Outcome Of Competition Research Articles

How does intergroup familiarity moderate children’s merit-based resource allocation in the context of group-based competition?

Previous research has found that children can allocate resources according to competition outcomes (e.g., merit-based allocation) in interpersonal competitive contexts, but less research has investigated how children address merit-based allocations in the context of group-based competition, especially when influenced by intergroup familiarity. To address these issues, children (N = 374) aged 5–6 years old and 7–8 years old were asked to participate in an intergroup game with a familiar or unfamiliar group in the form of a competition (further divided into win and lose conditions) or noncompetition. They were then assessed on their resource allocation, reasoning and judgments of others’ allocations. We found that children as young as 5 years old can overcome group bias and adhere to allocating meritoriously in group-based competitive contexts. Furthermore, intergroup familiarity could decrease the effect of group bias on children’s merit-based allocation, but this tendency weakens with age. Finally, children consistently judged equal allocations positively regardless of actual allocation. The results indicated that with age, children were better able to weigh the moral concerns of merit and the social concerns of intergroup familiarity when determining the allocation of resources in group-based competition.

Enhancing Skeletal Muscle Rehabilitation: The Effects of Diclofenac Phonophoresis and Shock Wave Therapy on Serum Creatine Kinase in Athletes With Delayed-Onset Muscle Soreness.

Background Delayed-onset muscle soreness (DOMS) is a common condition in athletes characterized by muscle pain and stiffness after intense or unfamiliar exercise. It significantly impairs an athlete's performance by reducing muscle strength, flexibility, and overall physical capacity, often leading to suboptimal training or competition outcomes. Managing and mitigating DOMS is crucial for athletes to maintain peak performance and prevent potential injuries. The evaluation of effective treatment techniques is essential for expediting DOMS recovery by identifying biomarkers of skeletal muscle damage. This approach not only aids in optimizing recovery strategies but also contributes to the rehabilitation process, enabling athletes to return to peak performance quickly and safely. This study aims to evaluate the effects of shock wave therapy and diclofenac phonophoresis on serum creatine kinase levels in novice athletes suffering from DOMS in comparison to a control group. This research aims to assess the potential benefits of these therapeutic interventions in reducing skeletal muscle damage and enhancing recovery for individuals new to athletic training. Methodology A total of 48 novice athletes were recruited using simple random sampling and the block randomization approach to participate in this single-blind, multi-group, repeated-measures design. Male novice athletes in the age group of 18-25 years were included, and athletes with elevated serum creatine kinase variables at baseline measurements were excluded from the study. Before obtaining a written informed consent form, athletes were made aware of the procedure and associated risks. Group A received focused shock wave therapy, Group B received diclofenac phonophoresis, while Group C received no treatment. The Epley formula was used to compute the one-repetition maximum for each subject. Blood samples were taken at the baseline, 24, 48, 72, and 96 hours. Blood samples were taken before initiation of the study, as well as 24 hours, 48 hours, 72 hours, and 96 hours after DOMS was induced. Creatine kinase skeletal muscle biomarker was used as a dependent variable. Results In the evaluation of serum creatine kinase levels using analysis of variance (ANOVA), no statistically significant differences were observed between the three groups at baseline and 24-hour measurements (p > 0.05). However, statistically significant differences were found between the three groups at 48 hours, 72 hours, and 96 hours (p < 0.05). The repeated-measures ANOVA revealed significant overall changes in creatine kinase levels within the three groups, indicating time-dependent effects (p < 0.05). Specifically, during the 48 to 96-hour interval, the shock wave therapy group showed a lower mean value compared to the diclofenac phonophoresis group, followed by the control group. Conclusions The study demonstrates that a single administration of focused shock wave therapy effectively mitigated the elevation of creatine kinase levels in novice athletes with DOMS, surpassing the outcomes of diclofenac phonophoresis and the control group. These findings suggest the potential benefits of shock wave therapy in accelerating recovery from DOMS in the athletic population.

Do Mental Training Level and Perceived Fatigue Affect Competition Outcome in Volleyball?

The aim of this study was to investigate the effects of mental training (MT) and perceived fatigue levels (PF) on the performance of volleyball players participating in the Junior Volleyball Regional Championships. A total of 225 athletes from 10 girls' and 11 boys' volleyball teams were selected as participants. Prior to the competitions, the athletes completed two surveys, namely the "Chalder Fatigue Scale" and the " Mental Training Qestionnaire-SMTQ," to assess their PF levels and MT proficiency, respectively. Following the conclusion of the championship, the competition scores of all teams were obtained from the School Sports Federation. To examine the relationships among PF, MT levels, and competition scores, a Pearson correlation analysis was conducted. The results revealed a significant negative correlation between MT level and PF level (r = -.305, p

A predominant role of genotypic variation in both expression of sperm competition genes and paternity success in Drosophila melanogaster.

