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Bluetongue is a non-zoonotic arboviral disease transmitted by biting midges of the genus Culicoides. Among 1,347 Culicoides species, 30 are known to be vectors of the disease. Bluetongue affects domestic and wild ruminants across all continents, except the Antarctica, causing growing economic losses in livestock production and international trade. In this work, we focused on potential mechanisms underlying the bluetongue virus emergence and spread. Of these mechanisms, the emergence of novel serotypes makes vaccination controversial despite its effectiveness, along with the vector's ability to acquire the virus and successfully transmit it, spatio-temporal adaptation, and identification of new transmission routes. We also discussed the predisposition of the vertebrate and invertebrate hosts to contract the virus, as well as factors hijacking vector population activity and abundance. Indeed, the ecological dynamics of biting midges strongly influence the ability of the virus to be transmitted and to cause epizootic into parts of the world never before affected, helped by interactions between the pathogen and its host in addition to multiple routes deployed to escape defense barriers in the target infected cells. The points raised in this review can help inform aspects of interest for future studies that may elucidate factors to consider in monitoring and controlling the expansion of Culicoides -transmitted arboviruses. [ABSTRACT FROM AUTHOR]

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Bluetongue is a non-zoonotic arboviral disease transmitted by biting midges of the genus Culicoides. Among 1,347 Culicoides species, 30 are known to be vectors of the disease. Bluetongue affects domestic and wild ruminants across all continents, except the Antarctica, causing growing economic losses in livestock production and international trade. In this work, we focused on potential mechanisms underlying the bluetongue virus emergence and spread. Of these mechanisms, the emergence of novel serotypes makes vaccination controversial despite its effectiveness, along with the vector’s ability to acquire the virus and successfully transmit it, spatio-temporal adaptation, and identification of new transmission routes. We also discussed the predisposition of the vertebrate and invertebrate hosts to contract the virus, as well as factors hijacking vector population activity and abundance. Indeed, the ecological dynamics of biting midges strongly influence the ability of the virus to be transmitted and to cause epizootic into parts of the world never before affected, helped by interactions between the pathogen and its host in addition to multiple routes deployed to escape defense barriers in the target infected cells. The points raised in this review can help inform aspects of interest for future studies that may elucidate factors to consider in monitoring and controlling the expansion of Culicoides-transmitted arboviruses.

Anticipation is key to performance in many sports. By definition, anticipation as a perceptual-cognitive process is meant to inform action and help athletes reduce potential motor costs under spatiotemporal pressure. Anticipation research has repeatedly been criticized for neglecting action and raised the need for predominant testing under conditions of perception-action coupling (PAC). To the best of our knowledge, however, there is a lack of explicit criteria to characterize and define PAC conditions. This can lead to blurred terminology and may complicate interpretation and comparability of PAC conditions and results across studies. Here, we make a first proposal for a 7-level classification of PAC conditions with the defining dimensions of stimulus presentation and response mode. We hope this classification may constitute a helpful orientation for study planning and reporting in research on anticipation. Further, we illustrate the potential utilization of the PAC classification as a template for experimental protocol analysis in a review on anticipation in racket sports. Analysis of N = 115 studies reported in N = 91 articles confirms an underrepresentation of representative PAC conditions and reveals little change in PAC approaches over more than 40years of research in that domain. We discuss potential reasons for these findings, the benefits of adopting the proposed PAC classification and reiterate the call for more action in anticipation research. [ABSTRACT FROM AUTHOR]

Motivation: The intrinsic characteristics of islands make them a unique study system for the investigation of ecological and evolutionary dynamics. The Mediterranean Basin, an island‐rich biodiversity hotspot, still lacks a comprehensive spatial database for these geographic features. This study presents the first comprehensive spatial database of all Mediterranean islands larger than 0.01 km2, aiding ecological investigations and interdisciplinary research. Main types of variable contained: The MEDIS spatial database offers detailed information on 39 geographic, climatic, ecological and land‐use variables, including island area, perimeter, isolation metrics, climatic space, terrain data, land cover, palaeogeography, road networks and geological information, providing a multifaceted view of each island's characteristics. Spatial location and grain: The study encompasses 2217 islands in the Mediterranean Basin larger than 0.01 km2. The spatial grain of the datasets on which the selected variables are based varies from 10 m (ESA WorldCover) to 1 km (CHELSA‐BIOCLIM+). Time period and grain: The spatial database incorporates data from various sources, each with its own timeframe, such as the Global Shoreline Vector from 2014 Landsat imagery and the WorldCover dataset from 2021. Historical data like the Paleocoastlines GIS dataset offer insights into island configurations during the Last Glacial Maximum. Major taxa and level of measurement: While not focusing on specific taxa, the study lays the foundation for comprehensive research on Mediterranean islands, facilitating comparisons and investigations into the distribution of native, endemic or alien species. The level of measurement is extensive, encompassing a wide range of variables and providing polygonal features rather than centroids' coordinates. [ABSTRACT FROM AUTHOR]

Eco‐evolutionary experiments are typically conducted in semi‐unnatural controlled settings, such as mesocosms; yet inferences about how evolution and ecology interact in the real world would surely benefit from experiments in natural uncontrolled settings. Opportunities for such experiments are rare but do arise in the context of restoration ecology—where different "types" of a given species can be introduced into different "replicate" locations. Designing such experiments requires wrestling with consequential questions. (Q1) Which specific "types" of a focal species should be introduced to the restoration location? (Q2) How many sources of each type should be used—and should they be mixed together? (Q3) Which specific source populations should be used? (Q4) Which type(s) or population(s) should be introduced into which restoration sites? We recently grappled with these questions when designing an eco‐evolutionary experiment with threespine stickleback (Gasterosteus aculeatus) introduced into nine small lakes and ponds on the Kenai Peninsula in Alaska that required restoration. After considering the options at length, we decided to use benthic versus limnetic ecotypes (Q1) to create a mixed group of colonists from four source populations of each ecotype (Q2), where ecotypes were identified based on trophic morphology (Q3), and were then introduced into nine restoration lakes scaled by lake size (Q4). We hope that outlining the alternatives and resulting choices will make the rationales clear for future studies leveraging our experiment, while also proving useful for investigators considering similar experiments in the future. [ABSTRACT FROM AUTHOR]

