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2.
Artigo em Inglês | MEDLINE | ID: mdl-36078546

RESUMO

The mass start speed skating (MSSS) is a new event for the 2018 PyeongChang Winter Olympic Games. Considering that the event rankings were based on points gained on laps, it is worthwhile to investigate the pacing behaviors on each lap that directly influence the skater's ranking at the end of the race. To the best of our knowledge, this is the first study investigating the pacing behavior on the MSSS. The aim of this study was to analyze the pacing behaviors and performance on MSSS regarding skaters' level (SL), competition stage (semi-final/final) (CS), and gender (G). All the male and female races in the World Cup and World Championships were analyzed during the 2018-2019 and 2019-2020 seasons. As a result, a total of 601 skaters (male = 350 and female = 251) from 36 games (male = 21 and female = 15) were observed. The one-way ANOVA for repeated measures was used to compare skaters' pacing behavior on each lap, and the three-way ANOVA for repeated measures was used to identify the influence of SL, CS, and G on skaters' pacing behaviors and total time spent. In general, the results showed that the pacing behaviors from fast to slow were group one (laps 4, 8, 12, 15, 16), group two (laps 5, 9, 13, 14), group three (laps 3, 6, 7, 10, 11), and group four (laps 1 and 2) (p ≤ 0.001 for all groups). For CS, the total time spent in the final was less than the semi-final (p ≤ 0.001). For SL, top-level skaters spent less total time than the middle-level and low-level skaters (p ≤ 0.002), while there was no significant difference between the middle and low levels (p = 0.214). For G, the male skaters spent less total time than females on all laps (p ≤ 0.048). Current findings could help coaching staff to better understand the pacing behaviors regarding SL, CS, and G. In particular, the identified performance trends may allow controlling for pacing strategy and decision making before and during the race.


Assuntos
Desempenho Atlético , Patinação , Futebol , Comportamento Competitivo , Feminino , Humanos , Masculino , Fatores de Tempo
3.
Proc Natl Acad Sci U S A ; 119(35): e2204400119, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35994662

RESUMO

Ecological niche differences are necessary for stable species coexistence but are often difficult to discern. Models of dietary niche differentiation in large mammalian herbivores invoke the quality, quantity, and spatiotemporal distribution of plant tissues and growth forms but are agnostic toward food plant species identity. Empirical support for these models is variable, suggesting that additional mechanisms of resource partitioning may be important in sustaining large-herbivore diversity in African savannas. We used DNA metabarcoding to conduct a taxonomically explicit analysis of large-herbivore diets across southeastern Africa, analyzing ∼4,000 fecal samples of 30 species from 10 sites in seven countries over 6 y. We detected 893 food plant taxa from 124 families, but just two families-grasses and legumes-accounted for the majority of herbivore diets. Nonetheless, herbivore species almost invariably partitioned food plant taxa; diet composition differed significantly in 97% of pairwise comparisons between sympatric species, and dissimilarity was pronounced even between the strictest grazers (grass eaters), strictest browsers (nongrass eaters), and closest relatives at each site. Niche differentiation was weakest in an ecosystem recovering from catastrophic defaunation, indicating that food plant partitioning is driven by species interactions, and was stronger at low rainfall, as expected if interspecific competition is a predominant driver. Diets differed more between browsers than grazers, which predictably shaped community organization: Grazer-dominated trophic networks had higher nestedness and lower modularity. That dietary differentiation is structured along taxonomic lines complements prior work on how herbivores partition plant parts and patches and suggests that common mechanisms govern herbivore coexistence and community assembly in savannas.


Assuntos
Dieta , Pradaria , Herbivoria , Mamíferos , Plantas , África , Animais , Comportamento Competitivo , Código de Barras de DNA Taxonômico , Dieta/estatística & dados numéricos , Dieta/veterinária , Fabaceae/classificação , Fabaceae/genética , Fezes , Mamíferos/classificação , Mamíferos/fisiologia , Plantas/classificação , Plantas/genética , Poaceae/classificação , Poaceae/genética , Chuva
4.
Front Neuroendocrinol ; 66: 101015, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35835214

RESUMO

Emerging evidence suggests that hormonal contraceptives (HCs) impact psychological outcomes through alterations in neurophysiology. In this review, we first introduce a theoretical framework for HCs as disruptors of steroid hormone modulation of socially competitive attitudes and behaviors. Then, we comprehensively examine prior research comparing HC users and non-users in outcomes related to competition for reproductive, social, and financial resources. Synthesis of 46 studies (n = 16,290) led to several key conclusions: HC users do not show the same menstrual cycle-related fluctuations in self-perceived attractiveness and some intrasexual competition seen in naturally-cycling women and, further, may show relatively reduced status- or achievement-oriented competitive motivation. However, there a lack of consistent or compelling evidence that HC users and non-users differ in competitive behavior or attitudes for mates or financial resources. These conclusions are tentative given the notable methodological limitations of the studies reviewed. Implications and recommendations for future research are discussed.