Sperm competition is a crucial aspect of male reproductive success in many species, including Drosophila melanogaster, and seminal fluid proteins (Sfps) can influence sperm competitiveness. However, the combined effect of environmental and genotypic variation on sperm competition gene expression remains poorly understood. Here, we used Drosophila Genetic Reference Panel (DGRP) inbred lines and manipulated developmental population density (i.e. larval density) to test the effects of genotype, environment and genotype-by-environment interactions (GEI) on the expression of the known sperm competition genes Sex Peptide, Acp36DE and CG9997. High larval density resulted in reduced adult body size, but expression of sperm competition genes remained unaffected. Furthermore, we found no significant GEI but genotypic effects in the expression of SP and Acp36DE. Our results also revealed GEI for relative competitive paternity success (second male paternity; P2), with genes' expression positively correlated with P2. Given the effect of genotype on the expression of genes, we conducted a genome-wide association study (GWAS) and identified polymorphisms in putative cis-regulatory elements as predominant factors regulating the expression of SP and Acp36DE. The association of genotypic variation with sperm competition outcomes, and the resilience of sperm competition genes' expression against environmental challenges, demonstrates the importance of genome variation background in reproductive fitness.

Genome streamlining and clonal erosion in nutrient-limited environments: a test using genome-size variable populations.

Some selection-based theories propose that genome streamlining, favoring smaller genome sizes, is advantageous in nutritionally limited environments, particularly under P-limitation. To test this prediction, we conducted several experimental evolution trials on clonal populations of a facultatively asexual rotifer that exhibits intraspecific variation in genome size. Most trials showed a rapid decline in clonal diversity, which was accelerated in populations that were initially non-adapted. Populations consisting of three rotifer clones often became monoclonal within a few weeks, while populations starting with 120 clones eroded to ten multi-locus genotypes, of which only five were abundant in higher numbers. While P-limitation affected population growth during the experiments, it did not affect the outcome of clonal competition or the speed at which clonal diversity was lost. Common garden transplant experiments revealed that the evolved populations were better adapted to the experimental conditions than the ancestral controls. However, contrary to expectations, the evolved populations did not show an overrepresentation of small genomes. Intermediate genomes were also frequently abundant, although very large genomes were rare. Our findings suggest that fitness is more influenced by genotypic differences among clones than by differences in GS, and indicate that such differences might hinder genome streamlining during early adaptation to a new environment.

Review on Wearable Technology in Sports: Concepts, Challenges and Opportunities

Wearable technology is increasingly vital for improving sports performance through real-time data analysis and tracking. Both professional and amateur athletes rely on wearable sensors to enhance training efficiency and competition outcomes. However, further research is needed to fully understand and optimize their potential in sports. This comprehensive review explores the measurement and monitoring of athletic performance, injury prevention, rehabilitation, and overall performance optimization using body wearable sensors. By analyzing wearables’ structure, research articles across various sports, and commercial sensors, the review provides a thorough analysis of wearable sensors in sports. Its findings benefit athletes, coaches, healthcare professionals, conditioners, managers, and researchers, offering a detailed summary of wearable technology in sports. The review is expected to contribute to future advancements in wearable sensors and biometric data analysis, ultimately improving sports performance. Limitations such as privacy concerns, accuracy issues, and costs are acknowledged, stressing the need for legal regulations, ethical principles, and technical measures for safe and fair use. The importance of personalized devices and further research on athlete comfort and performance impact is emphasized. The emergence of wearable imaging devices holds promise for sports rehabilitation and performance monitoring, enabling enhanced athlete health, recovery, and performance in the sports industry.

