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Background: Exposure to standard petrodiesel exhaust is linked to adverse health effects. Moreover, there is a mounting request to replace fossil-based fuels with renewable and sustainable alternatives and, therefore, rapeseed methyl ester (RME) and other biofuels have been introduced. However, recent toxicological research has indicated that biodiesel exhaust may also induce adverse health-related events., Aim: To determine whether exposure to 100% RME biodiesel (BD100) exhaust would cause an acute airway neutrophilic recruitment in humans., Methods: Fourteen healthy subjects underwent exposure to diluted BD100 exhaust and filtered air for 1-h, in a blinded, random fashion. Bronchoscopy with endobronchial mucosal biopsies, bronchial wash (BW) and bronchoalveolar lavage (BAL) was performed six hours after exposure. Differential cell counts and inflammatory markers were determined in the supernatant and biopsies were stained immunohistochemically., Results: Compared with filtered air, BD100 exhaust exposure increased bronchial mucosal endothelial P-selectin adhesion molecule expression, as well as neutrophil, mast cell and CD68 + macrophage numbers. An increased influx of neutrophils and machrophages was also seen in BW., Conclusion: Exposure to biodiesel exhaust was associated with an acute airway inflammation that appeared similar to preceding petrodiesel exposure studies. The present findings, together with the recently reported adverse cardiovascular effects after similar biodiesel exposure, indicate that biodiesel is not free of toxicity and may affect human health., Competing Interests: Declarations. Ethics approval and consent to participate: The study was performed according to the Helsinki declaration and approved at the local ethics committee at Umeå university. All participants gave their written informed consent to participate. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Divergent patterns of phenotypic selection on floral traits can arise in response to interactions with functionally distinct pollinators. However, there are a limited number of studies that relate patterns of phenotypic selection on floral traits to variation in local pollinator assemblages in pollination-generalized plant species. We studied phenotypic selection on floral traits of Viscaria vulgaris, a plant that interacts with a broad range of diurnal and nocturnal pollinators, and related divergence in phenotypic selection on floral traits to the expected level of divergence in local pollinator assemblages. We detected phenotypic selection on floral traits involved in the attraction of pollinators and the mechanics of pollen removal and deposition, and demonstrated that floral traits are subject to spatiotemporal variation in the strength and direction of phenotypic selection. We revealed that diurnal and nocturnal pollinators, when considered in isolation, mediated divergent patterns of phenotypic selection on floral traits. Consistent with the Grant-Stebbins model, we observed that divergence in phenotypic selection on floral traits increased with the expected level of divergence in local pollinator assemblages. Thus, generalized plant-pollinator interactions can mediate phenotypic selection on floral traits, and distinct local pollinator assemblages can generate a geographic mosaic of divergent patterns of phenotypic selection. We underscore that these outcomes are not exclusive to specialized plant-pollinator interactions and can emerge at a local geographic scale., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Evolutionary Biology.)

Diversification of plant chemical phenotypes is typically associated with spatially and temporally variable plant-insect interactions. Floral scent is often assumed to be the target of pollinator-mediated selection, whereas foliar compounds are considered targets of antagonist-mediated selection. However, floral and vegetative phytochemicals can be biosynthetically linked and may thus evolve as integrated phenotypes. Utilizing a common garden of 28 populations of the perennial herb Arabis alpina (Brassicaceae), we investigated integration within and among floral scent compounds and foliar defense compounds (both volatile compounds and tissue-bound glucosinolates). Within floral scent volatiles, foliar volatile compounds, and glucosinolates, phytochemicals were often positively correlated, and correlations were stronger within these groups than between them. Thus, we found no evidence of integration between compound groups indicating that these are free to evolve independently. Relative to self-compatible populations, self-incompatible populations experienced stronger correlations between floral scent compounds, and a trend toward lower integration between floral scent and foliar volatiles. Our study serves as a rare test of integration of multiple, physiologically related plant traits that each are potential targets of insect-mediated selection. Our results suggest that independent evolutionary forces are likely to diversify different axes of plant chemistry without major constraints., (© 2024 The Author(s). New Phytologist © 2024 New Phytologist Foundation.)