Assuntos
Comportamento Competitivo , Anticoncepcionais Orais Hormonais , Comportamento Competitivo/fisiologia , Feminino , Hormônios , Humanos , Ciclo Menstrual/fisiologia , Motivação , Progesterona
6.
Artigo em Inglês | MEDLINE | ID: mdl-35805450

RESUMO

BACKGROUND: Anxiety is one of the most complex and the most studied constructs in psychology, and it is extremely frequent in high-level sportsmen and women. The main goal was to study the influence of sex, age, type of sport, sport modality, other professional occupation, and competitive level on the competitive anxiety symptoms and self-confidence of elite athletes. METHODS: A descriptive cross-sectional study was carried out with Colombian elite athletes who were members of the "Support to the Excellence Coldeportes Athlete" program. The total population studied included 334 Colombian elite athletes: mean age 27.10 ± 6.57 years old with 13.66 ± 6.37 years practicing his/her sports modality. The precompetitive anxiety symptoms of the participants were assessed using the Competitive State Anxiety Inventory-2R (CSAI-2R). RESULTS: Men showed higher levels of self-confidence than women. Younger athletes had a higher cognitive and somatic anxiety. The athletes of individual sports had a higher mean somatic anxiety than those of collective sports. The higher-level athletes had lower values of cognitive and somatic anxiety and higher levels of self-confidence. Finally, the values of anxiety symptoms positively correlated with each other, and negatively correlated with self-confidence. CONCLUSION: Individualised psychological intervention programs adapted to elite athletes are needed, considering the divergent results found in various variables of scientific interest.


Assuntos
Atletas , Comportamento Competitivo , Adulto , Ansiedade/psicologia , Atletas/psicologia , Colômbia , Estudos Transversais , Feminino , Humanos , Masculino , Adulto Jovem
7.
Sci Rep ; 12(1): 10740, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35750752

RESUMO

Humans compete for jobs, promotions, income, status, and many other scarce goods. In some situations, allocating scarce goods via competition is socially beneficial. In other situations, competition is not necessary to allocate goods, and nevertheless engaging in competition creates inefficiencies and welfare loss. We use an incentivized lab experiment to study whether people compete differently depending on whether allocating scarce goods via competition is socially wasteful or socially beneficial. We find that competition behavior is strikingly similar in situations where competing is socially wasteful and socially beneficial. Accordingly, there is large excess competition in situations of wasteful competition, creating considerable efficiency losses. We find evidence of a social trap involved in this excess competition. People are considerably more likely to compete if they believe others compete, and their beliefs on others' competition are similar in situations where competing is socially wasteful and socially beneficial. Interventions aimed at lowering beliefs on others' competition may be an effective method of lowering excess competition to prevent inefficiencies and welfare loss.


Assuntos
Comportamento Competitivo , Humanos
8.
J Sports Sci ; 40(12): 1392-1398, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35675384

RESUMO

The sequence of moves in a dynamic team tournament may distort the ex-ante winning probabilities and harm efficiency. This paper compares seven soccer penalty shootout rules that determine the kicking order, from a theoretical perspective. Their fairness is evaluated in a reasonable model of First Mover Advantage. We also discuss the probability of reaching the sudden death stage. In the case of stationary scoring probabilities, dynamic mechanisms are not better than static rules. However, it is worth compensating the second-mover by making it the first-mover in the sudden death stage. Our work has the potential to impact decision-makers who can guarantee fairer outcomes in dynamic tournaments by a carefully chosen sequence of actions.