IntroductionThis study aimed to verify whether implicit and explicit informational constraints generate differences in tactical performance and behavior in U-20 national-level soccer players.MethodsThirty-two under-20 male athletes from two clubs participated. Four 4-a-side small-sided games (SSG) protocols were used: R1 - explicit rule for high-press marking, R2 - implicit rule for high-press marking, R3 - game with both previous rules simultaneous and FR - free game, without additional rules. SSGs comprised 4 vs. 4+ goalkeepers games on a 42 m × 29 m field. Position data from 10 Hz Global Positioning System (GPS) devices were used to evaluate individual and collective tactical behavior (spatial occupation metrics) and performance (interpersonal coordination). MANOVA was used for normally distributed variables, and Friedman's with Dunn or Bonferroni post hoc was used for variables without normal distribution. For SEI, an ANOVA was used with Bonferroni post hoc.ResultsThe R1 protocol showed higher SEI, length, width, and LpWratio than the FR protocol (p = 0.009). There was an effect of the different protocols in SEI values (p

Introduction: This paper deals with the question on how sport performances may be influenced by internal, emotional processes, which stem from outside feedback. Methods: In terms of methods, players’ subjective performance ratings for four experimental auditory cue conditions were examined; these included both ‘positive’ and ‘negative’ stadium noise, ‘no (auditory) conditions,’ and a control/‘baseline’ condition. This resulted in a qualitative-analytic data set that was obtained succeeding each auditory cue condition using a unique football training machine (i.e., known as ‘Footbonaut’). Without having received any coaching/performance feedback, players were asked to rate and individually comment on their perceived performance ratings for each experimental auditory condition. Results: Findings indicate stronger and more significant correlations between auditory conditions and subjective ratings compared to the non-auditory condition and its subjective rating. Furthermore, data provides initial insight into players’ emotional experiences during each of the practice conditions. Discussion: These noteworthy findings on players’ abilities to accurately judge their performances based on selfmonitoring and intrinsic feedback are discussed from an Ecological Dynamics perspective, linked to a Nonlinear Pedagogy for coaching. Here, representative and affective learning designs for skill learning and performance preparation are presented. Finally, a hypothetical catalyst effect of auditory stadium noise on subjective performance rating is proposed. [ABSTRACT FROM AUTHOR]

Anticipation is key to performance in many sports. By definition, anticipation as a perceptual-cognitive process is meant to inform action and help athletes reduce potential motor costs under spatiotemporal pressure. Anticipation research has repeatedly been criticized for neglecting action and raised the need for predominant testing under conditions of perception-action coupling (PAC). To the best of our knowledge, however, there is a lack of explicit criteria to characterize and define PAC conditions. This can lead to blurred terminology and may complicate interpretation and comparability of PAC conditions and results across studies. Here, we make a first proposal for a 7-level classification of PAC conditions with the defining dimensions of stimulus presentation and response mode. We hope this classification may constitute a helpful orientation for study planning and reporting in research on anticipation. Further, we illustrate the potential utilization of the PAC classification as a template for experimental protocol analysis in a review on anticipation in racket sports. Analysis of N = 115 studies reported in N = 91 articles confirms an underrepresentation of representative PAC conditions and reveals little change in PAC approaches over more than 40 years of research in that domain. We discuss potential reasons for these findings, the benefits of adopting the proposed PAC classification and reiterate the call for more action in anticipation research.

IntroductionThis paper deals with the question on how sport performances may be influenced by internal, emotional processes, which stem from outside feedback.MethodsIn terms of methods, players’ subjective performance ratings for four experimental auditory cue conditions were examined; these included both ‘positive’ and ‘negative’ stadium noise, ‘no (auditory) conditions,’ and a control/‘baseline’ condition. This resulted in a qualitative-analytic data set that was obtained succeeding each auditory cue condition using a unique football training machine (i.e., known as ‘Footbonaut’). Without having received any coaching/performance feedback, players were asked to rate and individually comment on their perceived performance ratings for each experimental auditory condition.ResultsFindings indicate stronger and more significant correlations between auditory conditions and subjective ratings compared to the non-auditory condition and its subjective rating. Furthermore, data provides initial insight into players’ emotional experiences during each of the practice conditions.DiscussionThese noteworthy findings on players’ abilities to accurately judge their performances based on selfmonitoring and intrinsic feedback are discussed from an Ecological Dynamics perspective, linked to a Nonlinear Pedagogy for coaching. Here, representative and affective learning designs for skill learning and performance preparation are presented. Finally, a hypothetical catalyst effect of auditory stadium noise on subjective performance rating is proposed.

This study aimed to compare the collective and individual tactical positional behavior before the first goal was scored or conceded in official soccer matches. The sample comprised 50 players and 27 official matches played in Brazil during the 2020 and 2021 U-20 seasons. Global Positioning System devices were used to monitor the players' positional data. Collective - width, length, length per width ratio, and stretching index, and individual - spatial exploration index, variables were calculated and compared between the contextual scenarios by a one-way ANOVA. Results indicated a reduction in the width after scoring a goal (p=.006) and a lower spatial exploration after conceding a goal (p<.001) compared with the draw condition. Therefore, it is concluded that goal-scoring affects the tactical positional responses of the players. Specifically, a higher width concentration, characteristic of defensive tactical behavior, is observed after scoring a goal to keep the current match status. On the other hand, players present difficulties in exploring the space after conceding a goal. The knowledge of these intrinsic game dynamics is helpful for coaches in preparing the strategies to explore changes due to goal scoring in official matches. [ABSTRACT FROM AUTHOR]