Objective: To achieve resilience in the response of a major incident, it is essential to coordinate major processes and resources with the aim to manage expected and unexpected changes. The coordination is partly done through timely, adequate, and resilience-oriented decisions. Accordingly, the aim of the present paper is to describe factors that affected decision-making in a medical command and control team during the early COVID-19 pandemic., Methods: This study used a qualitative method in which 13 individuals from a regional public healthcare system involved in COVID-19 related command and control were interviewed. Data was collected through semi-structured interviews and analyzed using qualitative content analysis., Results: The factors affecting decision-making in medical command and control during early COVID-19 pandemic were grouped into 5 themes: organization, adaptation, making decisions, and analysis, as well as common operational picture., Conclusions: The present study indicated that decision-making in medical command and control faces many challenges in the response to pandemics. The results may provide knowledge about disaster resilience and can be utilized in educational and training settings for medical command and control.

Objectives: The efficacy and safety of macitentan, an endothelin receptor antagonist, were assessed in a 52-week, prospective, multicenter, double-blind, randomized, placebo-controlled, parallel-group study assessing the efficacy and safety of macitentan in Fontan-palliated adult and adolescent patients (RUBATO-DB) and an open-label extension trial (RUBATO-OL)., Methods: Patients aged 12 years and older with New York Heart Association functional class II or III underwent total cavopulmonary connection more than 1 year before screening and showed no signs of Fontan failure/clinical deterioration. In RUBATO-DB, the primary efficacy end point was change in peak oxygen consumption from baseline to week 16; secondary end points were change from baseline over 52 weeks in peak oxygen consumption and change in mean count/minute of daily physical activity via accelerometer from baseline to week 16. Safety was assessed throughout both studies., Results: In RUBATO-DB, 137 patients were randomized to macitentan 10 mg (n = 68) or placebo (n = 69); 92.7% completed 52-week double-blind treatment. At week 16, mean ± SD change in peak oxygen consumption was -0.16 ± 2.86 versus -0.67 ± 2.66 mL/kg/minute with macitentan versus placebo (median unbiased treatment difference estimate, 0.62 mL/kg/minute [99% repeated CI, -0.62 to 1.85]; P = .19). No treatment effect was observed in either of the secondary end points. During RUBATO-DB, most common adverse events with macitentan were headache, nasopharyngitis, and pyrexia. Across RUBATO-DB and RUBATO-OL, most common adverse events were COVID-19, headache, and fatigue. RUBATO-OL was prematurely discontinued because RUBATO-DB did not meet its primary or secondary end point., Conclusions: The primary end point of RUBATO-DB was not met; macitentan did not improve exercise capacity versus placebo in patients with Fontan palliation. Macitentan was generally well tolerated over long-term treatment., Competing Interests: Conflict of Interest Statement Ms Efficace and Drs Freiberg and Haberle are employees and shareholders of Johnson & Johnson. Ms Walter is a contractor of Johnson & Johnson. Drs Clift, Berger, Sondergaard, and d’Udekem received consulting fees from Johnson & Johnson. Dr Sondergaard is currently chief medical officer and divisional vice president at Abbott Structural Heart. Dr Nicolarsen received consulting fees from Medtronic, accommodation support for attending meetings from the Adult Congenital Heart Association, and served as a board member for Adult Congenital Heart Association and Alliance for Adult Research in Congenital Cardiology. All other authors reported no conflicts of interest. The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: A substantial proportion of individuals with COPD have never smoked, and it is implied to be more common than previously anticipated but poorly studied., Aim: To describe the process of recruitment of never-smokers with COPD from a population-based cohort ( n  = 30 154)., Methods: We recruited never-smokers with COPD, aged 50-75 years, from six University Hospitals, based on: 1) post broncho-dilator forced expiratory volume in 1 second/forced vital capacity (FEV 1 /FVC) < 0.70 and 2) FEV 1 50-100% of predicted value and 3) being never-smokers (self-reported). In total 862 SCAPIS participants were identified, of which 652 were reachable and agreed to a first screening by telephone. Altogether 128 (20%) were excluded due to previous smoking or declined participation. We also applied a lower limit of normal (LLN) of FEV 1 /FVC (z-score<-1.64) according to the Global Lung Initiative to ensure a stricter definition of airflow obstruction., Results: Data on respiratory symptoms, health status, and medical history were collected from 492 individuals, since 32 were excluded at a second data review (declined or previous smoking), prior to the first visit. Due to not matching the required lung function criteria at a second spirometry, an additional 334 (68%) were excluded. These exclusions were by reason of: FEV 1 /FVC ≥0.7 (49%), FEV 1 > 100% of predicted (26%) or z-score ≥ -1,64 (24%). Finally, 154 never-smokers with COPD were included: 56 (36%) women, (mean) age 60 years, FEV 1 84% of predicted, FEV 1 /FVC: 0.6, z-score: -2.2, Oxygen saturation: 97% and BMI: 26.8 kg/m 2 ., Conclusions: The challenges of a recruitment process of never-smokers with COPD were shown, including the importance of correct spirometry testing and strict inclusion criteria. Our findings highlight the importance of repeated spirometry assessments for improved accuracy in diagnosing COPD., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

