invest relatively less N in seeds. Thus, predicting masting requires a consideration of the interactions among climate, the internal resources of plants, and mineral nutrient uptake. [ABSTRACT FROM AUTHOR]

Summary 1. Ecological processes in mixed-species assemblages are not always an additive function of those in monocultures. In areas with high ground cover of bryophytes, renowned for their considerable water retention capacity, non-additive interactions in mixed-species cushions could play a key role in the ecosystem water economy. 2. We investigated mixture effects on external water loss in natural cushions with different species pairs of mosses and liverworts and the underlying mechanism of any non-additivity through shoot characteristics and canopy traits. 3. Species mixtures in bryophyte cushions had both additive and non-additive effects on the water economy, and these interactions were dependent on the composition of species assemblages and on plant tissue mass. Non-additivity of species mixtures was positive, resulting in the improvement of water retention. 4. Our results suggest advantages for bryophyte species to grow smaller and denser when in mixtures. They appear to alter the surface exchange area to converge in size with their neighbours, thus controlling boundary-layer properties and evaporation to reduce water loss. 5. Synthesis. A shift in bryophyte assemblages thus may influence ecohydrological processes of various ecosystems that cannot be simply predicted from the water economy of the component species when in monospecific cushions. In contrast to vascular plants, bryophytes do not compete for water but share it, and trait plasticity amongst bryophyte mixtures acts as a critical physical strategy in the community water economy. [ABSTRACT FROM AUTHOR]

Plant traits are influenced by herbivore diet selection, but little is known about how traits are affected by different types of herbivores. We related eight traits of 27 subalpine shrub species in South Island, New Zealand, to damage of these shrubs by introduced red deer (Cervus elaphus) and native invertebrate herbivores using phylogenetically explicit modeling. Deer preferentially consumed species that grew quickly, were low in foliar tannins, or had high leaf area per unit mass. However, these traits did not trade off against each other; rather, they could be related to different multivariate defense strategies. Although the proportion of leaves damaged by leaf-chewing invertebrates also increased with stem growth, invertebrates did not damage the same fast growing species as those preferred by deer. Other traits may also be important in determining herbivore preferences, as suggested by the high proportion of variation in herbivory explained by phylogeny. Last, we found that the composition of invertebrate herbivore communities was more similar among closely related shrubs, and consequently, the range of invertebrate-plant associations may change if introduced deer shift plant composition toward slow-growing species. Overall, our results demonstrate the importance of herbivore type and coevolved interactions for the adaptive significance of plant traits. [ABSTRACT FROM AUTHOR]

1. Habitat structure is an important factor influencing population dynamics and trophic organisation of terrestrial invertebrates. The phylloplane zone on vascular plant leaves is topographically complex, containing a multitude of microhabitats such as leaf hairs, lesions, and structural refugia such as domatia, which may modify interactions between resident invertebrate communities, colonisers, and subsequent trophic relationships. Leaf domatia are small indentations on the underside of leaves and are often inhabited by potentially beneficial mites and other arthropods. 2. This study investigated the relationship between domatia availability and foliar mite assemblages in contrasting habitats (native forest, plantation forest, and pasture) using a standard test plant (the endemic New Zealand shrub Coprosma lucida, J.R. & G. Forst.). 3. Diverse woody native vegetation types supported higher numbers of mite species than either plantation forest or pastoral grasses. The highest number of mite species occurred in the native forest (63%), plantation forest (38%), and pastoral grasses (25%). In the native vegetation type, experimental C. lucida leaves with domatia supported higher mite densities, greater colonisation success, and more diverse mite assemblages than those without domatia. Mite assemblages within the pastoral site were significantly different from the other two vegetation types. Only one fungivorous mite species, Orthotydeus californicus, occurred compared to five mite species in native and plantation forests. 4. This study indicated that foliar mite assemblages in native vegetation on experimental C. lucida shrubs are influenced by domatia availability, resident foliar mites, and local mite assemblages. [ABSTRACT FROM AUTHOR]

Didham et al. suggested that abiotically structured communities showing trait under-dispersion are more likely to exhibit alternative stable states than are competitively structured communities showing trait over-dispersion. We argue that the opposite is the logical expectation, and discuss implications for ecological restoration at local and regional scales. [ABSTRACT FROM AUTHOR]

