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1.
Int J Sports Physiol Perform ; : 1-7, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39265977

RESUMEN

PURPOSE: This study aimed to assess the effect of playing different pick-and-roll (PnR) defensive tactical options during small-sided games (SSGs) on external and internal loads in female basketball players. METHODS: Twelve female basketball players (age 28 [2] y; stature 175 [6] cm; body mass 65 [7] kg; playing experience 18 [4] y) belonging to a team competing in the Lithuanian second division were recruited for this study. Across 3 experimental sessions and in a randomized order, players performed 3 SSGs sharing the same features but using 3 defensive strategies on the middle PnR action: Switch, Trap, and Drop. External load was measured using PlayerLoad (PL); the number of accelerations, decelerations, and changes of direction, classified based on their intensities as low (<2.5 m·s-2), medium (2.5-3.5 m·s-2), and high (>3.5 m·s-2); and jumps categorized as low (<40 cm) and high (≥40 cm). Internal load was measured via rating of perceived exertion (RPE). RESULTS: Higher PL values in SSGs including Trap defense were found compared with Drop (P < .001, ES = 0.69, moderate) and Switch (P = .001, ES = 0.60, moderate). Additionally, a higher number of accelerations was registered in Trap defense compared with Drop defense (P = .027, ES = 0.99, moderate). Trap defense also led to higher RPE compared with Switch (P = .003, ES = 1.49, large) and Drop (P = .004, ES = 1.42, large) defense. CONCLUSIONS: Different defensive strategies on the middle PnR can influence the external and internal loads during SSGs, and female basketball coaches should consider the high demand of the Trap defense when designing SSGs.

2.
Artículo en Ruso | MEDLINE | ID: mdl-39269292

RESUMEN

A literature review in PubMed and Google databases was performed. Inclusion criteria: randomized clinical trials, meta-analyses and systematic reviews, relevant full-text articles on metabolic syndrome (MS) in patients with schizophrenia. Exclusion criteria: articles of poor quality. The terminology of the article corresponds to that used in the publications included in the review. The review substantiates the relevance of the problem of MS, discloses the concept and discusses its criteria, provides data on the prevalence of MS in patients with schizophrenia, discusses the relationship between MS and schizophrenia, MS and cognitive impairment in schizophrenia, and describes metabolic changes in patients with a first episode of psychosis or early stage schizophrenia. Recommendations on therapeutic tactics in the development of metabolic syndrome in patients with schizophrenia are given.


Asunto(s)
Síndrome Metabólico , Esquizofrenia , Humanos , Síndrome Metabólico/epidemiología , Síndrome Metabólico/complicaciones , Esquizofrenia/complicaciones , Prevalencia , Disfunción Cognitiva/etiología
3.
Artículo en Inglés | MEDLINE | ID: mdl-39171481

RESUMEN

In many species, individuals of the same sex exhibit different mating behaviours, a phenomenon known as alternative mating tactics (AMTs). These AMTs may occur in species in which morphology prevents individuals from adopting different tactics (fixed expression of AMTs) as well as in species in which individuals can alternate between them (flexible expression of AMTs). Regardless of the way different mating tactics are expressed, a key point to understanding the selective forces driving AMT evolution relies on identifying differences in the reproductive success between tactics. Empirical studies often indicate that individuals adopting the main tactic (generally the more aggressive) have higher mating success than those adopting the secondary tactic. However, while this is expected for species showing flexible expression of AMTs, the same should not hold for species showing fixed expression of AMTs. In species with fixed expression of AMTs, individuals adopting each tactic have morphological specialisations in acquiring mates that may be responsible for eliminating differences in reproductive success between tactics. Despite such expectations, a comprehensive investigation across species regarding differences in the reproductive success of AMTs is lacking. Using a meta-analytical approach, we investigated if there is a difference in the reproductive success between tactics and whether this difference is related to how these tactics are expressed (fixed or flexible). We focused on males since information on reproductive success for females with AMTs is still scarce. We hypothesised that (i) males adopting the main tactic have higher reproductive success than males adopting the secondary tactic, and (ii) the difference in reproductive success between tactics will be higher in species with flexible rather than fixed expression of AMTs. When all species were pooled, we found that males adopting the main tactic had a similar reproductive success to males adopting the secondary mating tactic. However, this trend changed between species with fixed and flexible expression of AMTs. In species with flexible expression of AMTs, males exhibiting the main tactic have higher mating success than those adopting secondary tactics, while in species with fixed expression of AMTs, males adopting distinct tactics have similar reproductive success. Thus, the widespread assumption that males adopting the main tactic have higher reproductive success than males adopting the secondary tactic may be restricted to species in which individuals can alternate between tactics during their lifespan. However, we found that most data on the reproductive success of males adopting AMTs is restricted to short reproductive windows and may not reflect differences in lifetime reproductive success between tactics. Therefore, we highlight the importance of examining the selective pressures associated with fixed and flexible expression of AMTs on lifetime reproductive success to attain a deeper understanding of AMT evolution.