Environmental change is disrupting mutualisms between organisms worldwide. Reported declines in insect populations and changes in pollinator community compositions in response to land use and other environmental drivers have put the spotlight on the need to conserve pollinators. While this is often motivated by their role in supporting crop yields, the role of pollinators for reproduction and resulting taxonomic and functional assembly in wild plant communities has received less attention. Recent findings suggest that observed and experimental gradients in pollinator availability can affect plant community composition, but we know little about when such shifts are to be expected, or the impact they have on ecosystem functioning. Correlations between plant traits related to pollination and plant traits related to other important ecosystem functions, such as productivity, nitrogen uptake or palatability to herbivores, lead us to expect non-random shifts in ecosystem functioning in response to changes in pollinator communities. At the same time, ecological and evolutionary processes may counteract these effects of pollinator declines, limiting changes in plant community composition, and in ecosystem functioning. Despite calls to investigate community- and ecosystem-level impacts of reduced pollination, the study of pollinator effects on plants has largely been confined to impacts on plant individuals or single-species populations. With this review we aim to break new ground by bringing together aspects of landscape ecology, ecological and evolutionary plant-insect interactions, and biodiversity-ecosystem functioning research, to generate new ideas and hypotheses about the ecosystem-level consequences of pollinator declines in response to land-use change, using grasslands as a focal system. Based on an integrated set of seven hypotheses, we call for more research investigating the putative pollinator-mediated links between landscape-scale land use and ecosystem functioning. In particular, future research should use combinations of experimental and observational approaches to assess the effects of changes in pollinator communities over multiple years and across species on plant communities and on trait distributions both within and among species., (© 2023 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.)

Agricultural intensification at field and landscape scales, including increased use of agrochemicals and loss of semi-natural habitats, is a major driver of insect declines and other community changes. Efforts to understand and mitigate these effects have traditionally focused on ecological responses. At the same time, adaptations to pesticide use and habitat fragmentation in both insects and flowering plants show the potential for rapid evolution. Yet we lack an understanding of how such evolutionary responses may propagate within and between trophic levels with ensuing consequences for conservation of species and ecological functions in agroecosystems. Here, we review the literature on the consequences of agricultural intensification on plant and animal evolutionary responses and interactions. We present a novel conceptualization of evolutionary change induced by agricultural intensification at field and landscape scales and emphasize direct and indirect effects of rapid evolution on ecosystem services. We exemplify by focusing on economically and ecologically important interactions between plants and pollinators. We showcase available eco-evolutionary theory and plant-pollinator modelling that can improve predictions of how agricultural intensification affects interaction networks, and highlight available genetic and trait-focused methodological approaches. Specifically, we focus on how spatial genetic structure affects the probability of propagated responses, and how the structure of interaction networks modulates effects of evolutionary change in individual species. Thereby, we highlight how combined trait-based eco-evolutionary modelling, functionally explicit quantitative genetics, and genomic analyses may shed light on conditions where evolutionary responses impact important ecosystem services., (© 2023 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.)