Uncertainties regarding the relationships between leaf and root traits have impeded an integrated understanding of plant evolution and the efficient parameterization of ecosystem models. We measured key root and leaf traits of grasses from 77 sites in four grassland regions of the world (New Zealand, Australia, South Africa, North America). Within each region, the relationships among leaf traits paralleled those among root traits. Plants with low root or leaf N concentrations had roots or leaves with high tissue density, high lignin concentrations, low amount of mass that was soluble in a neutral detergent solution, large diameter/thickness, and were less enriched in 15N. Yet, whether comparing plants within a region or among all four regions, there was little relationship between root traits and leaf traits, except for a positive relationship between root and leaf N concentration and between root and leaf δ15N. At the global scale, factors such as soil freezing and the type of nutrient limitation appear to determine relationships among leaves and roots. C4 grasses not only had lower leaf N concentrations than C3 grasses but also lower root N concentrations. When compared at the same root N concentration, C4 grasses had greater leaf N concentrations than C3 grasses. [ABSTRACT FROM AUTHOR]

Browsing by large vertebrates has been a major force in the evolution of terrestrial plants but Holocene extinctions of the browsers have left a legacy of broken biotic partnerships. Ratite birds were the largest herbivores in several regions, such as the moas of New Zealand. Many woody plants there have a distinct form of branching, described as “divaricate”, with thin, wide angled, branches intertwining to form a tangled canopy. Divaricate branching has been interpreted as a form of protection against climate extremes or as an anachronistic defense against the extinct moas. Here we report the first experimental evidence that many of these plants are defended against extant ratite browsers. In feeding experiments on two tree species with different (heteroblastic) juvenile and adult branch morphology, emus and ostriches obtained adequate feeding rates from adult shoots but sub-maintenance feeding rates from juvenile shoots with the ratite-resistant traits. Divaricate juvenile shoots suffered 30–70% less biomass removal to the birds than adult shoots. Ratites browse by a distinctive clamping and tugging action. Structural defence traits that exploit the limitations of this feeding mode include narrow, strong, elastic branches that resist being torn off, wide branching angle (“divaricate”) that makes shoots difficult to swallow, and small, widely spaced leaves. This novel plant architectural defence has developed in at least 20% of the native woody flora of New Zealand, including 10 heteroblastic tree species that exhibit the ratite-resistant strategy until they reach ca 3 metres height. It is also a major axis of variation amongst homoblastic woody shrub species. The defences are useless against mammalian browsers that shear shoots, contributing to marked decreases in the abundances of ratite-resistant species in New Zealand after the introduction of mammals. [ABSTRACT FROM AUTHOR]

It is commonly suggested that rare plant species are poor competitors. However, the study of rarity and competitive ability has, like much of the research on rare species, been hindered by insufficient sample size, scarce use of experimental methods, and lack of comparison with common species. We used a within-taxon comparative approach to test for differences in competitive ability between rare and common species in two genera, Acaena ( Rosaceae: six rare and four common species) and Chionochloa ( Poaceae: four rare and five common species). We grew plants in replicated experiments at two levels of soil fertility and with two levels of competition, in monoculture or mixed with the introduced grass Agrostis capillaris . Competitive response was measured as relative yield, relative tiller increase, and change in live-leaf fraction. Rarity was measured by geographic range size, defined as the number of 10-km grid squares occupied by each species in New Zealand. The relationship between competitive ability and geographic range size was tested with correlations. Within Acaena , four of the rare species had high competitive ability, but there was no general relationship between competitive ability and rarity at either high or low levels of fertility. Differences in competitive ability appeared related to differences in ecological distribution rather than to rarity or commonness in a geographic sense. Within Chionochloa , common species tended to be stronger competitors than rare species, with the relationship being significant at the low level of fertility. Several of the common Chionochloa species have expanded their geographic ranges relatively recently, consistent with their greater competitive ability. Conversely, rare Chionochloa species occupy specialized habitats that may be interpreted as refuges from competition. Disparate results from Acaena and Chionochloa do not support the notion that rare species are generally poor competitors. Although rare species may... [ABSTRACT FROM AUTHOR]

Examines the interactions of irradiance and soil nutrient supply on growth seedlings of ten European tall-shrub species and Fagus sylvatica. Light demands of the plants; Response to nutrients; Shade tolerance; Average mortality in deep shade on grassland soil.