4.
J Sports Sci ; : 1-9, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39172868

RESUMEN

A tiebreak in tennis is one of the critical moments where players are expected to excel under mental pressure and maintain high level of performance. Despite the importance of tiebreak points, research exploring the performance of male and female players during such match phrase remains limited. This study aimed to investigate i) the overall tiebreak performance of male and female players in relation to the outcome, ii) to examine their point-level performance by considering different contextual variables. A total of 535 tiebreaks comprising 6380 points from the 2016-2021 US Open men's and women's singles matches were collected. The difference in match performance between winning and losing players within the entire tiebreak game was explored. A subsequent decision tree analysis was then used to analyse the effect of the contextual and performance variables on tiebreak point-by-point outcome. The results showed that male and female Winning players outperformed the Losing players in 1st Serve, Serve Width and Net approach performance. The analysis of point-level performance showed that Net point, Score scene, and Point server substantially impacted tennis players' tiebreak outcome. These findings provide valuable insight for coaches and players, informing tiebreak tactics tailoring and training in relevance to different match status.

5.
Environ Manage ; 74(4): 623-635, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39102053

RESUMEN

Complexity, uncertainty, and conflict characterize contemporary environmental challenges. Addressing these issues is beyond the purview of any one actor. A collaborative approach to environmental management is required; participation in collaboration is needed. However, participation in collaborative environmental management is a persistent challenge in practice. This research examines tactics used to engender participation in collaborations. Tactics constitute a strategy for communications with an intended goal and encompass the framing (i.e., wording, imagery) and platform of dissemination. This research examined the influence of tactics on an intention to participate in an environmental management collaboration. Eight tactics were empirically tested on 300 individuals aged 18-29. Descriptive and inferential statistical analysis was undertaken. Results uncovered the effectiveness of contextual and personal framings in engendering participation and deepened the understanding about past participation, tactics, and an individual's intention to participate. Opportunities to engender participation in collaborations using tactics are abundant. The research emphasizes the need for greater attention to tactics in environmental management and contributes to a greater understanding of tactics, identifying effective practices for engendering participation and broad dissemination.


Asunto(s)
Conservación de los Recursos Naturales , Conducta Cooperativa , Intención , Humanos , Conservación de los Recursos Naturales/métodos , Adulto , Adulto Joven , Adolescente , Masculino , Femenino , Comunicación
6.
Biol Lett ; 20(7): 20240139, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39046288

RESUMEN

Individuals foraging in groups face increased competition but can benefit from social information on foraging opportunities that can ultimately increase survival. Personality traits can be associated with food-finding strategies, such as shyer individuals scrounging on the food discoveries of others. How personality and foraging strategy interact in a social foraging context with different group compositions received less attention. Here, we conducted experiments to investigate the relationship between exploratory personality, group size (1-4 birds) and foraging success (i.e. speed of finding a food patch) in wild-caught red knots. We found that faster explorers, when foraging alone, discover food patches quicker than slower explorers. In groups, however, slower-exploring birds became quicker at finding food than fast explorers. This shows that slower-exploring individuals benefit from group foraging. They seem to be more perceptive to social cues, and in contrast to faster explorers, they become quicker at finding food when they are in a group than when foraging alone. We discuss how individuals with different personalities and foraging strategies can coexist in a social foraging context with different costs and benefits associated with their strategies.