Designers of educational modules for conceptual learning often rely on procedural frameworks to chart out interaction mechanics through which users will develop target understandings. To date, however, there has been no systematic comparative evaluation of such frameworks in terms of their consequences for learning. This lack of empirical evaluation, we submit, is due to the intellectual challenge of pinning down in what fundamental sense these various frameworks differ and, therefore, along which parameters to conduct controlled comparative experimentation. Toward an empirical evaluation of educational-technology design frameworks, this conceptual paper considers the case of dynamic mathematics environments (DME), interactive modules for learning curricular content through manipulating virtual objects. We consider user activities in two paradigmatic DME genres that utilize similar HCI yet different mechanics. To compare these mechanics, we draw from complex dynamic systems theory a constraint-based model of embodied interaction. Task analyses suggest that whereas in one DME genre (GeoGebra) the interaction constraints are a priori inherent in the environment, in another DME genre (Mathematics Imagery Trainer) the constraints are ad hoc emergent in the task. We conjecture differential learning effects of these distinct constraint regimes, concluding that ad hoc emergent task constraints may better facilitate the naturalistic development of cognitive structures grounding targeted conceptual learning. We outline a future empirical research design to compare the pedagogical entailments of these two design frameworks.

Athletes act intentionally and adaptively for achieving task goals in sport performance environments. The ecological dynamics approach to decision making understands the performer‐environment system as the unit of analysis to understand behavior, where action is not just limited to processes occurring in the individual (e.g., information-processing theories) or in the environment (behaviorist approaches) but implies the close link between the two. In the present article we synthesize the key tenets of the ecological dynamics theoretical framework and describe how both individual and group decision-making in sport can be understood. We explain how behavior and decision-making are based upon self-organized processes, from which functional synergies emerge, paving the way for expert performance in individuals and groups. Specifically, considering group decision-making, we describe how team members are coordinated in the complex system that the team is. Finally, we suggest that the ecological dynamics approach is a well-suited framework to research individual and team cognition, with many applications to practice.

Abstract Inferring ecological interactions is hard because we often lack suitable parametric representations to portray them. Neural ordinary differential equations (NODEs) provide a way of estimating interactions non‐parametrically from time‐series data. NODEs, however, are slow to fit, and inferred interactions usually are not compared with the ground truth. We provide a fast NODE fitting method, Bayesian neural gradient matching (BNGM), which relies on interpolating time series with neural networks and fitting NODEs to the interpolated dynamics with Bayesian regularisation. We test the accuracy of the approach by inferring ecological interactions in time series generated by an ODE model with known interactions. We compare these results against three existing approaches for estimating ecological interactions, standard NODEs, ODE models and convergent cross‐mapping (CCM). We also infer interactions in experimentally replicated time series of a microcosm featuring an algae, flagellate and rotifer population, in the hare and lynx system, and the Maizuru Bay community featuring 11 species. Our BNGM approach allows us to reduce the fitting time of NODE systems to only a few seconds and provides accurate estimates of ecological interactions in the artificial system, as true ecological interactions are recovered with minimal error. Our benchmark analysis reveals that our approach is both faster and more accurate than standard NODEs and parametric ODEs, while CCM was found to be faster but less accurate. The analysis of the replicated time series reveals that only the strongest interactions are consistent across replicates, while the analysis of the Maizuru community shows the strong negative impact of the chameleon goby on most species of the community, and a potential indirect negative effect of temperature by favouring goby population growth. Overall, NODEs alleviate the need for a mechanistic understanding of interactions, and BNGM alleviates the heavy computational cost. This is a crucial step availing quick NODE fitting to larger systems, cross‐validation and uncertainty quantification, as well as more objective estimation of interactions, and complex context dependence, than parametric models.

Urban green planning is crucial in promoting sustainable urban ecosystems through the mindful use of vegetation, but few approaches are currently able to account for the ecosystem services provided by urban green planning in ex ante planning applications. The present research proposes a methodological approach to sustainable urban planning that accounts for the ecological role of vegetation in urban ecosystems. Indeed, by estimating the functions exerted by different vegetation elements in urban ecosystems through a purposely developed set of equations, the procedure allows for the optimization of the development of urban plans by maximizing the contribution of vegetation to ecosystem dynamics. Specifically, the proposed methodology is articulated in two phases, i.e., the functional role of vegetation is firstly modeled through simple geometric features and specific ecological traits accounting for plant interactions with the environment, and then the selected vegetation traits are used in guiding the choice of the species. The approach has been exemplified through case studies, thereby highlighting its ability to guide planning decisions based on the type, abundance, and spatial organization of vegetation to promote the sustainability of urban development. [ABSTRACT FROM AUTHOR]

Aims: Spatio‐temporal processes play a key role in ecology, from genes to large‐scale macroecological and biogeographical processes. Existing methods studying such spatio‐temporally structured data either simplify the dynamic structure or the complex interactions of ecological drivers. The aim of this paper is to present a generic method for ecological research that allows analysing spatio‐temporal patterns of biological processes at large spatial scales by including the time‐varying variables that drive these dynamics. Location: Global analysis at the level of 272 regions. Methods: We introduce a method called relational event modelling (REM). REM relies on temporal interaction dynamics that encode sequences of relational events connecting a sender node to a recipient node at a specific point in time. We apply REM to the spread of alien species around the globe between 1880 and 2005, following accidental or deliberate introductions into geographical regions outside of their native range. In this context, a relational event represents the new occurrence of an alien species given its former distribution. Results: The application of relational event models to the first reported invasions of 4835 established alien species outside of their native ranges from four major taxonomic groups enables us to unravel the main drivers of the dynamics of the spread of invasive alien species. Combining the alien species first records data with other spatio‐temporal information enables us to discover which factors have been responsible for the spread of species across the globe. Besides the usual drivers of species invasions, such as trade, land use and climatic conditions, we also find evidence for species‐interconnectedness in alien species spread. Conclusions: Relational event models offer the capacity to account for the temporal sequences of ecological events such as biological invasions and to investigate how relationships between these events and potential drivers change over time. [ABSTRACT FROM AUTHOR]