Assuntos
Desempenho Atlético , Futebol , Comportamento Competitivo , Morte Súbita , Humanos , Probabilidade
9.
Proc Natl Acad Sci U S A ; 119(25): e2119176119, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35700363

RESUMO

Conflicts between social groups or "intergroup contests" are proposed to play a major role in the evolution of cooperation and social organization in humans and some nonhuman animal societies. In humans, success in warfare and other collective conflicts depends on both fighting group size and the presence and actions of key individuals, such as leaders or talismanic warriors. Understanding the determinants of intergroup contest success in other warlike animals may help to reveal the role of these contests in social evolution. Using 19 y of data on intergroup encounters in a particularly violent social mammal, the banded mongoose (Mungos mungo), we show that two factors, the number of adult males and the age of the oldest male (the "senior" male), have the strongest impacts on the probability of group victory. The advantage conferred by senior males appears to stem from their fighting experience. However, the galvanizing effect of senior males declines as they grow old until, at very advanced ages, senior males become a liability rather than an asset and can be evicted. As in human conflict, strength in numbers and the experience of key individuals combine to determine intergroup contest success in this animal society. We discuss how selection arising from intergroup contests may explain a suite of features of individual life history and social organization, including male eviction, sex-assortative alloparental care, and adult sex ratio.


Assuntos
Comportamento Animal , Comportamento Competitivo , Herpestidae , Fatores Etários , Animais , Herpestidae/psicologia , Hostilidade , Masculino , Probabilidade
10.
J Sports Sci Med ; 21(2): 233-244, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35719225

RESUMO

The aims of the study were to provide benchmarks and normative data for 100 m, 200 m, and 400 m short-course individual medley (IM) races, investigate differences between the various swimming strokes and turns involved in IM, and quantify the effect and contribution of various race sections on swimming performance. All IM races (n = 320) at the 2019 European Short-Course Swimming Championships were video monitored and digitized with interrater reliability described by a mean intra-class correlation coefficient of 0.968. Normative data were provided for the eight finalists of each event (FINA points = 886 ± 37) and the eight slowest swimmers from each event (FINA points = 688 ± 53). Contribution and effects of race sections on swimming performance were investigated using stepwise regression analysis based on all races of each event. Regression analysis explained 97-100% of total variance in race time and revealed turn time (ß ≥ 0.53) as distinguishing factor in short-course IM races in addition to swim velocity (ß ≥ -0.28). Start time only affected 100 m (ß ≥ 0.14) and 200 m (ß ≥ 0.04) events. Fastest turn times were found for the butterfly/backstroke turn. Breaststroke showed slowest swim velocities and no difference between fastest and slowest 100 m IM swimmers. Therefore, breaststroke may provide largest potential for future development in IM race times. Correlation analyses revealed that distance per stroke (r ≥ -0.39, P < 0.05) rather than stroke rate (r ≤ -0.18, P > 0.05) is a performance indicator and may be used by coaches and performance analysts to evaluate stroke mechanics in male IM swimmers despite its more complex assessment. Performance analysts, coaches, and swimmers may use the present normative data to establish minimal and maximal requirements for European Championship participation and to create specific drills in practice.


Assuntos
Desempenho Atlético , Natação , Comportamento Competitivo , Humanos , Masculino , Análise de Regressão , Reprodutibilidade dos Testes
11.
Rev. psicol. deport ; 31(2): 9-20, Mayo 14, 2022. tab, graf
Artigo em Inglês | IBECS | ID: ibc-208107

RESUMO

The purpose of this study is to determine the role of sports performance inventories in athlete performance by incorporating the athlete’s emotional control, team orientation, positive attitude, competitiveness, and mental toughness. Indeed, athletes face exterior challenges and internal ones that impair their performance. This study is cross-sectional and utilizes a questionnaire to collect quantitative data. The sample size for this study was 780, based on a response rate of 45% among the respondent population of Jordanian athletes. This study finds that the psychological measures of athlete emotional control, team orientation, and positive attitude have a critical role in improving athletes’ competitiveness and performance. This study is notable because it explored the psychological measures used to collect data from respondents to comprehend the relationship established in the theoretical framework for examining their involvement in athlete performance. Additionally, this work has substantial theoretical and practical implications for athletes seeking to better their performance.(AU)


Assuntos
Humanos , Desempenho Atlético , Atletas , Autoavaliação (Psicologia) , Estresse Psicológico , Comportamento Competitivo , Sintomas Afetivos , Esgotamento Psicológico , Esportes , Estudos Transversais , Psicologia do Esporte , Inquéritos e Questionários , Jordânia
12.
Artigo em Inglês | MEDLINE | ID: mdl-35564428