Strong ethanol- and frequency-dependent ecological interactions in a community of wine-fermenting yeasts

Natural wine fermentation depends on a complex consortium of native microorganisms rather than inoculation of industrial yeast strains. While this diversity of yeasts can result in an increased repertoire of wine flavors and aromas, it can also result in the inhibition of Saccharomyces cerevisiae, which is uniquely able to complete fermentation. Understanding how yeast species interact with each other within the wine-fermenting community and disentangling ecological interactions from environmental impacts on growth rates, is key to developing synthetic communities that can provide the sensory benefits of natural fermentation while lowering the risk of stuck ferments. Here, we co-culture all pairwise combinations of five commonly isolated wine-fermenting yeasts and show that competitive outcomes are a strong function of ethanol concentration, with frequency-dependent bistable interactions common at low alcohol and an increasingly transitive competitive hierarchy developing as alcohol increases. We also show that pairwise outcomes are predictive of five-species community outcomes, and that frequency dependence in pairwise interactions propagates to alternative states in the full community, highlighting the importance of species abundance as well as composition. We also observe that monoculture growth rates are only weakly predictive of competitive success, highlighting the need to incorporate ecological interactions when designing synthetic fermenting communities.

The competition between heterotrophic denitrification and DNRA pathways in hyporheic zone and its impact on the fate of nitrate

Dissimilatory nitrate reduction to ammonium (DNRA) and heterotrophic denitrification (DEN) are recognized as two key nitrate reduction pathways competing for both nitrate and dissolved organic carbon (DOC). However, the mechanisms and influencing factors governing this competition in the dynamic hyporheic system remain unclear. In this study, a numerical model that coupled flow, reactive solute transport and microbial activities was developed to investigate the competition between DEN and DNRA in the hyporheic zone. The modeling results indicate that DNRA hotspots are distributed along the hyporheic flow path. The greater the flow velocity, the farther the DNRA hotspots are from the water-sediment interface. In the simulation scenario involving river stage fluctuations, the relative contribution of DNRA resulting from these fluctuations under a small initial hydraulic gradient (0.001) of the hyporheic zone increased by 60% compared to the range observed under a large initial hydraulic gradient (0.01). The C/N ratio in river water does not dictate the prevailing microbial group at specific locations within the hyporheic zone. Instead, the river C/N ratio governs the competition outcomes across the entire hyporheic system, demonstrating a three-phase pattern. The nitrate removal efficiency in the hyporheic system approaches 100% at C/N = 3. As the stream C/N ratio increases, the contribution of DNRA gradually rises and can reach 80% (C/N = 10). At this point, the contribution of the heterotrophic denitrifying bacteria and their corresponding nitrate removal efficiency decreases to only about 20%. Disregarding the DNRA reaction might lead to an underestimation of nitrate removal efficiency of a hyporheic zone. Our investigation improves the understanding of nitrate fate in hyporheic zones and provides a scientific foundation for watershed management and pollution control.

Fungal Fight Club: phylogeny and growth rate predict competitive outcomes among ectomycorrhizal fungi.

Ectomycorrhizal fungi are among the most prevalent fungal partners of plants and can constitute up to one-third of forest microbial biomass. As mutualistic partners that supply nutrients, water, and pathogen defense, these fungi impact host plant health and biogeochemical cycling. Ectomycorrhizal fungi are also extremely diverse, and the community of fungal partners on a single plant host can consist of dozens of individuals. However, the factors that govern competition and coexistence within these communities are still poorly understood. In this study, we used in vitro competitive assays between five ectomycorrhizal fungal strains to examine how competition and pH affect fungal growth. We also tested the ability of evolutionary history to predict the outcomes of fungal competition. We found that the effects of pH and competition on fungal performance varied extensively, with changes in growth media pH sometimes reversing competitive outcomes. Furthermore, when comparing the use of phylogenetic distance and growth rate in predicting competitive outcomes, we found that both methods worked equally well. Our study further highlights the complexity of ectomycorrhizal fungal competition and the importance of considering phylogenetic distance, ecologically relevant traits, and environmental conditions in predicting the outcomes of these interactions.

Connecting local and regional scales with stochastic metacommunity models: Competition, ecological drift, and dispersal