Background: According to shortage of registered nurses, organisational and leadership aspects grounded in person-centrered approach, are highlighted to ensure high quality of care. Therefore, it is interesting to develop knowledge regarding registered nurses working environment., Aim: The aim of the study was to investigate registered nurses' reason to end their employment at a university hospital setting (internal medicine, emergency department)., Method: Qualitative content analysis with an inductive methodological approach was used to analyse registered nurses' experiences regarding their former employment. Inclusion criteria; all nurses (n = 55) who ended employment during one year (first of July 2020-30th of June 2021) were invited, and 38 semi-structured interviews were conducted., Results: Three categories were identified: Limited organisational support, Lack of visible leadership, and Limited healthy working environment, followed by six subcategories: Longing for organisational support, Being a tile in a box, Need for professional relationship, Limitation of supportive leadership, Imbalance of work versus personal life, and Ethical stress., Conclusion: To improve registered nurses working environment and commitment to work, balance between time at work and personal life is significant. Therefore, organisational support and leadership skills grounded in a person-centred approach are crucial to develop a healthy working environment. A person-centred leadership could improve collaboration and shared decision-making in partnership with those involved, managers, nurses, and team members., (© 2024. The Author(s).)

Introduction: Menstrual cups (MC) are a reusable feminine hygiene product. A recent publication suggested that Staphylococcus aureus ( S. aureus ) biofilms can form on MCs which may lead to increased risk of menstrual Toxic Shock Syndrome (mTSS). Additionally, there is concern that buildup of residual menses may contribute to microbial growth and biofilm formation further increasing mTSS risk. Quantitative and qualitative analysis of in vitro tests were utilized to determine if S. aureus biofilm could form on MC in the presence of the keystone species Lactobacillus after 12 h of incubation. The methodology was based on a modification of an anaerobic in vitro method that harnesses the keystone species hypothesis by including a representative of vaginal lactic acid bacteria., Methods: MCs were incubated anaerobically for 12 h in Vaginal Defined Media (VDM) with the two morphologically distinct bacteria, Lactobacillus gasseri ( L. gasseri ) and S. aureus . Colony Forming Units (CFU) for each organism from the VDM broth and sonicated MC were estimated. In addition, a separate experiment was conducted where S. aureus was grown for 12 h in the absence of L. gasseri . Qualitative analysis for biofilm formation utilized micro-CT (µ-CT) and cryogenic scanning electron microscopy (Cryo-SEM)., Results: Samples collected from the media control had expected growth of both organisms after 12 h of incubation. Samples collected from VDM broth were similar to media control at the end of the 12-h study. Total S. aureus cell density on MC following sonication/rinsing was minimal. Results when using a monoculture of S. aureus demonstrated that there was a significant growth of the organism in the media control and broth as well as the sonicated cups indicating that the presence of L. gasseri was important for controlling growth and adherence of S. aureus . Few rod-shaped bacteria ( L. gasseri) and cocci ( S. aureus) could be identified on the MCs when grown in a dual species culture inoculum and no biofilm was noted via µ-CT and cryo-SEM. Additionally, efforts to model and understand the validity of the current labeled recommendations for MC cleaning in-between uses are supported., Discussion: The data support continued safe use of the Tampax® cup when used and maintained as recommended., Competing Interests: All authors are current or retired employees of The Procter & Gamble Company., (© 2023 Friberg, Woeller, Iberi, Mancheno, Riedeman, Bohman and Davis.)