Metaphor is a useful way of explaining how to do things. The literature on metaphor in the learning of physical skill has generally explicated its efficacy by examining its actionable directives for motor enactment. And yet from the perspectives of phenomenological philosophy, ecological psychology, and enactivism, action is immanently intertwined with perception, so that models of metaphor-based learning should foreground the role of sensory activity modulating motor behavior. As such, metaphor is retheorized as a sensorial constraint one imaginarily projects into one’s action–perception phenomenological landscape. I present two metaphors from an instructional video on cello technique. Whereas these metaphors are couched in action language (what one should do), their potential impact, I argue, lies in emergent goal sensations (what one should feel). These explorative sensorimotor accommodations may, in turn, bring forth yet new scopes of latent sensations coupled to unanticipated performance possibilities, which suggest further modifying and calibrating enactment in the target domain. Attending to, achieving, and maintaining emergent intermediary goal sensations regulates instrumented action by forging new affordances that bring forth new motor coordination. As teacher and student co-imagine images for action, they should attend to sensory perceptions. And the same goes for scholars of metaphor.

Knowledge and knowledge transfer are often viewed in unitary and hierarchical terms, where a linear transaction exists between an individual possessing a body of knowledge and a person needing that knowledge. Although this traditional view of knowledge transfer is common within the sports domain, it is problematic because knowledge is treated as a self-contained entity. The overarching purpose of this study is to explore the ecological role of knowledge, underpinning performance preparation processes in an international coaching setting. Specifically, we investigated how bi-directional self-organising (coordination) tendencies (coach and athlete-led) can be exploited to facilitate the formation of attacking synergies within the team sport of wheelchair rugby league. A mixed-method case study approach was employed to collect data, involving semi-structured interviews, reflexive observations and field notes, and notational analysis. Results from the study described the transitional process of positioning an ecological view of knowledge transfer as a guiding principle to enhance athlete and practitioner collaboration. This reciprocal relationship provided documented opportunities to enhance on- and off-field team synergies. The pedagogical experiences we describe emerged throughout periods of uncertainty, requiring effortful interactions, forged on the continuous coupling of key agents (individuals), content, and context, enabling application, refinement, and opportunities for team synergies to evolve in performance preparation. Results suggested that the challenge of understanding and facilitating knowledge transfer could be embedded within the ecology of a complex adaptive system, sustained as a contextualised activity reciprocally constructed through on-going correspondence between athletes, scientists, practitioners, and the competitive performance context.

By implementing an insider action-research (AR) design throughout a competitive volleyball season, this study sought to examine qualitatively how competitive data, extracted from match analysis, may support the development of a coaching intervention based on the principles of the constraint-led approach. Twelve elite players, one head coach and one assistant coach participated in two AR cycles, each one involving the processes of planning, monitoring, reflecting, and fact-finding. The first author, who was also the assistant coach and the insider-researcher, collected data over 20 weeks using interviews, training videotaped records, and field notes. Data were analysed using thematic analysis, and inductive procedures were adopted to deepen an understanding of how a constraint-led coaching intervention evolved over the season. The results highlighted competitive data as a relevant tool for supporting the underlying pedagogical process in the design of representative learning tasks via constraints manipulation. Grounded on competitive data, the learning designs progressed from an initial point where constraints manipulation was scarce, non-representative, and without stimulating players' problem-solving abilities, to an endpoint where tasks were conceived based on the next opposition's features (i.e., task representativeness) and focused on the development of functional and co-adaptative skills. In conclusion, the competitive data supported the development of a coaching practice based on the constraint-led approach. Methodologically, the insider AR-design offered contextualized insights into how the pedagogical coaching intervention evolved over the season. Thus, we highlight the importance of sampling the most relevant information from competition, through match analysis reports, so that coaches can design representative and contextualized learning tasks ongoingly aligned with players' needs. [ABSTRACT FROM AUTHOR]

Athletes act intentionally and adaptively for achieving task goals in sport performance environments. The ecological dynamics approach to decision making understands the performer-environment system as the unit of analysis to understand behavior, where action is not just limited to processes occurring in the individual (e.g., information-processing theories) or in the environment (behaviorist approaches) but implies the close link between the two. In the present article we synthesize the key tenets of the ecological dynamics theoretical framework and describe how both individual and group decision-making in sport can be understood. We explain how behavior and decision-making are based upon self-organized processes, from which functional synergies emerge, paving the way for expert performance in individuals and groups. Specifically, considering group decision-making, we describe how team members are coordinated in the complex system that the team is. Finally, we suggest that the ecological dynamics approach is a well-suited framework to research individual and team cognition, with many applications to practice. [ABSTRACT FROM AUTHOR]

Inferring ecological interactions is hard because we often lack suitable parametric representations to portray them. Neural ordinary differential equations (NODEs) provide a way of estimating interactions non‐parametrically from time‐series data. NODEs, however, are slow to fit, and inferred interactions usually are not compared with the ground truth.We provide a fast NODE fitting method, Bayesian neural gradient matching (BNGM), which relies on interpolating time series with neural networks and fitting NODEs to the interpolated dynamics with Bayesian regularisation. We test the accuracy of the approach by inferring ecological interactions in time series generated by an ODE model with known interactions. We compare these results against three existing approaches for estimating ecological interactions, standard NODEs, ODE models and convergent cross‐mapping (CCM). We also infer interactions in experimentally replicated time series of a microcosm featuring an algae, flagellate and rotifer population, in the hare and lynx system, and the Maizuru Bay community featuring 11 species.Our BNGM approach allows us to reduce the fitting time of NODE systems to only a few seconds and provides accurate estimates of ecological interactions in the artificial system, as true ecological interactions are recovered with minimal error. Our benchmark analysis reveals that our approach is both faster and more accurate than standard NODEs and parametric ODEs, while CCM was found to be faster but less accurate. The analysis of the replicated time series reveals that only the strongest interactions are consistent across replicates, while the analysis of the Maizuru community shows the strong negative impact of the chameleon goby on most species of the community, and a potential indirect negative effect of temperature by favouring goby population growth.Overall, NODEs alleviate the need for a mechanistic understanding of interactions, and BNGM alleviates the heavy computational cost. This is a crucial step availing quick NODE fitting to larger systems, cross‐validation and uncertainty quantification, as well as more objective estimation of interactions, and complex context dependence, than parametric models. [ABSTRACT FROM AUTHOR]