AbstractDespite the well known scale‐dependency of ecological interactions, relatively little attention has been paid to understanding the dynamic interplay between various spatial scales. This is especially notable in metacommunity theory, where births and deaths dominate dynamics within patches (the local scale), and dispersal and environmental stochasticity dominate dynamics between patches (the regional scale). By considering the interplay of local and regional scales in metacommunities, the fundamental processes of community ecology—selection, drift, and dispersal—can be unified into a single theoretical framework. Here, we analyze three related spatial models that build on the classic two‐species Lotka–Volterra competition model. Two open‐system models focus on a single patch coupled to a larger fixed landscape by dispersal. The first is deterministic, while the second adds demographic stochasticity to allow ecological drift. Finally, the third model is a true metacommunity model with dispersal between a large number of local patches, which allows feedback between local and regional scales and captures the well studied metacommunity paradigms as special cases. Unlike previous simulation models, our metacommunity model allows the numerical calculation of equilibria and invasion criteria to precisely determine the outcome of competition at the regional scale. We show that both dispersal and stochasticity can lead to regional outcomes that are different than predicted by the classic Lotka–Volterra competition model. Regional exclusion can occur when the nonspatial model predicts coexistence or founder control, due to ecological drift or asymmetric stochastic switching between basins of attraction, respectively. Regional coexistence can result from local coexistence mechanisms or through competition‐colonization or successional‐niche trade‐offs. Larger dispersal rates are typically competitively advantageous, except in the case of local founder control, which can favor intermediate dispersal rates. Broadly, our models demonstrate the importance of feedback between local and regional scales in competitive metacommunities and provide a unifying framework for understanding how selection, drift, and dispersal jointly shape ecological communities.

Continuous Glucose Monitoring in Endurance Athletes: Interpretation and Relevance of Measurements for Improving Performance and Health

Blood glucose regulation has been studied for well over a century as it is intimately related to metabolic health. Research in glucose transport and uptake has also been substantial within the field of exercise physiology as glucose delivery to the working muscles affects exercise capacity and athletic achievements. However, although exceptions exist, less focus has been on blood glucose as a parameter to optimize training and competition outcomes in athletes with normal glucose control. During the last years, measuring glucose has gained popularity within the sports community and successful endurance athletes have been seen with skin-mounted sensors for continuous glucose monitoring (CGM). The technique offers real-time recording of glucose concentrations in the interstitium, which is assumed to be equivalent to concentrations in the blood. Although continuous measurements of a parameter that is intimately connected to metabolism and health can seem appealing, there is no current consensus on how to interpret measurements within this context. Well-defined approaches to use glucose monitoring to improve endurance athletes’ performance and health are lacking. In several studies, blood glucose regulation in endurance athletes has been shown to differ from that in healthy controls. Furthermore, endurance athletes regularly perform demanding training sessions and can be exposed to high or low energy and/or carbohydrate availability, which can affect blood glucose levels and regulation. In this current opinion, we aim to discuss blood glucose regulation in endurance athletes and highlight the existing research on glucose monitoring for performance and health in this population.

Unsupervised cycle-consistent adversarial attacks for visual object tracking

Adversarial attacks on visual object tracking have been gaining momentum in the quest to assess and enhance the robustness and security of object tracking models. Most adversarial attack strategies for object tracking rely on fully supervised attacks; that is, they necessitate the use of labels. However, it is not feasible to apply these labeled video object tracking techniques to all attacks. As such, this paper presents an unsupervised attack methodology against visual object tracking models. The approach employs the cycle consistency principle of object tracking models to maximize the inconsistency between forward and backward tracking, thereby providing effective countermeasures. Additionally, this paper introduces a contextual attack method, leveraging the information from the attack object’s region and its surrounding contextual regions. This strategy attacks the object region and its surrounding context regions simultaneously, aiming to decrease its response score to the attack. The proposed attack method is assessed across various types of deep learning-based object trackers. Experimental results on multiple benchmarks reveal that the suggested method yields competitive attack outcomes.

Female reproductive fluid and male seminal fluid: a non-gametic conflict for post-mating control.

Growing evidence shows that non-gametic components released by both males and females can significantly drive sperm competition outcomes. Seminal fluid (SF) was shown to influence paternity success by affecting rival males' sperm performance, and, in some species with male alternative reproductive tactics, to selectively decrease the fertilization success of males of the opposite tactic. Female reproductive fluid (FRF) has been proven to differentially influence ejaculates of different males and bias fertilization towards specific partners. Whether, and with what outcome, these two processes can intersect to influence sperm competition is still unknown. Here we explore this scenario in the grass goby (Zosterisessor ophiocephalus), a fish with territorial-sneaker reproductive tactics, where sneaker males can exploit the territorials' SF while penalizing territorial sperm performance with their own fluid. To test whether FRF can rebalance the ejaculate competition in favour of territorial males, we used in vitro fertilization with a SF mixture (territorial + sneaker), using increasing concentrations of FRF, to simulate the natural conditions that ejaculates encounter towards the eggs. Our findings revealed a differential effect of FRF on the different tactics' fertilization success, favouring territorial ejaculates, possibly through an attenuation of the detrimental effects of sneaker SF, and enabling females to regain control over the fertilization process.