Reserve starch from seeds and tubers is a crucial plant product for human survival. Much research has been devoted to quantitative and qualitative aspects of starch synthesis and its relation to abiotic factors of importance in agriculture. Certain aspects of genetic factors and enzymes influencing carbon assimilation into starch granules remain elusive after many decades of research. Starch phosphorylase (Pho) can operate, depending on metabolic conditions, in a synthetic and degradative pathway. The plastidial form of the enzyme is one of the most highly expressed genes in potato tubers, and the encoded product is imported into starch-synthesizing amyloplasts. We identified that the genomic locus of a Pho1a-type starch phosphorylase is duplicated in potato. Our study further shows that the enzyme is of importance for a normal starch granule phenotype in tubers. Null mutants created by genome editing display rounded starch granules in an increased number that contained a reduced ratio of apparent amylose in the starch., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Sharma, Friberg, Vogel, Turesson, Olsson, Andersson and Hofvander.)

Background: Exposure to wood smoke has been shown to contribute to adverse respiratory health effects including airway infections, but the underlying mechanisms are unclear. A preceding study failed to confirm any acute inflammation or cell influx in bronchial wash (BW) or bronchoalveolar lavage (BAL) 24 h after wood smoke exposure but showed unexpected reductions in leukocyte numbers. The present study was performed to investigate responses at an earlier phase, regarding potential development of acute inflammation, as well as indications of cytotoxicity., Methods: In a double-blind, randomised crossover study, 14 healthy participants were exposed for 2 h to filtered air and diluted wood smoke from incomplete wood log combustion in a common wood stove with a mean particulate matter concentration of 409 µg/m 3 . Bronchoscopy with BW and BAL was performed 6 h after exposure. Differential cell counts, assessment of DNA-damage and ex vivo analysis of phagocytic function of phagocytosing BAL cells were performed. Wood smoke particles were also collected for in vitro toxicological analyses using bronchial epithelial cells (BEAS-2B) and alveolar type II-like cells (A549)., Results: Exposure to wood smoke increased BAL lactate dehydrogenase (LDH) (p = 0.04) and reduced the ex vivo alveolar macrophage phagocytic capacity (p = 0.03) and viability (p = 0.02) vs. filtered air. BAL eosinophil numbers were increased after wood smoke (p = 0.02), while other cell types were unaffected in BW and BAL. In vitro exposure to wood smoke particles confirmed increased DNA-damage, decreased metabolic activity and cell cycle disturbances., Conclusions: Exposure to wood smoke from incomplete combustion did not induce any acute airway inflammatory cell influx at 6 h, apart from eosinophils. However, there were indications of a cytotoxic reaction with increased LDH, reduced cell viability and impaired alveolar macrophage phagocytic capacity. These findings are in accordance with earlier bronchoscopy findings at 24 h and may provide evidence for the increased susceptibility to infections by biomass smoke exposure, reported in population-based studies., (© 2023. The Author(s).)

Selection leading to adaptation to interactions may generate rapid evolutionary feedbacks and drive diversification of species interactions. The challenge is to understand how the many traits of interacting species combine to shape local adaptation in ways directly or indirectly resulting in diversification. We used the well-studied interactions between Lithophragma plants (Saxifragaceae) and Greya moths (Prodoxidae) to evaluate how plants and moths together contributed to local divergence in pollination efficacy. Specifically, we studied L. bolanderi and its two specialized Greya moth pollinators in two contrasting environments in the Sierra Nevada in California. Both moths pollinate L. bolanderi during nectaring, one of them-G. politella-also while ovipositing through the floral corolla into the ovary. First, field surveys of floral visitors and the presence of G. politella eggs and larvae in developing capsules showed that one population was visited only by G. politella and few other pollinators, whereas the other was visited by both Greya species and other pollinators. Second, L. bolanderi in these two natural populations differed in several floral traits putatively important for pollination efficacy. Third, laboratory experiments with greenhouse-grown plants and field-collected moths showed that L. bolanderi was more efficiently pollinated by local compared to nonlocal nectaring moths of both species. Pollination efficacy of ovipositing G. politella was also higher for local moths for the L. bolanderi population, which relies more heavily on this species in nature. Finally, time-lapse photography in the laboratory showed that G. politella from different populations differed in oviposition behavior, suggesting the potential for local adaptation also among Greya populations. Collectively, our results are a rare example of components of local adaptation contributing to divergence in pollination efficacy in a coevolving interaction and, thus, provide insights into how geographic mosaics of coevolution may lead to coevolutionary diversification in species interactions., (© 2023 The Authors. Ecology published by Wiley Periodicals LLC on behalf of The Ecological Society of America.)