Diversification of woody plant lineages in New Zealand has unfolded in complex physiographic, climatic, and environmental contexts. Many tree and shrub lineages have existed in New Zealand since the late Cenozoic when Forest was the dominant biome, subsequently diversifying (or continuing to diversify) during the Pliocene/Pleistocene as Open (below treeline) and Alpine biomes emerged. We examine the links between biomes occupied, traits, and diversification. In particular, whether traits are phylogenetically conserved or ecologically constrained and their relationship to biomes occupied. We focus on Melicytus, Myrsine and Pseudopanax which occur across Forest, Open, and Alpine biomes. Our approach combines measured traits and modelled niche traits of extant species to examine the importance of biome occupancy and biome shifts on trait evolution in these lineages. Our results demonstrate trait values are filtered by biomes in these lineages and can predict biomes occupied. However, few biome shifts were associated with trait evolution, typically only biome shifts into extreme environments (Alpine) involved trait innovations. In addition to biomes, trait evolution can also be influenced by species age, trait lability and broad climatic change. Integrating functional traits in a phylogenetic framework can identify how evolutionary and ecological features create modern biogeographic patterns in New Zealand. [ABSTRACT FROM AUTHOR]

Biome conservatism is often regarded as common in diversifying lineages, based on the detection of low biome shift rates or high phylogenetic signal. However, many studies testing biome conservatism utilise a single-biome-per-species approach, which may influence the detection of biome conservatism. Meta-analyses show that biome shift rates are significantly lower (less than a tenth), when single biome occupancy approaches are adopted. Using New Zealand plant lineages, estimated biome shifts were also significantly lower (14–67% fewer biome shifts) when analysed under the assumption of a single biome per species. Although a single biome approach consistently resulted in lower biome shifts, it detected fewer instances of biome conservatism. A third of clades (3 out of 9) changed status in biome conservatism tests between single and multiple biome occupancy approaches, with more instances of significant biome conservatism when using a multiple biome occupancy approach. A single biome approach may change the likelihood of finding biome conservatism because it assumes biome specialisation within species, falsely recognises some biome shift types and fails to include other biome shift types. Our results indicate that the degree of biome fidelity assumed has a strong influence on analyses assessing biome shift rates, and biome conservatism testing. We advocate analyses that allow species to occupy multiple biomes. [ABSTRACT FROM AUTHOR]

Aim: To investigate species and clade biome occupancy patterns of Australian Acacia to test for within‐biome diversification, which indicate biome conservatism. Location: Australia. Taxon: Acacia (Fabaceae). Methods: Species distributions were predicted for 481 Australian Acacia using the Thornley Transport Resistance Species Distribution Model and mapped across four biome typologies. Within Acacia 19 clades were identified. The number of biomes occupied and niche size was quantified for every species and clade using the range area projected by the distribution model. Relationships between clade species richness, niche size and biomes occupied were tested using phylogenetic least squares regression models. Results: Only 9% of the Acacia 481 species and no clades were biome specialists. There were most specialist taxa in the Crisp Biome classification (8.7%), followed by WWF Biomes (6.2%), González–Orozco Biomes (5.0%) then Functional Biomes (1.2%). On average Acacia species occupied four WWF Biomes, seven Functional Biomes, three Crisp Biomes and three González–Orozco Biomes (out of 7, 13, 5 or 6 biomes respectively). Clades were also distributed across multiple biomes (2–13) with a significant positive relationship between clade species richness and the number of biomes occupied for all biome typologies. Species richness had positive linear relationships with biome area for all biome concepts except the González–Orozco Biomes. Larger clades had larger niche sizes. Main conclusions: Acacia diversification occurred across biome boundaries and was not associated with biome specialization. Species and clades mainly occurred in multiple biomes, and there were typically few biome specialists. Diversification in Acacia appears to be decoupled from biome conservatism, associated with expanding niche size across biome boundaries. Major ecological–environmental units such as biomes may constrain adaptive radiation processes via biome conservatism in many groups, but this study leads us to hypothesize that for some lineages biome boundaries are permeable. [ABSTRACT FROM AUTHOR]