Price-Directed Search, Product Differentiation and Competition

Especially in many online markets, consumers can readily observe prices, but may need to inspect products further to assess their suitability. We study the effects of product differentiation and search costs on competition and market outcomes in a tractable model of price-directed consumer search. We find that: (i) firms’ equilibrium pricing always induces efficient search behavior; (ii) for relatively large product differentiation, welfare distortions still occur because some consumers (may) forgo consumption; and (iii) lower search costs lead to stochastically higher prices, which increases firms’ expected profits and decreases their frequency of sales. Consumer surplus often falls when search costs decrease.

Analyzing predictive approaches in martial arts research

Background and Study Aim. Predicting the results of martial arts competitions is an important task that attracts the attention of both sports analysts and fans of these sports. The objective of this study is to perform an analytical examination of publications on martial arts prediction, with the aim of identifying the primary research directions in this field. Materials and Methods. the bibliometric analysis of PubMed database data was used to create a sample of studies at 18.05.2023. The keywords "prediction", "martial arts" were used for the search. A total of 151 publications were found. The first publication was dated 1983. VOSviewer 1.6.19 program was used: keyword analysis method and direct citation analysis with the construction of bibliometric maps, the visualization of cluster density, weights – citations. Results. 51 journals from 21 countries were identified. The unconditional leader among the countries is the United States (16 journals). Between 1983 and May 18, 2023, 741 scientific works were found. The analysis involved 67 authors whose link strength was more than 0. Eight clusters were identified. They were characterized by the presence of 271 links with total link strength of 276. The number of items in the clusters did not have a significant difference; this can be explained by the popularity of all directions in the research. The authors of the seventh and eighth clusters had the most publications. To visualize the network 63 items (keywords) were selected. They were grouped into 4 clusters. The network includes 951 links; the total link strength is 4027. The most popular studies are highlighted. These studies include the following keywords: "humans", "martial arts", "female", "male", "athletes", "young adult", "middle aged". Conclusions. The analysis of the bibliometric maps revealed the tendencies of scientific research and highlighted the priority areas. The relevance of the problem of prediction in martial arts is confirmed. An increase in the number of publications in PubMed database over the past decade has been observed. The main areas of research include martial arts, health, sports training, and humans. Most publications focus on utilizing artificial intelligence and machine learning techniques for predicting competition outcomes. Additionally, they explore the application of analytical tools to uncover patterns in data and identify critical factors that impact competition results. Modern technologies and the availability of big data open up new possibilities for predicting competitive success in martial arts.

Resource competition can explain simplicity in microbial community assembly

Predicting the composition and diversity of communities is a central goal in ecology. While community assembly is considered hard to predict, laboratory microcosms often follow a simple assembly rule based on the outcome of pairwise competitions. This assembly rule predicts that a species that is excluded by another species in pairwise competition cannot survive in a multispecies community with that species. Despite the empirical success of this bottom-up prediction, its mechanistic origin has remained elusive. In this study, we elucidate how this simple pattern in community assembly can emerge from resource competition. Our geometric analysis of a consumer-resource model shows that trio community assembly is always predictable from pairwise outcomes when one species grows faster than another species on every resource. We also identify all possible trio assembly outcomes under three resources and find that only two outcomes violate the assembly rule. Simulations demonstrate that pairwise competitions accurately predict trio assembly with up to 100 resources and the assembly of larger communities containing up to twelve species. We then further demonstrate accurate quantitative prediction of community composition using the harmonic mean of pairwise fractions. Finally, we show that cross-feeding between species does not decrease assembly rule prediction accuracy. Our findings highlight that simple community assembly can emerge even in ecosystems with complex underlying dynamics.

Beyond capacity: Contractual form in electricity reliability obligations

Liberalized electricity markets often include resource adequacy mechanisms that require consumers to contract with generation resources well in advance of real-time operations. While administratively defined mechanisms have most commonly taken the form of a capacity obligation, efficient markets would feature a broad array of arrangements adapted to the risk profiles and appetites of market participants. This article considers how the financial hedge embedded in alternative resource adequacy contract designs can induce different responses from risk-averse investors, with consequences for the resource mix and market structure. We construct a stochastic equilibrium model describing a competitive market with incomplete risk trading and compute investment equilibria under different contracting regimes. Two policy recommendations result. First, to avoid creating inefficiency by crowding out other forms of risk sharing, system operators should allow resources contracted through other means to opt out of mandatory capacity mechanisms, with their contribution to those requirements subtracted from administratively defined demand curves. Second, if they wish to promote a single contractual form, regulators should consider replacing existing option-like capacity mechanisms with a shaped forward contract for energy. Beyond these recommendations, we discuss the tension that liberalized systems face in seeking to promote both reliability and competitive outcomes.