RESUMO

Turn performances are important success factors for short-course races, and more consistent turn times may distinguish between higher and lower-ranked swimmers. Therefore, this study aimed to determine coefficients of variation (CV) and performance progressions (∆%) of turn performances. The eight finalists and eight fastest swimmers from the heats that did not qualify for the semi-finals, i.e., from 17th to 24th place, of the 100, 200, 400, and 800 (females only)/1500 m (males only) freestyle events at the 2019 European Short Course Championships were included, resulting in a total of 64 male (finalists: age: 22.3 ± 2.6, FINA points: 914 ± 31 vs. heats: age: 21.5 ± 3.1, FINA points: 838 ± 74.9) and 64 female swimmers (finalists: age: 22.9 ± 4.8, FINA points: 904 ± 24.5 vs. heats: age: 20.1 ± 3.6, FINA points: 800 ± 48). A linear mixed model was used to compare inter- and intra-individual performance variation. Interactions between CVs, ∆%, and mean values were analyzed using a two-way analysis of variance (ANOVA). The results showed impaired turn performances as the races progressed. Finalists showed faster turn section times than the eight fastest non-qualified swimmers from the heats (p < 0.001). Additionally, turn section times were faster for short-, i.e., 100 and 200 m, than middle- and long-distance races, i.e., 400 to 1500 m races (p < 0.001). Regarding variation in turn performance, finalists showed lower CVs and ∆% for all turn section times (0.74% and 1.49%) compared to non-qualified swimmers (0.91% and 1.90%, respectively). Similarly, long-distance events, i.e., 800/1500 m, showed lower mean CVs and higher mean ∆% (0.69% and 1.93%) than short-distance, i.e., 100 m events (0.93% and 1.39%, respectively). Regarding turn sections, the largest CV and ∆% were found 5 m before wall contact (0.70% and 1.45%) with lower CV and more consistent turn section times 5 m after wall contact (0.42% and 0.54%). Non-qualified swimmers should aim to match the superior turn performances and faster times of finalists in all turn sections. Both finalists and non-qualified swimmers should pay particular attention to maintaining high velocities when approaching the wall as the race progresses.


Assuntos
Desempenho Atlético , Comportamento Competitivo , Adolescente , Adulto , Análise de Variância , Feminino , Temperatura Alta , Humanos , Masculino , Natação , Adulto Jovem
13.
PLoS One ; 17(5): e0268171, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35511919

RESUMO

The goal of performance analysis is to capture the multitude of factors that affect sports strategy, and present them in an informative, interpretable, and accessible format. The aim of this study was to outline a performance analysis process in field hockey that captures, analyses and visualises strategy in layers of detail culminating in the creation of an RStudio Shiny application. Computerised notational analysis systems were developed to capture in-game events and ball tracking data of 74 matches from the Women's Pro League 2019. Game styles were developed using k-means cluster analysis to reduce detailed in-game events into practical profiles to identify the attack types, game actions and tempo of a team's strategy. Ball movement profiles were developed to identify the predictability (entropy) and direction (progression rates) of ball movements, and consequent distribution of possession in different attacking zones. The Shiny application, an interactive web-platform, links the information from simple game profiles with detailed game variables to understand each teams' holistic game plan, how they are different, and how to exploit these differences. The process outlined can be applied to any team invasion sport to understand, develop and communicate successful strategies under different match situations.


Assuntos
Desempenho Atlético , Hóquei , Logro , Comportamento Competitivo , Feminino , Humanos , Movimento
14.
Int J Sports Physiol Perform ; 17(7): 1119-1125, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35580843

RESUMO

PURPOSE: The Doha 2019 women's World Championship marathon took place in extreme hot (32 °C), humid conditions (74% relative humidity) culminating in unprecedented (41%) failure rates. We explored whether extreme heat or suboptimal pacing was responsible for diminished performance against a temperate "control" (London 2017: 19 °C, 59% relative humidity) and whether physical characteristics (eg, body surface area, estimated maximal oxygen uptake, habitual heat exposure) explained performance. METHOD: Five-kilometer-pace (km·h-1) data underwent repeated-measures analyses of hot (Doha, n = 40) versus temperate pacing and performance (London, n = 78) within and between marathon pacing (finisher quartiles normalized against personal best; n = 10 per group) and within hot marathon finishers versus nonfinishers (up to 10 km; normalized data). Possible predictors (multiple regression) of hot marathon pacing were explored. Tests to .05 alpha level, partial eta squared (ηp2) indicates effect size. RESULTS: Mean (SD) of Doha (14.82 [0.96] km·h-1) pace was slower (London: 15.74 [0.96] km·h-1; P = .00; ηp2=.500). In hot conditions, athletes finishing in positions 1 to 10 (group 1) started more conservatively (93.7% [2.1%] of personal best) than slower runners (groups 3 and 4; 96.6% [2.8%] of personal best; P < .05, ηp2=.303). Groups were not different at 15 km and then slowed immediately (groups 3 and 4) or after 20 km (group 2). Finishers and nonfinishers adopted similar pace up to 10 km (P > .05, ηp2 =.003). World ranking predicted (P = .00; r2 = .248) average pace in Doha. CONCLUSION: Extreme hot conditions reduced performance. Top 10 athletes adopted a conservative initial pace, whereas lower-placing athletes adopted a faster, aggressive start. Pacing alone does not explain high failure rates in nonfinishers. Athletes competing in the heat should initially pace conservatively to optimize performance.