Asunto(s)
Conducta Alimentaria , Conducta Social , Animales , Conducta Exploratoria , Personalidad , Masculino
7.
Res Q Exerc Sport ; : 1-10, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38980757

RESUMEN

The objective was to assess and compare the tactical conduct of players aged U-8, U-10, and U-12 during full- and small-sided games, focusing on tactical modeling and interaction dynamics. Each age group comprised three teams (n = 180; 60 per category; 20 per team), engaging in a tournament where teams faced each other once in both formats - 18 matches; 3 per category in each format. Full-sided games (GK + 10 vs.10 + GK; 100 × 68 m) and small-sided games (U-8: GK + 4 vs. 4 + GK (36 × 20 m); U-10: GK + 7 vs. 7 + GK (52.5 × 34 m); U-12: GK + 10 vs. 10 + GK (68 × 45 m). Standard playing times (3 periods of 12 minutes (U-8s); 3 periods of 15 minutes (U-10s); and 3 periods of 20 minutes (U-12s), with a 5-minute break. Variables were examined using descriptive analysis (mean, standard deviation, and confidence interval), with paired t-tests and Wilcoxon tests employed for inter-format comparisons. Despite players benefiting from more time and space in full-sided games (increased ball receptions and overall ball involvement), results from small-sided games indicate three key advantages: 1) More goals (U-8s: z = -3.44, p = .050) and shots on target (U-8: z = -3.25, p = .001; U-10: z = -2.72, p = .007); 2) Game space management-ball circulation in larger amplitude (U-10: t = -4.20, p = .001; U-12: t = -4.35, p < .001); and with more transitions (U-10: t = -3.60, p = .002; U-12: t = -4.16, p = .001) and 3) Fast decision-making-larger ball velocity circulation (U-08: t = -3.54, p = .003; U-10: t = -5.13, p < .001; U-12: t = -5.80, p < .001).

8.
Trends Ecol Evol ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38955568

RESUMEN

It is often argued that anisogamy causes alternative reproductive tactics (ARTs) to be more common in males than females. We challenge this view by pointing out logical flaws in the argument. We then review recent work on the diversity of female ARTs, listing several understudied types such as solitary versus communal breeding and facultative parthenogenesis. We highlight an important difference between male and female ARTs that caused female ARTs to be overlooked: male ARTs tend to focus on successful fertilization, whereas female ARTs occur at many stages of reproduction and often form complex networks of decision points. We propose to study correlated female ARTs as a whole to better understand their drivers and eco-evolutionary dynamics.

9.
Sports (Basel) ; 12(7)2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39058087

RESUMEN

Performance analysis in sports is a rapidly evolving field, where academics and applied performance analysts work together to improve coaches' decision making through the use of performance indicators (PIs). This study aimed to provide a comprehensive analysis of factors affecting running performance (RP) in soccer teams, focusing on low (LI), medium (MI), and high-speed distances (HI) and the number of high-speed runs (NHI). Data were collected from 185 matches in the Turkish first division's 2021-2022 season using InStat Fitness's optical tracking technology. Four linear mixed-model analyses were conducted on the RP metrics with fixed factors, including location, team quality, opponent quality, ball possession, high-press, counterattacks, number of central defenders, and number of central forwards. The findings indicate that high-press and opponent team quality affect MI (d = 0.311, d = 0.214) and HI (d = 0.303, d = 0.207); team quality influences MI (d = 0.632); location and counterattacks impact HI (d = 0.228, d = 0.450); high-press and the number of central defenders affects NHI (d = 0.404, d = 0.319); and ball possession affects LI (d = 0.287). The number of central forwards did not influence any RP metrics. This study provides valuable insights into the factors influencing RP in soccer, highlighting the complex interactions between formations and physical, technical-tactical, and contextual variables. Understanding these dynamics can help coaches and analysts optimize team performance and strategic decision making.

10.
Trials ; 25(1): 415, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38937798

RESUMEN

BACKGROUND: Randomized controlled trials (RCTs) are rigorous scientific research designs for evaluating intervention effectiveness. However, implementing RCTs in a real-world context is challenging. To develop strategies to improve its application, it is essential to understand the strengths and challenges of this design. This study thus aimed to explore the strengths, challenges, and strategies for improving the implementation of a pragmatic multicenter, prospective, two-arm RCT evaluating the effects of the Personalized Citizen Assistance for Social Participation (Accompagnement-citoyen Personnalisé d'Intégration Communautaire: APIC; weekly 3-h personalized stimulation sessions given by a trained volunteer over a 12-month period) on older adults' health, social participation, and life satisfaction. METHODS: A multiple case study was conducted with 14 participants, comprising one research assistant, seven coordinators, and six managers of six community organizations serving older adults, who implemented the APIC in the context of a RCT. Between 2017 and 2023, qualitative data were extracted from 24 group meetings, seven semi-directed interviews, emails exchanged with the research team, and one follow-up document. RESULTS: Aged between 30 and 60 (median ± SIQR: 44.0 ± 6.3), most participants were women from organizations already offering social participation interventions for older adults and working with the public sector. Reported strengths of this RCT were its relevance in assessing an innovative intervention to support healthy aging, and the sharing of common goals, expertise, and strategies with community organizations. Challenges included difficulties recruiting older adults, resistance to potential control group assignments, design complexity, and efforts to mobilize and engage volunteers. The COVID-19 pandemic lockdown and health measures exacerbated challenges related to recruiting older adults and mobilizing volunteers and complicated delivery of the intervention. The strategies that mostly overcame difficulties in recruiting older adults were reducing sample size, simplifying recruitment procedures, emphasizing the health follow-up, extending partnerships, and recognizing and supporting volunteers better. Because of the lockdown and physical distancing measures, the intervention was also adapted for remote delivery, including via telephone or videoconferencing. CONCLUSION: Knowledge of the strengths and challenges of pragmatic RCTs can contribute to the development of strategies to facilitate implementation studies and better evaluate health and social participation interventions delivered under real-life conditions. TRIAL REGISTRATION: NCT03161860; Pre-results. Registered on May 22, 2017.