Efforts to increase deceased donation have included the use of US Public Health Service (PHS) high‐risk donors. The homeless have high rates of medical and substance abuse issues that are often unrecognized. This study investigates whether the homeless should become suitable organ donors. We retrospectively reviewed 193 brain‐dead prospective donors from Hawaii's organ procurement organization (OPO; 2013‐2018) and compared two groups: homeless (n = 13) and non‐homeless (n = 180) prospective donors. The homeless prospective donors were older (48.0 vs 40.7 years, P = .009) and had more substance abuse (30.8% vs 10%, P = .046), methamphetamine use (53.8% vs 12.2%, P = .001), cocaine use (23.1% vs 3.9%, P = .022), and urine with amphetamines (54.5% vs 17.9%, P = .049). The homeless prospective donors trended toward more PHS high‐risk designation (50% vs 19%, P = .062). There was no difference in medical history, gender/race, hepatitis serologies, authorization for donation, and organs procured/transplanted between prospective donors. We have provided evidence that the homeless should become prospective organ donors; however, they have more high‐risk behaviors and often have limited information. Larger studies from OPOs are needed to better characterize organ donation and track disease transmission in this population. [ABSTRACT FROM AUTHOR]

Land cover change is a key component of anthropogenic global environmental change, contributing to changes in environmental conditions of habitats. Deforestation is globally the most widespread and anthropogenically driven land cover change leading to conversion from closed forest to open non-forest habitat. This study investigates the relative roles of geographic features, characteristics of species climatic niche and species traits in determining the ability of open-habitat plant species to take advantage of recently opened habitats. We use current occurrence records of 18 herbaceous, predominantly open-habitat species of the genus Acaena (Rosaceae) to determine their prevalence in recently opened habitat. We tested correlation of species prevalence in anthropogenically opened habitat with (i) geographic features of the spatial distribution of open habitat, (ii) characteristics of species climatic niche, and (iii) species traits related to dispersal. While primary open habitat (naturally open) was characterised by cold climates, secondary open habitat (naturally closed but anthropogenically opened) is characterised by warmer and wetter conditions. We found high levels of variation in the species prevalence in secondary open habitat indicating species differences in their ability to colonise newly opened habitat. For the species investigated, geographical features of habitat and climatic niche factors showed generally stronger relationships with species prevalence in secondary open habitat than functional traits. Therefore, for small herbaceous species, geographical features of habitat and environmental factors appear to be more important than species functional traits for facilitating expansion into secondary open habitats. Our results suggested that the land cover change might have triggered the shifts of factors controlling open-habitat plant distributions from the competition with forest trees to current environmental constraints. [ABSTRACT FROM AUTHOR]

Aim: How mountains accumulate species diversity remains poorly understood, particularly the relative role of in situ cladogenesis compared with colonization from lower elevations. Here, we estimated the contributions of in situ cladogenesis and colonization in generating biodiversity of a large mountain plant radiation and determined the importance of niche adaptation and divergence in these processes. We expected cladogenesis would accompany novel habitats formed by mountain uplift, but colonization would become more important with time as dispersal opportunities accrue. Location: New Zealand, Southern Alps. Taxon: Veronica sect. Hebe (Plantaginaceae). Methods: We estimated the most complete time‐calibrated phylogeny to date for Veronica sect. Hebe to quantify rates of in situ cladogenesis and colonization of mountain habitat based on historical biogeographical models. We used environmental niche modelling to quantify species' climate niches and estimate niche disparity and divergence over time. Results: In situ cladogenesis generated more species in the mountains than colonization from lowlands. Whereas cladogenesis slowed over time, colonization increased, especially in the alpine zone. Both adaptive ecological speciation along climate niche axes and non‐adaptive, vicariant speciation contributed to cladogenesis. However, climate niche disparity through time became saturated, suggesting competition for niche space was important. Colonization brought more divergent species into mountain niches. Main Conclusions: We suggest mountain diversity accumulates through three main stages: high cladogenesis after initial colonization, decreasing cladogenesis with increasing competition and increasing colonization after niches saturate, likely promoted by niche divergence. Combining lineage and mountain uplift trajectories, these stages provide a conceptual model to understand how diversity accumulates elsewhere. Assuming these deep‐time findings apply to anthropogenic conditions, alpine specialists could struggle to outcompete colonizers facilitated by climate change, especially from generalist clades. Considering novel competitive interactions alongside niche traits and biogeographical processes will be crucial for predicting the fate of alpine biodiversity in a changing world. [ABSTRACT FROM AUTHOR]