Crop Host Influences on Outcomes of Competition Between Aspergillus Section Flavi Species Coinfecting Maize and Groundnuts

Aspergillus section Flavi species co-occur and contaminate crops, including maize and groundnuts, with aflatoxins. Competition among A. flavus genotypes is influenced by crop host, but competition between Aspergillus species has not been examined. The objectives of the current study were to (i) assess competition among four aflatoxin-producing species on maize and groundnuts and (ii) evaluate within-species variation in competitive ability during coinfection with another species on the two crops. For the first objective, maize and groundnut kernels were coinoculated with all possible pairs of A. flavus, A. parasiticus, A. aflatoxiformans, and an unnamed taxon known as the Lethal Aflatoxicosis Fungus (LAF). For the second objective, three isolates from each of the four species were coinoculated with a representative isolate of a competing species on the two hosts. In all experiments, isolates were cocultured for 7 days at 30°C, and then aflatoxins and total conidia were measured, and the percentages of each species within a treatment were assessed with quantitative pyrosequencing. Maize kernels supported greater aflatoxin production than groundnuts, whereas groundnuts supported greater sporulation than maize. Hosts differentially influenced competition between species, with A. flavus generally more competitive on maize and LAF more competitive on groundnuts. Overall, A. flavus and LAF were the most competitive species, whereas A. parasiticus was the least competitive. However, isolates within a species varied in competitive ability and in their response to host and competing species. Results suggest that although crop hosts influence Aspergillus community composition, within-species variability makes it difficult to predict outcomes of competition on a particular crop. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

Trade-offs between immunity and competitive ability in fighting ant males

BackgroundFighting disease while fighting rivals exposes males to constraints and trade-offs during male-male competition. We here tested how both the stage and intensity of infection with the fungal pathogen Metarhizium robertsii interfere with fighting success in Cardiocondyla obscurior ant males. Males of this species have evolved long lifespans during which they can gain many matings with the young queens of the colony, if successful in male-male competition. Since male fights occur inside the colony, the outcome of male-male competition can further be biased by interference of the colony’s worker force.ResultsWe found that severe, but not yet mild, infection strongly impaired male fighting success. In late-stage infection, this could be attributed to worker aggression directed towards the infected rather than the healthy male and an already very high male morbidity even in the absence of fighting. Shortly after pathogen exposure, however, male mortality was particularly increased during combat. Since these males mounted a strong immune response, their reduced fighting success suggests a trade-off between immune investment and competitive ability already early in the infection. Even if the males themselves showed no difference in the number of attacks they raised against their healthy rivals across infection stages and levels, severely infected males were thus losing in male-male competition from an early stage of infection on.ConclusionsMales of the ant C. obscurior have a well-developed immune system that raises a strong immune response very fast after fungal exposure. This allows them to cope with mild pathogen exposures without compromising their success in male-male competition, and hence to gain multiple mating opportunities with the emerging virgin queens of the colony. Under severe infection, however, they are weak fighters and rarely survive a combat already at early infection when raising an immune response, as well as at progressed infection, when they are morbid and preferentially targeted by worker aggression. Workers thereby remove males that pose a future disease threat by biasing male-male competition. Our study thus reveals a novel social immunity mechanism how social insect workers protect the colony against disease risk.

Who’s afraid of the GOATs? - Shadow effects of tennis superstars

In multi-stage tournaments, anticipated competition in future stages might affect the outcome of competition in the current stage. In particular, the presence of superstars might demotivate the next-best competitors from seeking to advance to later rounds, where they ultimately are likely to face a superstar. Data from men’s professional tennis tournaments held between 2004 and 2019 affirm that the participation of superstars (Djokovic, Nadal, Federer, and Murray) reduces the probability that the remaining Top 20 players win their matches. Such shadow effects arise even in very early tournament stages, in which favoured players lose more often than expected, given their ability. The effects are more pronounced when multiple superstars compete in the tournament and disappear once all superstars have been eliminated from competition. Furthermore, shadow effects increase the probability of retirement of strong but non-superstar competitors and disappear once superstar performance is not dominant.