Underpinned by an ecological dynamics rationale, the Learning in Development Research Framework (LDRF) has been suggested to introduce methodological possibilities to investigate and illuminate: (i) socio-cultural constraints within a sports organization or club, and (ii), a research gap on the need for a more contemporary framework to guide reliable ways of conducting investigations and designing practical applications. To provide a strong justification for the nature of the fieldwork and methods adopted, we present insights from a 3-year and 5-month study at a professional football club in Sweden that adapted the framework as a central feature of their Department of Methodology for player development. A phronetic iterative approach was employed to analyze the data. The findings highlight the nature of constraints acting over varied timescales, transcending contexts to manifest in other contexts (e.g., practice task designs), influencing events and experiences. This indicated a need to dampen (using probes) the influence of the pervasive organizational “control over context” approaches that were acting as “sticky” socio-cultural constraints, shaping the intentions (in session design) and attention (during practice and performance) of players and coaches. A practical implication is that the LDRF does not prescribe a universal solution to player development. Rather that it can guide how researchers, practitioners, clubs and organisations could challenge themselves to adapt strategies to design contemporary athlete development frameworks within their ecosystem.

BackgroundObservational tools can help refine practice design and guide the creation of effective learning environments. The intention of this study was to design and validate an observational instrument for assessing physical literacy that remains more faithful to the philosophically complex and holistic nature of the concept.MethodsFramed by concepts of ecological dynamics, the emergent games-based assessment tool enables capture of children's interactions with their environment, providing insight on the manifestation of physical literacy within physical education games. The design and validation of the instrument consisted of a multistage process: (1) design of the observational instrument and establishing face validity; (2) pilot observation study; (3) expert qualitative and quantitative review to establish content validity; (4) observation training; and (5), establishing observer reliability.ResultsFollowing expert qualitative and quantitative evaluation, Aiken's V coefficient was used to determine content validity. Results achieved demanding levels of validity (V ≥ 0.78) for all retained measurement variables. Cohen's κ values for inter- and intra-observer reliability ranged from 0.331 to 1.00 and 0.552 to 1.00, generally reporting “substantial” agreement during inter-observer analysis and “substantial” to “almost perfect” agreement during intra-observer analysis.ConclusionsThe final model of the emergent games-based assessment tool, with 9 ecological conceptualisations of behaviour, 15 measurement variables, and 44 categorical observational items was found to be valid and reliable, providing both educators and researchers with a useful mechanism to assess physical literacy during gameplay.

The target article promotes an enactive approach to human behaviour, highlighting the phenomenology of agent-environment coupling, and is rooted in the course of experience from pre-reflective self-consciousness. In our comment we debate the idea that experience does equate with subjectivity. Such an equation reflects an organismic asymmetry locating behavioural organisation in the subjective mind, interacting with the objective world. In contrast, an ecological realist perspective considers that human behaviour and experience should be captured at the ecological level of analysis, requiring investigation of eco-physical variables. To achieve this aim, researchers need to avoid organismic asymmetries, and instead study performance variables that underpin the symmetry of the agent-environment system. We also debate the place of language and the fact that verbalisation does not equate with subjective experience. According to James Gibson, language focuses on 'knowledge about the environment' and not 'knowledge of the environment' needed by any autonomous, self-regulating organism, making their way in the world. Last, the target paper promotes the course of in-formation to complement the course of experience, without fully explaining how to deal with potential incongruence and divergence between findings emerging from verbalisation and behavioural aspects of realizing a given activity (the difference between 'what we say, what we do'). We conclude by considering how our ecological perspective could offer pathways for the presented enactive approach to go beyond the course of in-formation. [ABSTRACT FROM AUTHOR]

The aim of this insights paper is to propose how the theory of ecological dynamics may invite re-consideration of how sport scientists could support performance, learning and development of children and youth in sports programmes. We seek to outline why learning should be individualised and contextualised, based on the specific needs of learners, such as children and youth, women and disabled athletes in sport. Case examples from individual and team sports are presented to illustrate how constraints can be designed to enrich interactions of children and youth with different performance environments, based on integrating principles of specificity and generality in learning and development. These case examples suggest how a collaborative effort by sport scientists and coaches in children and youth sport may be undertaken in a department of methodology to enrich learning and performance. [ABSTRACT FROM AUTHOR]

This conceptual analysis aims to challenge the state of high-performance sport by questioning the concept of specialization. To start, we offer a brief, but critical overview of what specialization currently entails. Then, shifting the paradigm, we suggest an expansion rather than a reduction of developmental possibilities once an athlete reaches the "top". Specifically, rather than athletes conforming to national standards imposed by governing bodies about what it means to be "elite", we suggest sport systems consider a person-environment fit approach to support ongoing development. Drawing on an ecological dynamics rationale and various socio-cultural theories, we explore how concepts such as affordances and perspectives can be harnessed to create a better "fit" between athletes' action capabilities and the opportunities within their broader environment. Our conception of specialization requires moving away from a definition of success based on the accumulation of medals, toward one that accounts for the exploration and achievement of the possible. We argue that a person-environment fit welcomes diversity, so long as it sustains the person's health, wellbeing, and performance. This, it is suggested, is about collectively holding open spaces for each other to explore beyond the constraints of high-performance sport, encouraging all to carry on their lives in directions meaningfully impactful for them. We conclude this conceptual analysis with a brief case example demonstrating what our theorizing could look like in practice. [ABSTRACT FROM AUTHOR]