Shrub encroachment in grassland environments is observed in many regions worldwide. However, in New Zealand, there is no consensus on the trend and magnitude of this phenomenon, and we lack empirical data to determine what environmental variables may promote shrub invasion. Here, we present a comprehensive study evaluating shrub cover change in a tussock water catchment in eastern Otago, New Zealand. Specifically, we aim to quantify shrub cover change in the catchment between 1980 and 2015, to identify the shrub species involved and to determine the environmental variables that promote shrub cover change in the studied area. Using aerial photographic records over a 35-year period, we found a 29% increase in shrub cover (from 10.5% in 1980 to 39.5% in 2015 - a 3.8-fold increase in 35 years). According to ground truthing, this shrub expansion was mainly associated with an increase in mānuka (Leptospermum scoparium) cover. Using model selection with Akaike Information Criterion, we found that the best model explaining shrub cover change in the studied tussock catchment included multiple environmental variables. Among these, initial shrub cover and elevation negatively impacted shrub cover increase within the study area, whereas slope had a positive influence, especially on the north- and east-facing aspects. Overall, shrub cover change was mostly observed in low-elevation gullies (< 500 metres elevation) with steep slopes, where mānuka is known to have optimal growth conditions. However, further shrub cover expansion may be slow as most of the available space is now restricted to poorly drained spurs at higher elevation (> 650 metres elevation). [ABSTRACT FROM AUTHOR]

Cyathea medullaris (Cyatheaceae) is a frequent pioneer of disturbed areas (e.g. landslides) or edge environments, sometimes forming near continuous canopies. We test the hypothesis that colonisation by this species as a pioneer alters the seedling assemblage to favour more shade-tolerant broadleaved trees than that beneath another common native pioneer (Kunzea robusta, Myrtaceae) in the same landscapes. We compared vegetation and abiotic characteristics of 166 sites across the Auckland region where C. medullaris or K. robusta were abundant (≥20% basal area) along successional gradients. Using hierarchical classification and ordination, we identified distinct communities associated with the different pioneers. In the forests we consider, C. dealbata is another common understorey tree fern, which sometimes, but not always, co-occurs with C. medullaris. Cyathea medullaris / C. dealbata successions occurred on steep sites with lower annual water deficit whereas K. robusta / C. dealbata successions were located on flatter, drier sites. The prevalence of macro-charcoal in K. robusta / C. dealbata forest suggests the prominence of that community is in part an outcome of the increased importance of fire disturbance in New Zealand. Dominance of C. medullaris, with C. dealbata understoreys, influences community assembly of tree species towards dominance by shade-tolerant species, whereas seedlings of less shade-tolerant small-leaved species are more prevalent in K. robusta / C. dealbata forests. We provide evidence to suggest that, where present in early forest communities, high tree fern abundance influences the assembly of seedling communities, supporting our hypothesis. Contrary to previous suggestions, a high abundance or basal area of tree ferns on sites not historically affected by fire did not limit the establishment and growth of canopy trees including fleshy-fruited broadleaf species. [ABSTRACT FROM AUTHOR]

National scale initiatives are being attempted in New Zealand (NZ) to meet important environmental goals following land-use intensification over recent decades. Riparian restoration to filter agricultural spillover effects is currently the most widely practised mitigation measure but few studies have investigated the cumulative value of these practices at a national level. We use an applied economic land use model the benefits (GHG emissions, N leaching, P loss, sedimentation and biodiversity gain) and relevant costs (fencing, alternative stock water supplies, restoration planting and opportunity costs) of restoring riparian margins (5–50 m) on all streams in NZ flowing through current primary sector land. Extensive sensitivity analysis reveals that depending on margin width and cost assumptions, riparian margin restoration generates net benefits of between NZ$1.7 billion – $5.2 billion/yr and benefit-cost ratios ranging between 1.4 and 22.4. This suggests that even when not monetising the increase in biodiversity or components of stream ecosystem health and other benefits from planting riparian strips, the benefits to climate and freshwater are significantly greater than the implementation costs of riparian restoration. [ABSTRACT FROM AUTHOR]