Asunto(s)
Participación Social , Humanos , Femenino , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto , Voluntarios , Proyectos de Investigación , COVID-19/epidemiología , Ensayos Clínicos Controlados Aleatorios como Asunto , Ensayos Clínicos Pragmáticos como Asunto , Anciano , Satisfacción Personal , Estudios Multicéntricos como Asunto
11.
Br J Sociol ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38890782

RESUMEN

Sociohistorical research suggests that religious discourses and practices have been powerful in producing disciplined lines of conduct. Typically, however, this work has only considered the long-term consequences of discursive shifts or the one-sided outcomes of disciplinary practices. In contrast, this paper shows how the creative appropriation of disciplinary devices can instigate their transfiguration into additional disciplinary tools. By examining manuals for confession published in Counter-Reformation Italy, I identify three tactics via which believers allegedly approached Sacramental Penance as an impression management tool. The authors of these cultural objects detected the diffusion of these tactics and circulated their depictions to alert confessors and stigmatize believers who enacted them. These findings suggest that the theorizing of disciplining processes has to consider how the tactical appropriation of disciplinary practices can trigger processes of refraction via which their negative representations are reified and circulated as further disciplinary tools.

12.
Sci Med Footb ; : 1-20, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38940239

RESUMEN

OBJECTIVES: The main objectives of this scoping review were to conduct a systematic search on the physical, technical and tactical demands of rugby league training, consolidate and summarise key findings and identify any existing gaps in knowledge. METHODS: A systematic online search of Scopus, PubMed, MEDLINE and SPORTDiscus was conducted from earliest record to 6 August 2023 and supplemented by manually searching reference lists. The Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) Checklist was followed. Studies were eligible for inclusion if they investigated the physical, technical and/or tactical demands of rugby league training within all levels of competition and included either male or female participants. RESULTS: The initial search yielded 637 papers, 25 of which were included in the review. Of these studies, the majority (n = 19) exclusively examined the physical demands of training, one paper exclusively examined the technical demands of training, five studies included both physical and technical demands, and no studies examined the tactical demands of training. Small-sided games was the most prevalent drill included within investigations examining the physical and technical demands of various rugby league training drills. CONCLUSIONS: The present review was the first to scope peer-reviewed literature on the multifaceted demands (i.e. physical, technical and tactical) demands of rugby league training. It is apparent that this area is under researched, specifically in literature examining the technical and tactical elements of rugby league training.


Of the available literature examining the multifaceted demands of rugby league training, the majority investigated the physical demands, with a peak of four publications in 2012 and 2022 and an average number of one to two publications per year since its introduction (i.e. 2010). There is only a small number of studies available investigating the technical demands of rugby league training.While research has identified the importance of tactics to successful rugby league performance, there has been no investigations on the tactical demands within rugby league training. Accordingly, it is unknown how coaches meet their tactical objectives within training drills and training design to prepare for competition.There is a clear gap in research investigating the technical and tactical demands of rugby league training as well as the absence of team-based training drills included within available studies investigating the physical demands. Accordingly, future investigations should prioritise incorporating these elements within their research design.