Premise: The role of pollinators in evolutionary floral divergence has spurred substantial effort into measuring pollinator-mediated phenotypic selection and its variation in space and time. For such estimates, the fitness consequences of pollination processes must be separated from other factors affecting fitness., Methods: We built a fitness function linking phenotypic traits of food-deceptive orchids to female reproductive success by including pollinator visitation and pollen deposition as intermediate performance components and used the fitness function to estimate the strength of pollinator-mediated selection through female reproductive success. We also quantified male performance as pollinarium removal and assessed similarity in trait effects on male and female performance., Results: The proportion of plants visited at least once by an effective pollinator was moderate to high, ranging from 53.7% to 85.1%. Tall, many-flowered plants were often more likely to be visited and pollinated. Given effective pollination, pollen deposition onto stigmas tended to be more likely for taller plants. Pollen deposition further depended on traits affecting the physical fit of pollinators to flowers (flower size, spur length), though the exact relationships varied in time and space. Using the fitness function to assess pollinator-mediated selection through female reproductive success acting on multiple traits, we found that selection varied detectably among taxa after accounting for sampling uncertainty. Across taxa, selection on most traits was stronger on average and more variable when pollination was less reliable., Conclusions: These results support pollination-related trait-performance-fitness relationships and thus pollinator-mediated selection on traits functionally involved in the pollination process., (© 2023 The Authors. American Journal of Botany published by Wiley Periodicals LLC on behalf of Botanical Society of America.)

Objective: The purpose of this study was to compare laypeople's and professional first responders' ability to perform tourniquet application and cardiopulmonary resuscitation (CPR) during calm and stressful circumstances., Background: Life-threatening bleeding is a major cause of death that could be prevented by fast and appropriate first aid interventions. Therefore, laypeople are now being trained in bleeding control skills, transforming them from bystanders to immediate responders. However, critics have questioned whether laypeople are able to perform during more stressful conditions., Method: Twenty-four laypersons and 31 professional first responders were tested in two conditions: a calm classroom scenario and a stressful scenario consisting of paintball fire and physical exertion. Stress and workload were assessed along with task performance., Results: The experimental manipulation was successful in terms of eliciting stress reactions. Tourniquet application performance did not decline in the stressful condition, but some aspects of CPR performance did for both groups. First responders experienced higher task engagement and lower distress, worry and workload than the laypeople in both the calm and stressful conditions., Conclusion: Stress did not affect first responders and laypeople differently in terms of performance effects. Stress should therefore not be considered a major obstacle for teaching bleeding control skills to laypeople., Application: Tourniquet application can be taught to laypeople in a short amount of time, and they can perform this skill during stress in controlled settings. Concerns about laypeople's ability to perform under stress should not exclude bleeding control skills from first aid courses for civilian laypeople.

Mating system shifts from outcrossing to selfing are frequent in plant evolution. Relative to outcrossing, selfing is associated with reduced parental conflict over seed provisioning, which may result in postzygotic, asymmetric, reproductive isolation in crosses between populations of different mating systems. To test the hypothesis that post-pollination reproductive isolation between populations increases with increasing differences in mating system and predicted parental conflict, we performed a crossing experiment involving all combinations of three self-compatible populations (with low outcrossing rates), and three self-incompatible populations (with high outcrossing rates) of the arctic-alpine herb Arabis alpina, assessing fitness-related seed and plant traits of the progeny. Predicted levels of parental conflict ("genome strength") were quantified based on strength of self-incompatibility and estimates of outcrossing rates. Crosses between self-compatible and self-incompatible populations yielded very small seeds of low viability, resulting in strong reproductive isolation. In 14 of 15 reciprocal between-population crosses, seeds were heavier when the paternal plant had the stronger genome, and seed mass differences between cross directions increased with an increased difference in parental conflict. Overall, our results suggest that, when sufficiently large, differences in mating system and hence in expected parental conflict may result in strong post-pollination reproductive barriers contributing to speciation., (© The Author(s) 2023. Published by Oxford University Press on behalf of The Society for the Study of Evolution (SSE).)