All organisms must simultaneously tolerate the environment and access limiting resources if they are to persist. Approaches to understanding abiotic filtering and competitive interactions have generally been developed independently. Consequently, integrating those factors to predict species abundances and community structure remains an unresolved challenge. We introduce a new synthetic framework that models both abiotic filtering and competition by using functional traits. First, our framework estimates species carrying capacities along abiotic gradients. Second, it estimates pairwise competitive interactions as a function of species trait differences. Applied to the study of a complex wetland community, our combined approach more than doubles the explained variance of species abundances compared to a model of abiotic tolerances alone. Trait‐based integration of competitive interactions and abiotic filtering improves our ability to predict species abundances, bringing us closer to more accurate predictions of biodiversity structure in a changing world. [ABSTRACT FROM AUTHOR]

Aim Priority effects, in which the order and timing of species arrival influence community assembly, are thought to be stronger in less stressful environments, reflecting increased competition, but this hypothesis has rarely been examined over evolutionary time. Here, we test the hypothesis using an island community of alpine plants. Location Murchison Mountains, South Island, New Zealand. Methods Lineage age data for 14 monophyletic New Zealand alpine plant genera, with stem ages ranging from 2 to 17 Ma, were paired with species presence and abundance data in 261 plots, covering nearly 400 km2. The relationships between lineage age and the relative abundance and richness of focal genera across elevation (800-1620 m) and precipitation (2500-5000 mm yr−1) gradients were investigated using linear models in a Bayesian framework. Results The relative abundance of focal genera increased with lineage age, but this effect was weaker at higher elevation and precipitation, where plants are likely to have experienced more stressful conditions. The relative richness of focal genera increased at a consistent rate despite significant changes in overall richness of focal genera across both elevation and precipitation gradients. Main conclusions Our results suggest that priority effects, on a time-scale of millions of years and involving significant evolutionary change, influence community assembly, leading to increased dominance of older lineages, but that the strength of these effects may vary with environmental conditions. Environmental gradients correlated with abiotic stress, such as elevation in alpine systems, may be particularly important for predicting the strength of both ecological and evolutionary priority effects. [ABSTRACT FROM AUTHOR]

PREMISE: Recent, rapid radiations present a challenge for phylogenetic reconstruction. Fast successive speciation events typically lead to low sequence divergence and poorly resolved relationships with standard phylogenetic markers. Target sequence capture of many independent nuclear loci has the potential to improve phylogenetic resolution for rapid radiations. METHODS: Here we applied target sequence capture with 353 protein‐coding genes (Angiosperms353 bait kit) to Veronica sect. Hebe (common name hebe) to determine its utility for improving the phylogenetic resolution of rapid radiations. Veronica section Hebe originated 5–10 million years ago in New Zealand, forming a monophyletic radiation of ca 130 extant species. RESULTS: We obtained approximately 150 kbp of 353 protein‐coding exons and an additional 200 kbp of flanking noncoding sequences for each of 77 hebe and two outgroup species. When comparing coding, noncoding, and combined data sets, we found that the latter provided the best overall phylogenetic resolution. While some deep nodes in the radiation remained unresolved, our phylogeny provided broad and often improved support for subclades identified by both morphology and standard markers in previous studies. Gene‐tree discordance was nonetheless widespread, indicating that additional methods are needed to disentangle fully the history of the radiation. CONCLUSIONS: Phylogenomic target capture data sets both increase phylogenetic signal and deliver new insights into the complex evolutionary history of rapid radiations as compared with traditional markers. Improving methods to resolve remaining discordance among loci from target sequence capture is now important to facilitate the further study of rapid radiations. [ABSTRACT FROM AUTHOR]