Assuntos
Desempenho Atlético , Calor Extremo , Corrida , Comportamento Competitivo , Feminino , Humanos , Corrida de Maratona , Resistência Física
15.
Apunts, Med. esport (Internet) ; 57(214): 100385, April - June 2022. graf, tab
Artigo em Inglês | IBECS | ID: ibc-206324

RESUMO

Introduction: contextual variables associated with competitive stress may affect the perception of the well-being and recovery of futsal athletes.Material and Methods : twenty male professional futsal players responded to the Hooper Index (HI) and Total Quality of Recovery Scale (TQR) two hours before eleven official matches. Data were collected on age, predicted game difficulty, distance from the previous game, time interval since the previous game, ranking of the team and opponent, and outcome of the previous game of the team and the opponent (defeat/draw/win). Multivariate logistic regression analysis and the Spearman rank-sum test were used to identify stressors that influenced HI and TQR scores, considering p<0.05.Resultsthe HI was higher in the National League (11.2 ± 2.9 a.u., p<0.005) compared to the State championship (10.0 ± 2.4 a.u.). The DOMS were higher in National League (p<0.001) and games preceded by victory (p<0.005). The HI (r=-0.53, p<0.001), age (r=-0.18, p<0.01), and muscle pain (r = -0.39, p <0.001) correlated with the TQR. The TQR was higher in games preceded by defeat (15.5 ± 1.6) compared to victory (14.6 ± 1.7, p<0.01). The pre-game HI and TQR scores were not significantly different (p>0.05) in games that ended in victory, draw or defeat.Conclusionthe results suggest that the DOMS scores of HI and TQR reported before at home official Futsal games are correlated with contextual factors including the level of championship and outcome of the last game. (AU)


Assuntos
Humanos , Masculino , Estresse Psicológico/diagnóstico , Comportamento Competitivo , Futebol
16.
Artigo em Inglês | MEDLINE | ID: mdl-35457792

RESUMO

In sports, there has been a recent and active movement to promote mixed-gender competitions for achieving gender equality in the field. However, the current debate regarding its effects limitedly focuses on balancing the number of opportunities for females and neglects its effect on athlete performance. To address this gap, this study investigated whether and how mixed-gender competitions mitigate gender-specific disadvantages of interim leaders in dynamic tournaments from the perspective of choking under pressure. Using data from 127 international segregated-gender single and mixed-gender pair figure skating competitions organized by the International Staking Union from 1 July 2006 to 30 June 2018, this study showed that female interim leaders in segregated-gender competitions are more likely to make mistakes in task executions under pressure-inducing circumstances than male interim leaders. However, in mixed-gender competitions, all of these gender-specific influences disappear. The findings contribute to the literature on mixed-gender competitions by providing new evidence on the positive impact of them, as well as expanding the literature on the impact of gender on competitive pressure.


Assuntos
Obstrução das Vias Respiratórias , Desempenho Atlético , Comportamento Competitivo , Feminino , Humanos , Masculino , Movimento
17.
Sci Med Footb ; 6(2): 181-188, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35475738

RESUMO

PURPOSE: Outscoring opponents is the primary goal in football. To optimise goal scoring opportunities (GSOs), it is important to understand the preceding physical and tactical performance. This observational study explored whether running behaviour prior to GSOs related to the subsequent outcome (goal or no goal) or contextual factors. METHODS: Tracking data was collected from one professional team during its 2016/2017 season. Physical output was differentiated for attacking styles and analysed for attackers (taking shots) and defenders (trying to prevent shots). RESULTS: Counter attacks were found most effective, as outcomes improved with fewer defenders behind the ball (r=-0.27; p=0.03). Offensively, running behaviour in the minute prior to GSOs explained most variance and increased activities correlated with success (r=0.26; p=0.04). Moreover, decreased high-intensity distances covered during matches significantly correlated with favourable outcomes (r=-0.21; p=0.02). Finally, increased attacking effectiveness was found to relate to greater defensive covered distances (r=0.51; p<0.01). DISCUSSION: Running behaviour prior to GSOs was found to relate to the subsequent outcome. Specifically, space ahead of attackers, forcing defenders to cover more ground, was found to relate to GSO effectiveness. The running behaviour of attackers was found unrelated to previous activity, highlighting the significance of physical capacity and well-timed substitutions.