Ideas and concepts taken from ecological dynamics might provide an alternative perspective on physical literacy assessment. The aim of this paper was to pilot an assessment of physical literacy conceptualised in an ecological dynamics theoretical rationale. The assessment that was designed has a number of unique features: its scale of analysis is captured at an individual-environment interaction level during game play and it captures key affordances that a child is attuning to and how they are functionally playing the game. Data collection involved observing primary school children playing invasion games in physical education classes. Digital, video-based tagging (Dartfish Pro) of children's behaviours using the emergent game-based assessment tool was completed. Pilot data provided insights on the potential rich interpretations possible, such as readily differentiating between low and high physical literacy learners’ behaviours when playing small-sided games. Greater knowledge of the performance environment was observed in children with higher physical literacy, noted through a greater capacity to favourably regulate their relative positioning between competing and cooperating players, adopting more varied offensive functionality, and exhibiting greater attunement to key affordances. Better understanding children's knowledge of the environment during games play, provides practitioners novel insight into how physical literacy reveals itself through embedded actions. This appreciation can help inform practice more holistically, contributing to richer learning environments and task design.

Sport science has increasingly witnessed use of contemporary ecological approaches to athlete development, preparation, and skill acquisition, providing alternatives to traditional pedagogical approaches. Here we examine an ecological perspective on transferring theory into coaching practice for athlete self-regulation and performance preparation, by presenting the case example of one lead coach and three athletes representing Team GB in the sport of Canoe Slalom at the 2020 Olympics in Tokyo. The aims of this case exemplar are: (1) to offer insights into how an ecological dynamics rationale supported integration of nonlinear pedagogy and (skill) training periodisation, underpinning athlete preparation for world class Canoe Slalom competition; and (2), to provide a first-hand perspective on transfer of theory to support self-regulation, skill learning, and performance preparation in high-performance sport. In the case example, the ‘Periodisation of Skill Training’ framework (i.e., termed ‘PoST’ framework) for venue specific preparation at the Tokyo Olympics was applied and adapted. Principles of co-design, the Constraints-Led Approach, perception-action coupling and representative learning design were embedded within collaborative application of the framework across a support team including athlete, coach and psychologist. To conclude, facilitating athlete self-regulation is highlighted in practical exemplars to support paddlers to cope with the dynamic environments in canoe slalom.

For practitioners working in high performance sport, the primary goal is to ensure that precious preparation time is utilised efficiently, effectively and resourcefully to provide maximal impact on the performance potential of the individual or team. To achieve this goal, there is a need to treat athlete learning and development as an integral part of performing with a key focus on increasingly aligning the relation between the perfomer(s) and their environment, which may differ according to practice and performance (Button et al., 2020b). This article critiqued the weaknesses and limitations of traditional learning approaches in sport, seeking to highlight instead the value of adopting a contemporary ecological dynamics perspective, informing how practitioners should design practice to support a greater connectivity between the contexts of performance and learning.

Self-regulation of learning (SRL) in sports has received much attention from sport sciences researchers. Zimmerman's theory of SRL is frequently used in sport psychology, which, in turn, is derived from the social cognitive theory of self-regulation developed by Bandura. Despite all the contributions to the domain of expertise in general, and sport in particular, this approach has limitations for the understanding and evaluation of SRL in sport performance. Alternatively, we discuss an ecological dynamics perspective of SRL, emphasizing the transactional relationship established between performers and environment as an alternative to attribute to metacognition the explanation for goal directed behaviour, as they self-regulate their performance behaviours. We also discuss methodological consequences for capturing SRL in sport performance guided by an ecological dynamics framework.

In this article we aim to define and present the complementary nature of talent, skill and expertise. Human daily life is replete with expressions of skillful behaviours while interacting with the world, which in specific socio-culturally defined domains, such as sport and work, demand a specialization of such ubiquitous skill. Certain manifestations of ubiquitous skill are identified by experts from the specialized domain of sport with the label of “talent”. In this paper we propose that “talent” is thus socially defined, considered identifiable at an early age and forms the basis for selection and entry at the starting point in domains like sport. Once an individual, defined as “talented” enters the “pathway” for participating in the sport domain, there begins an intense socialization process where training, evaluation, institutionalization and framing takes place for continued development of such talent. This is the formalised process of working on ubiquitous skills refining and changing them into specialized skills in sport. An ecological dynamics rationale is used to explain that this specialization approach is developed through a process of expert skill learning, which entails the stages of exploration and education of intention stabilization and perceptual attunement, and exploitation and calibration. Skill learning aims to develop potentiality and its expression in actuality, i.e., how learning is expressed in contextualized expert performance.

There has been an increase interest in knowing and enacting pedagogical approaches such as the Constraints-led Approach (CLA) and Nonlinear Pedagogy (NLP) which are underpinned by Ecological Dynamics in recent years among practitioners. While there seems to be a perceived uptake of such pedagogical approaches that encourages exploratory learning and the development of individualised movement solutions, there are still concerns on how these pedagogical approaches are enacted on the ground. In this paper, we the authors, as “pracademics”, attempted to address some of the common concerns that we are aware of from our regular interactions with academics and practitioners. In brief, we highlighted some of the common challenges related to sense making concepts from Ecological Dynamics and building connections to practice. We stressed the need to invest time to think differently to create representative learning environment, rethink how assessment is to be done, finding a balance between theoretical jargon and practical application as well as intentionally situating coach development and support. We may not have all the answers, but we hope this paper could provide a useful starting point on how to apply Ecological Dynamics Theory to practice design.