Bryophytes are widespread in terrestrial ecosystems but little is known about their influence on vascular species. Watersoluble leachates (0%, 1%, 5%, 10% concentration) derived from 18 species of bryophytes (mosses 11 species; liverworts 7 species) were tested on the germination and seedling growth of Lactuca sativa and two common trees Melicytus ramiflorus (Violaceae) and Fuchsia excorticata (Onagraceae) in southern New Zealand forests. Bryophyte water soluble extracts (BWSE) have minor impact on seed germination of Lactuca, stimulatory effects on radical growth at low (1%) concentrations and inhibitory effects at higher concentrations (5 - 10%). For Melicytus the BWSE had variable effects, with evidence of strong stimulatory (Dendrohypopterygium filiculiforme) and inhibitory (Lepidozia concinna) effects on germination, but generally inhibited radical growth. BWSE at all test concentrations consistently inhibit both germination and seedling radicle growth in Fuchsia. Th e toxicity effect of water-soluble leachates varies significantly between bryophyte species but not consistently between mosses and liverworts. Bryophyte species exhibiting strongest inhibition effects under control conditions were associated with significantly reduced densities of broadleaved tree seedlings in forest ecosystems. Our results demonstrate that some bryophyte species via allelopathic interactions can inhibit seedling establishment and growth of forest trees. Th is mechanism provides an additional factor constraining the spatial distribution of the regeneration niche in forest communities. [ABSTRACT FROM AUTHOR]

Plant-based defence mutualisms utilize plant morphology to reduce the performance of plant parasites through their natural enemies. Leaf domatia primarily occur in the axials of secondary veins and are often inhabited by microbivorous and predaceous mites which often increase plant growth rates and reproductive success by controlling plant pests. Our study investigated if domatia investment is limited by plant primary productivity. To our knowledge no studies have tested if foliar domatia are resource-limited. We tested our hypothesis using the genus Coprosma (Rubiaceae), conducting correlative field surveys and manipulative experiments measuring domatia production in new leaves along temperature, nutrient and irradiance gradients. Field surveys indicated a strong positive association between leaf area, the number of secondary veins, and domatia per leaf. The number of potential sites for domatia is underutilised, with leaves on selected Coprosma species having on average 47 to 72% of the 'maximum' number of available sites where domatia could occur. Foliar carbon was positively associated with domatia investment. Coprosma plants held under elevated night-time temperatures showed a 34-91% decrease in daily carbon gain, a 38% decrease in domatia per leaf mass, and a positive relationship between domatia investment and integrated daily carbon gain. Under irradiance and nutrient stress, our data indicated evidence of a positive relationship between domatia investment and foliar carbon. We found a significant negative association between relative investment in domatia produced and investment in new leaf biomass. Our findings suggest investment in foliar domatia is limited by primary productivity. We propose that domatia are discretionary goods and not intrinsic structures produced automatically on leaves that mites utilize. We suggest that plants have the ability to regulate domatia formation during leaf ontogeny, with investment controlled by resource availability and some intrinsic allocation mechanism to defence. [ABSTRACT FROM AUTHOR]

1. Prominent theories of plant defence have predicted that plants growing on nutrient-poor soils produce more phenolic defence compounds than those on richer soils. Only recently has the Protein Competition Model (PCM) of phenolic allocation suggested that N and P limitation could have different effects because the nutrients are involved in different cellular metabolic processes. 2. We extend the prediction of the PCM and hypothesize that N will have a greater influence on the production of phenolic defensive compounds than P availability, because N limitation reduces protein production and thus competition for phenylalanine, a precursor of many phenolic compounds. In contrast, P acts as a recyclable cofactor in these reactions, allowing protein and hence phenolic production to continue under low P conditions. 3. We test this hypothesis by comparing the foliar concentrations of phenolic compounds in (i) phenotypes of 21 species growing on P-rich alluvial terraces and P-depleted marine terraces in southern New Zealand, and (ii) 87 species growing under similar climates on comparatively P-rich soils in New Zealand vs. P-depleted soils in Tasmania. 4. Foliar P concentrations of plants from the marine terraces were about half those of plants from alluvial soils, and much lower in Tasmania than in New Zealand. However, foliar concentrations of N and phenolic compounds were similar across sites in both comparisons, supporting the hypothesis that N availability is a more important determinant of plant investment in phenolic defensive compounds than P availability. We found no indication that reduced soil P levels influenced plant concentrations of phenolic compounds. There was wide variation in the foliar N and P concentrations among species, and those with low foliar nutrient concentrations produced more phenolics (including condensed tannins). 5. Our study is the first trait comparison extending beyond standard leaf economics to include secondary metabolites related to defence in forest plants, and emphasizes that N and P have different influences on the production of phenolic defence compounds. [ABSTRACT FROM AUTHOR]