Natural selection on floral scent composition is a key element of the hypothesis that pollinators and other floral visitors drive scent evolution. The measure of such selection is complicated by the high-dimensional nature of floral scent data and uncertainty about the cognitive processes involved in scent-mediated communication. We use dimension reduction through reduced-rank regression to jointly estimate a scent composite trait under selection and the strength of selection acting on this trait. To assess and compare variation in selection on scent across species, time and space, we reanalyse 22 datasets on six species from four previous studies. The results agreed qualitatively with previous analyses in terms of identifying populations and scent compounds subject to stronger selection but also allowed us to evaluate and compare the strength of selection on scent across studies. Doing so revealed that selection on floral scent was highly variable, and overall about as common and as strong as selection on other phenotypic traits involved in pollinator attraction or pollen transfer. These results are consistent with an important role of floral scent in pollinator attraction. Our approach should be useful for further studies of plant-animal communication and for studies of selection on other high-dimensional phenotypes. In particular, our approach will be useful for studies of pollinator-mediated selection on complex scent blends comprising many volatiles, and when no prior information on the physiological responses of pollinators to scent compounds is available., (© 2022 The Authors. Journal of Evolutionary Biology published by John Wiley & Sons Ltd on behalf of European Society for Evolutionary Biology.)

Pollinator sharing between close relatives can be costly and can promote pollination niche partitioning and floral divergence. This should be reflected by a higher species divergence in sympatry than in allopatry. We tested this hypothesis in two orchid congeners with overlapping distributions and flowering times. We characterized floral traits and pollination niches and quantified pollen limitation in 15 pure and mixed populations, and we measured phenotypic selection on floral traits and performed controlled crosses in one mixed site. Most floral traits differed between species, yet pollinator sharing was extensive. Only the timing of scent emission diverged more in mixed sites than in pure sites, and this was not mirrored by the timing of pollinator visitation. We did not detect divergent selection on floral traits. Seed production was pollen limited in most populations but not more severely in mixed sites than in pure sites. Interspecific crosses produced the same or a higher proportion of viable seeds than intraspecific crosses. The two orchid species attract the same pollinator species despite showing divergent floral traits. However, this does not promote character displacement, implying a low cost of pollinator sharing. Our results highlight the importance of characterizing both traits and ecological niches in character displacement studies., (© 2022 The Authors. Evolution © 2022 The Society for the Study of Evolution.)

Fertilization in angiosperms involves the germination of pollen on the stigma, followed by the extrusion of a pollen tube that elongates through the style and delivers two sperm cells to the embryo sac. Sexual selection could occur throughout this process when male gametophytes compete for fertilization. The strength of sexual selection during pollen competition should be affected by the number of genotypes deposited on the stigma. As increased self-fertilization reduces the number of mating partners, and the genetic diversity and heterozygosity of populations, it should thereby reduce the intensity of sexual selection during pollen competition. Despite the prevalence of mating system shifts, few studies have directly compared the molecular signatures of sexual selection during pollen competition in populations with different mating systems. Here we analyzed whole-genome sequences from natural populations of Arabis alpina, a species showing mating system variation across its distribution, to test whether shifts from cross- to self-fertilization result in molecular signatures consistent with sexual selection on genes involved in pollen competition. We found evidence for efficient purifying selection on genes expressed in vegetative pollen, and overall weaker selection on sperm-expressed genes. This pattern was robust when controlling for gene expression level and specificity. In agreement with the expectation that sexual selection intensifies under cross-fertilization, we found that the efficacy of purifying selection on male gametophyte-expressed genes was significantly stronger in genetically more diverse and outbred populations. Our results show that intra-sexual competition shapes the evolution of pollen-expressed genes, and that its strength fades with increasing self-fertilization rates., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.)