The use of the term problem-solving in relation to movement behavior is an often-broached topic within kinesiology. Here we present a clear rationale for the concept of problem-solving, specifically pertaining to the skilled organization of movement behaviors in sport performance, and the respective processes that underpin it, conceptualized within an ecological dynamics framework. The movement behavior that emerges in sport can be viewed as a problem-solving activity for the athlete, where integrated movement solutions are underpinned by intertwined processes of perception, cognition, and action. This movement problem-solving process becomes functionally aligned with sport performance challenges through a tight coupling to relevant information sources in the environment, which specify affordances offered to the athlete. This ecological perspective can shape our lens on how movements are coordinated and controlled in the context of sport, influencing practical approaches utilized towards facilitating dexterity of athletes. These ideas imply how coaches could set alive movement problems for athletes to solve within practice environments, where they would be required to continuously (re)organize movement system degrees of freedom in relation to dynamic and emergent opportunities, across diverse, complex problems. Through these experiences, athletes could become attuned, intentional, and adaptable, capable of (re)organizing a behavioral fit to performance problems in context—essentially allowing them to become one with the movement problem.

Introduction: The assessment of children’s motor competence is an important concern as physical inactivity has been linked with poor movement quality and aspects of well-being such as low self-esteem. The General Movement Competence Assessment (GMCA) is a new instrument that was developed using active video gaming technology.Methods: Confirmatory factor analysis was conducted to examine the internal validity of the GMCA in a sample of 253 typically developing children (135 boys and 118 girls), aged 7–12 years old (9.9 ± 1.6 years). Further, a second-order confirmatory factor analysis examined how the four constructs fit onto the higher-order variable of movement competence.Results: Results revealed that the first-order four-construct model of the GMCA was a good fit (CFI 0.98; TLI 0.98; RMSEA 0.05). The second-order confirmatory factor analysis revealed that the four constructs loaded directly onto movement competence. It accounted for 95.44% of the variance which is approximately 20% more than the first-order model. The internal structure of the GMCA identified four constructs of movement competence (i.e., stability, object-control, locomotion and dexterity) based on the study sample.Discussion: Performance trends in the general movement competence assessment support empirical evidence that movement competence improves as children age. Results suggest that active video games have considerable potential to help assess general motor competency in the wider population. Future work may consider the sensitivity of motion-sensing technologies in detecting developmental changes over time.

Ecological dynamics is driven by complex ecological networks. Computational capabilities of artificial networks have been exploited for machine learning purposes, yet whether an ecological network possesses a computational capability and whether/how we can use it remain unclear. Here, we developed two new computational/empirical frameworks based on reservoir computing and show that ecological dynamics can be used as a computational resource. In silico ecological reservoir computing (ERC) reconstructs ecological dynamics from empirical time series and uses simulated system responses for information processing, which can predict near future of chaotic dynamics and emulate nonlinear dynamics. The real-time ERC uses real population dynamics of a unicellular organism, Tetrahymena thermophila. The temperature of the medium is an input signal and population dynamics is used as a computational resource. Intriguingly, the real-time ecological reservoir has necessary conditions for computing (e.g. synchronized dynamics in response to the same input sequences) and can make near-future predictions of empirical time series, showing the first empirical evidence that population-level phenomenon is capable of real-time computations. Our finding that ecological dynamics possess computational capability poses new research questions for computational science and ecology: how can we efficiently use it and how is it actually used, evolved and maintained in an ecosystem?

This conceptual analysis aims to challenge the state of high-performance sport by questioning the concept of specialization. To start, we offer a brief, but critical overview of what specialization currently entails. Then, shifting the paradigm, we suggest an expansion rather than a reduction of developmental possibilities once an athlete reaches the “top”. Specifically, rather than athletes conforming to national standards imposed by governing bodies about what it means to be “elite”, we suggest sport systems consider a person-environment fit approach to support ongoing development. Drawing on an ecological dynamics rationale and various socio-cultural theories, we explore how concepts such as affordances and perspectives can be harnessed to create a better “fit” between athletes’ action capabilities and the opportunities within their broader environment. Our conception of specialization requires moving away from a definition of success based on the accumulation of medals, toward one that accounts for the exploration and achievement of the possible. We argue that a person-environment fit welcomes diversity, so long as it sustains the person’s health, wellbeing, and performance. This, it is suggested, is about collectively holding open spaces for each other to explore beyond the constraints of high-performance sport, encouraging all to carry on their lives in directions meaningfully impactful for them. We conclude this conceptual analysis with a brief case example demonstrating what our theorizing could look like in practice.

The aim of the present study was to investigate if the presence of anterior cruciate ligament (ACL) injury risk factors depicted in the laboratory would reflect at-risk patterns in football-specific field data. Twenty-four female footballers (14.9 ± 0.9 year) performed unanticipated cutting maneuvers in a laboratory setting and on the football pitch during football-specific exercises (F-EX) and games (F-GAME). Knee joint moments were collected in the laboratory and grouped using hierarchical agglomerative clustering. The clusters were used to investigate the kinematics collected on field through wearable sensors. Three clusters emerged: Cluster 1 presented the lowest knee moments; Cluster 2 presented high knee extension but low knee abduction and rotation moments; Cluster 3 presented the highest knee abduction, extension, and external rotation moments. In F-EX, greater knee abduction angles were found in Cluster 2 and 3 compared to Cluster 1 (p = 0.007). Cluster 2 showed the lowest knee and hip flexion angles (p < 0.013). Cluster 3 showed the greatest hip external rotation angles (p = 0.006). In F-GAME, Cluster 3 presented the greatest knee external rotation and lowest knee flexion angles (p = 0.003). Clinically relevant differences towards ACL injury identified in the laboratory reflected at-risk patterns only in part when cutting on the field: in the field, low-risk players exhibited similar kinematic patterns as the high-risk players. Therefore, in-lab injury risk screening may lack ecological validity. [ABSTRACT FROM AUTHOR]

Rietveld discusses three skills that artistic practices have to offer to makers of technologies for embedding such technologies in society. An ecological dynamics model of skill learning empowers the embedding of Rietveld's described skills in three social domains: technology makers, artworkers, and visitors of such artworks. [ABSTRACT FROM AUTHOR]