13.
J Sports Sci Med ; 23(2): 358-365, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38841631

RESUMEN

Mixed-Team-Relay (MTR) triathlon is a novel Olympic discipline whose performance determinants and tactical behaviors have barely been studied. Additionally, a regulatory change has been made to the male and female relay order for the Paris 2024 Olympics. Therefore, this study aimed to determine the performance determinants and race dynamics as a function of competitive level on the new regulated MTR triathlon. Results from 129 national teams, (516 elite triathletes) across five MTR World Triathlon Series and two MTR European Championships in 2022 and 2023, were analyzed. Split times, average speeds, time behind the race leader (gap), partial and finishing positions, pack position as well as the rank positions of every segment, relay leg, and overall race were computed. Decision tree analyses were conducted as a predictive method for the overall results, and correspondence analyses were conducted to examine the relationship between the different relay legs and segments and the finishing positions. The performance of the fourth leg was the most relevant for overall result (30%), as well as the fourth running leg (16%) and the female legs performance (7%). Medallist relay teams were characterized by displaying a differential speed lower than 0.5 and 0.83 km/h, respectively, from the best-ranking athletes in the Legs 1 and 4. Furthermore, staying in the front pack after the second swimming leg showed a great relationship with achieving a medal position. New MTR triathlon rules shift race dynamics, emphasizing individual efforts in cycling and swimming, while maintaining the crucial importance of running.


Asunto(s)
Rendimiento Atlético , Ciclismo , Conducta Competitiva , Carrera , Natación , Humanos , Rendimiento Atlético/fisiología , Masculino , Ciclismo/fisiología , Femenino , Carrera/fisiología , Natación/fisiología , Conducta Competitiva/fisiología , Deportes de Equipo
14.
Nanomicro Lett ; 16(1): 214, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38869734
15.
Behav Sci (Basel) ; 14(6)2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38920812

RESUMEN

This review aims to map studies on governmental and institutional decision-making processes in emergencies. The literature reveals various approaches used by governments in managing emergencies. Consequently, this article suggests the need for a systematic literature review to outline how institutional decision-makers operate during emergencies. To achieve this goal, the most widely used databases in psychological research were consulted, with a specific focus on selecting scientific articles. Subsequently, these studies were rigorously assessed for their relevance using a structured literature selection process following the PRISMA 2020 guidelines. At the conclusion of the review process, nine studies were identified, each suggesting different methods by which governments manage emergencies. This diversity arises because emergency decision-making processes must account for numerous variables that change depending on the type of crisis and the specific context. However, several critical aspects have emerged, such as the centrality of pre-disaster planning to improve intervention practices and methods, attention to information gaps that inevitably arise during an emergency, and the importance of streamlining and delegating decision-making to emergency responders in the field to counter the phenomenon of centralized decision-making that often hampers crucial interventions during emergencies.

16.
J Funct Morphol Kinesiol ; 9(2)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38804454

RESUMEN

The game of soccer is complex and unpredictable, demanding multifaceted strategies for success. Performance analysis has evolved, focusing on key performance indicators (KPIs) to determine the factors that most significantly influence a team's success or failure during matches. Traditional performance analysis methods have emphasized quantifiable data like physical exertion and basic play events but often neglected the subtler tactical dimensions that could significantly impact game outcomes. This study aimed to fill the gap in the current literature by creating a comprehensive framework that incorporates tactical situations as KPIs. The objective was to examine whether specific playing styles adopted by teams in various tactical situations and phases of the game could predict the outcome of matches. A dataset comprising all First Division Championship matches from 11 different European countries for the 2021-2022 season was analyzed. Variables representing tactical situations were correlated with match outcomes using a Generalized Estimating Equation framework. The model was specified with a binomial distribution and a logit link function. Statistical significance was determined using Wald χ2 tests with a significance level set at p < 0.05. The study's findings revealed that possession style, counterattacking during offensive transitions, and a balanced aggressive defensive strategy significantly increase a team's chances of victory. It also showed that successful teams tend to focus on central attacks, minimize crossing, and execute strategic plays that lead to final attempts on goal with minimal ball possession. The above findings demonstrate that adopting certain tactical approaches significantly influences soccer match outcomes, highlighting the importance of considering tactical aspects as KPIs.

17.
Wiad Lek ; 77(3): 597-601, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38691806

RESUMEN

OBJECTIVE: Aim: Analyzing of the last-time papers in this subject in organizing, diagnostic and surgery tactic is the aim of this work. PATIENTS AND METHODS: Materials and Methods: The study analyzed the experience of treating patients with maxillofacial polytrauma before and after February 24, 2022. Research methods: bibliographic, systematic, comparative, general clinical, radiological and retrospective analysis. CONCLUSION: Conclusions: Tactic of the multidisciplinal team should based on the principles of damage control, which involves the initial performance of manipulations and surgical interventions that ensure the patient's survival. Modern strategies for infusion-transfusion therapy play a significant role in severe trauma cases. Choosing the rational management of this therapy for severe trauma remains an important issue. Reconstructive surgeries are recommended to be performer deferred, after surgical wound management, neurosurgical interventions and stabilization of the patient common status. Patients with maxillofacial polytrauma needs in specialized medical care at all the levels. Active wound management aimed at creating favorable conditions for healing, comprehensive medical treatment, prevention, early detection and timely treatment of complications.