Aim We test hypotheses regarding the origin of diversity and patterns of species richness in and around the New Zealand Southern Alps with 25 species of Chionochloa (Poaceae, Danthonioideae). Location New Zealand. Methods We inferred a well-resolved and mostly robustly supported chloroplast phylogeny based on multiple DNA sequence markers ( trnT–L–F, rpl16, trnD–psbM, atpB–rbcL, matK and ndhF), sampling 92% of the recognized species and 82% of the subspecific taxa. Nuclear ribosomal internal transcribed spacer sequences were also sampled, but proved uninformative. Biogeographic reconstruction and character optimization were done using both parsimony and likelihood approaches, and molecular dating used relaxed clock approaches. Results Most of the species diversity in Chionochloa stemmed from a common ancestor in the southern South Island with subsequent dispersal between areas. One clade of apparently cryptic taxa diversified within the central South Island ‘endemism gap’, persisting there throughout at least the latter half of the Pleistocene. Exclusively alpine and other habitat specialist species originated independently, the former relatively recently (between 7.6 Ma and the present). Main conclusions The phylogeny of Chionochloa and other published phylogenies of New Zealand plant groups demonstrate that the higher degree of endemism in the north and south of the New Zealand South Island relative to a central endemism gap cannot be explained by Alpine Fault displacement. Furthermore, our results suggest that if extinctions resulting from glaciations played a role in the origin of the central endemism gap, their impact was less than might be presumed on the basis of the distribution of taxa as they are currently defined. The diversification of Chionochloa and a number of New Zealand plant groups, such as Ranunculus, was contemporaneous with the initiation of the uplift of the Southern Alps. In contrast to patterns of diversifications within the alpine regions typical of the hyperdiverse Andes, exclusively alpine species in New Zealand arose independently from ancestors distributed in more lowland areas. Similarly, habitat specialists in Chionochloa arose independently from more generalist ancestors. Thus, although diversification in these groups may have been stimulated by mountain building and Pleistocene climatic oscillations, cladogenesis did not occur within the high alpine habitat itself. [ABSTRACT FROM AUTHOR]

1. Ungulates have reached such high densities in some natural ecosystems that culling is frequently used to reduce their impacts on vegetation. However, much is still unknown about the outcomes of landscape-level control, in part because monitoring vegetation recovery requires decades. 2. We report long-term vegetation changes in permanent plots located in forest, shrubland and grassland communities across a mountain range in southern New Zealand. We test whether c. 92% reduction in the population of invasive non-indigenous red deer Cervus elaphus since 1964 has led to the recovery of deer-preferred species. 3. Tree seedlings, saplings and the number of seedlings per adult tree increased over time. There was lower recruitment, however, of highly palatable forest species compared with less palatable species, and the recruitment of saplings was lower in browsed forest plots compared with deer exclosures. 4. The total number of occurrences and absolute number of palatable species per plot increased over time in shrublands and grasslands respectively. The height of both shrublands and palatable grassland snow tussocks Chionochloa spp. increased, although the occurrences of most individual species remained unchanged over time. 5. Vegetation recovery at our site in response to long-term and significant herbivore reductions may be limited by several factors, including the slow growth rates of New Zealand species, density-dependent diet switching by deer, altered successional trajectories and below-ground processes. 6. Synthesis and applications. Our results suggest that after nearly four decades, even low densities of introduced herbivores may restrict ecosystem recovery, and therefore, restoring herbivore-disturbed ecosystems by solely manipulating herbivore population numbers may require a long-term perspective. Management strategies can accelerate recovery by protecting existing palatable plants within deer-exclosures, and planting or seeding palatable species within these refugia. However, in addition to increasing seed sources, restoration may only become apparent following large-scale disturbance events and canopy turnover. [ABSTRACT FROM AUTHOR]