Assuntos
Desempenho Atlético , Futebol Americano , Futebol , Comportamento Competitivo , Equipamentos Médicos Duráveis , Humanos
18.
Neural Netw ; 150: 364-376, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35358886

RESUMO

In a competitive game scenario, a set of agents have to learn decisions that maximize their goals and minimize their adversaries' goals at the same time. Besides dealing with the increased dynamics of the scenarios due to the opponents' actions, they usually have to understand how to overcome the opponent's strategies. Most of the common solutions, usually based on continual learning or centralized multi-agent experiences, however, do not allow the development of personalized strategies to face individual opponents. In this paper, we propose a novel model composed of three neural layers that learn a representation of a competitive game, learn how to map the strategy of specific opponents, and how to disrupt them. The entire model is trained online, using a composed loss based on a contrastive optimization, to learn competitive and multiplayer games. We evaluate our model on a pokemon duel scenario and the four-player competitive Chef's Hat card game. Our experiments demonstrate that our model achieves better performance when playing against offline, online, and competitive-specific models, in particular when playing against the same opponent multiple times. We also present a discussion on the impact of our model, in particular on how well it deals with on specific strategy learning for each of the two scenarios.


Assuntos
Comportamento Competitivo , Reforço Psicológico , Aprendizagem
19.
Nature ; 603(7902): 661-666, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35296863

RESUMO

Competitive interactions have a vital role in the ecology of most animal species1-3 and powerfully influence the behaviour of groups4,5. To succeed, individuals must exert effort based on not only the resources available but also the social rank and behaviour of other group members2,6,7. The single-cellular mechanisms that precisely drive competitive interactions or the behaviour of social groups, however, remain poorly understood. Here we developed a naturalistic group paradigm in which large cohorts of mice competitively foraged for food as we wirelessly tracked neuronal activities across thousands of unique interactions. By following the collective behaviour of the groups, we found neurons in the anterior cingulate that adaptively represented the social rank of the animals in relation to others. Although social rank was closely behaviourally linked to success, these cells disambiguated the relative rank of the mice from their competitive behaviour, and incorporated information about the resources available, the environment, and past success of the mice to influence their decisions. Using multiclass models, we show how these neurons tracked other individuals within the group and accurately predicted upcoming success. Using neuromodulation techniques, we also show how the neurons conditionally influenced competitive effort-increasing the effort of the animals only when they were more dominant to their groupmates and decreasing it when they were subordinate-effects that were not observed in other frontal lobe areas. Together, these findings reveal cingulate neurons that serve to adaptively drive competitive interactions and a putative process that could intermediate the social and economic behaviour of groups.


Assuntos
Comportamento Competitivo , Ecologia , Animais , Comportamento Competitivo/fisiologia , Alimentos , Giro do Cíngulo/fisiologia , Camundongos , Neurônios/fisiologia , Comportamento Social
20.
J Anim Ecol ; 91(5): 958-969, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35262914

RESUMO

Sexual dimorphism is a ubiquitous source of within-species variation, yet the community-level consequences of sex differences remain poorly understood. Here, we analyse a bitrophic model of two competing resource species and a sexually reproducing consumer species. We show that consumer sex differences in resource acquisition can have striking consequences for consumer-resource coexistence, abundance and dynamics. Under both direct interspecific competition and apparent competition between two resource species, sexual dimorphism in consumers' attack rates can mediate coexistence of the resource species, while in other cases can lead to exclusion when stable coexistence is typically expected. Slight sex differences in total resource acquisition also can reverse competitive outcomes and lead to density cycles. These effects are expected whenever both consumer sexes require different amounts or types of resources to reproduce. Our results suggest that consumer sexual dimorphism, which is common, has wide-reaching implications for the assembly and dynamics of natural communities.


Assuntos
Comportamento Competitivo , Caracteres Sexuais , Animais , Ecossistema , Feminino , Masculino , Modelos Biológicos , Dinâmica Populacional
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