Asunto(s)
Traumatismos Maxilofaciales , Traumatismo Múltiple , Humanos , Traumatismos Maxilofaciales/cirugía , Traumatismos Maxilofaciales/terapia , Traumatismo Múltiple/terapia , Traumatismo Múltiple/cirugía , Procedimientos de Cirugía Plástica/métodos
18.
J Hum Kinet ; 92: 239-249, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38736595

RESUMEN

The purpose of the study was to analyze the influence of left-handed athletes on the opponent (right-handed players) of elite badminton women's singles. The study selected a total of 40 women's singles matches played by elite female players: twenty matches (42 games, n = 42) were played between left-handed and right-handed players and twenty matches (44 games, n = 44) were played between two right-handed players. There were significant (p < 0.05) differences in hitting positions, techniques, routes and landing points. No significant (p > 0.05) differences were found in scores per game and frequency distribution of rally outcomes. In conclusion, the details of technical and tactical application were different in two game forms, the main impact of the left-handed player on the opponent's (right-handed player) game was a decrease in the opponent's stroke in the overhead, an increase in the number of drives, predominance of small slashes and a decrease in big slashes.

19.
Sci Rep ; 14(1): 11702, 2024 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-38777827

RESUMEN

In some squids, such as those in the family Loliginidae, upon copulation, females receive and store male-delivered sperm capsules, spermatangia, at two different body locations: the buccal membrane and the distal end of the oviduct. This insemination site dimorphism is associated with alternative reproductive strategies. However, in Loliolus sumatrensis, a species of Loliginidae, the females possess three insemination sites: buccal membrane (BM), basal left IV arm (ARM) and lateral head behind the left eye (EYE), therefore we studied such the unusual phenomena. We developed microsatellite markers and genotyped the paternity of each spermatangium on three sites. We found multiple paternity at every single site and simultaneous usage of all three sites by a few males. The seasonal dynamics of a population in the Seto Inland Sea revealed a set priority for the initial use of insemination sites as BM, followed by ARM and then EYE, whereas the maximum number of stored spermatangia was greater in EYE > ARM > BM. Female maturity status was correlated with the usage pattern of insemination sites but not with the number of stored spermatangia at any insemination site. These results suggest that a male squid inseminates at different locations according to female mating history and female maturity status.


Asunto(s)
Decapodiformes , Repeticiones de Microsatélite , Animales , Femenino , Masculino , Decapodiformes/fisiología , Decapodiformes/genética , Repeticiones de Microsatélite/genética , Conducta Sexual Animal/fisiología , Inseminación , Reproducción/fisiología , Genotipo , Copulación/fisiología
20.
Biol Open ; 13(6)2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38738657

RESUMEN

Trait polymorphisms are widespread in nature, and explaining their stable co-existence is a central problem in ecology and evolution. Alternative reproductive tactics, in which individuals of one or more sex exhibit discrete, discontinuous traits in response to reproductive competition, represent a special case of trait polymorphism in which the traits are often complex, behavioural, and dynamic. Thus, studying how alternative reproductive tactics are maintained may provide general insights into how complex trait polymorphisms are maintained in populations. We construct a spatially explicit individual-based model inspired from extensively collected empirical data to address the mechanisms behind the co-existence of three behavioural alternative reproductive tactics in males of a tree cricket (Oecanthus henryi). Our results show that the co-existence of these tactics over ecological time scales is facilitated by the spatial structure of the landscape they inhabit, which serves to equalise the otherwise unequal mating benefits of the three tactics. We also show that this co-existence is unlikely if spatial aspects of the system are not considered. Our findings highlight the importance of spatial dynamics in understanding ecological and evolutionary processes and underscore the power of integrative approaches that combine models with empirical data.


Asunto(s)
Gryllidae , Reproducción , Conducta Sexual Animal , Masculino , Gryllidae/fisiología , Gryllidae/genética , Animales , Evolución Biológica , Fenotipo
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