Diving saves are the main duty of football goalkeepers. Few biomechanical investigations of dive techniques have been conducted, none in a sport-specific environment. The present study investigated the characteristics of goalkeepers' dive in preferred (PS) and non-preferred (nPS) side through an innovative wearables-plus-principal-component analysis (PCA) approach. Nineteen competitive academy goalkeepers (16.5 ± 3.0 years) performed a series of high and low dives on their PS and nPS. Dives were performed in a regular football goal on the pitch. Full-body kinematics were collected through 17 wearable inertial sensors (MTw Awinda, Xsens). PCA was conducted to reduce data dimensionality (input matrix 310,878 datapoints). PCA scores were extracted for each kinematic variable and compared between PS and nPS if their explained variability was >5%. In high dive, participants exhibited greater hip internal rotation and less trunk lateral tilt (p < 0.047, ES > 0.39) in PS than nPS. In low dives, players exhibited greater ipsilateral hip abduction dominance and lower trunk rotation (p < 0.037, ES > 0.40) in PS than nPS. When diving on their nPS, goalkeepers adopted sub-optimal patterns with less trunk coordination and limited explosiveness. An ecological testing through wearables and PCA might help coaches to inspect relevant diving characteristics and improve training effectiveness. [ABSTRACT FROM AUTHOR]

Drowning has been the cause of over 2.5 million preventable deaths in the past decade. Despite the fact that the majority of drownings occur in open water, assessment of water safety competency typically occurs in swimming pools. The assessment of water safety competency in open water environments brings with it a few difficulties, but also promises tremendous benefits. The aim of this position paper is to discuss the benefits and caveats of conducting assessments in open water environments as opposed to closed and controlled environments, and to provide recommendations for evidence based practice. The first theoretical section discusses the effects of the environment and key variables (such as temperature and water movement) on various factors of assessment. These discussions are linked to the two perspectives of representative learning design (based on ecological dynamics) and information processing theory. The second section presents two pilot studies of relevance and provides practical implications for assessment of water safety competency. It seems that a combination of pool-based practice and open water education may be ideal in assessing aquatic skills competency. Assessment in open water presents clear benefits regarding validity, but often poses seemingly unsurmountable barriers, which providers may have reservations about in the absence of clear evidence. Hence this article provides a robust discussion about competency assessment and signals the practical importance of faithfully reproducing the environment in which skilled behavior is most relevant. [ABSTRACT FROM AUTHOR]

1. Ecologists have long recognized that the losses and gains in local species abundances can either decrease or increase spatial beta diversity, phenomena often referred to as biotic homogenization and differentiation, respectively. However, quantifying such dynamic impacts of species abundances on beta diversity has remained a methodological challenge. 2. Here, we develop a numerical method to additively partition the temporal changes in beta diversity into distinct components that reflect the losses and gains in local species abundances. Our method is based on Ružička and Bray-Curtis indices and the normalized abundance-based Whittaker's beta diversity. The temporal changes in these measures are partitioned into components that represent biotic homogenization and differentiation driven by abundance losses and gains at both species and community levels. 3. Application of the method to a Swedish fish community dataset revealed decreases in beta diversity between 1990 and 2018. The homogenization of fish communities was explained by gains, but not losses, in species abundances across sites. Species-level partitioning further showed that the homogenization was largely caused by the increased population sizes of a particular species in sites where it was already present. 4. The results highlight that our partitioning method effectively identifies local population and community processes embedded in regional biodiversity patterns. We believe that explicit analyses of the losses and gains in species abundances should bring deeper insights into the dynamics of beta diversity. [ABSTRACT FROM AUTHOR]

Abstract Changing environmental conditions can infer structural modifications of predator‐prey communities. New conditions often increase mortality which reduces population sizes. Following this, predation pressure may decrease until populations are dense again. Dilution may thus have substantial impact not only on ecological but also on evolutionary dynamics because it amends population densities. Experimental studies, in which microbial populations are maintained by a repeated dilution into fresh conditions after a certain period, are extensively used approaches allowing us to obtain mechanistic insights into fundamental processes. By design, dilution, which depends on transfer volume (modifying mortality) and transfer interval (determining the time of interaction), is an inherent feature of these experiments, but often receives little attention. We further explore previously published data from a live predator‐prey (bacteria and ciliates) system which investigated eco‐evolutionary principles and apply a mathematical model to predict how various transfer volumes and transfer intervals would affect such an experiment. We find not only the ecological dynamics to be modified by both factors but also the evolutionary rates to be affected. Our work predicts that the evolution of the anti‐predator defense in the bacteria, and the evolution of the predation efficiency in the ciliates, both slow down with lower transfer volume, but speed up with longer transfer intervals. Our results provide testable hypotheses for future studies of predator‐prey systems, and we hope this work will help improve our understanding of how ecological and evolutionary processes together shape composition of microbial communities.

A computational revolution unleashed the power of artificial neural networks. At the heart of that revolution is automatic differentiation, which calculates the derivative of a performance measure relative to a large number of parameters. Differentiation enhances the discovery of improved performance in large models, an achievement that was previously difficult or impossible. Recently, a second computational advance optimizes the temporal trajectories traced by differential equations. Optimization requires differentiating a measure of performance over a trajectory, such as the closeness of tracking the environment, with respect to the parameters of the differential equations. Because model trajectories are usually calculated numerically by multistep algorithms, such as Runge-Kutta, the automatic differentiation must be passed through the numerical algorithm. This article explains how such automatic differentiation of trajectories is achieved. It also discusses why such computational breakthroughs are likely to advance theoretical and statistical studies of biological problems, in which one can consider variables as dynamic paths over time and space. Many common problems arise between improving success in computational learning models over performance landscapes, improving evolutionary fitness over adaptive landscapes, and improving statistical fits to data over information landscapes.

Considerable studies have been conducted to quantify and examine free cyanophage particles across a wide range of aquatic systems, but few studies have analyzed the dynamics of host cell fraction cyanophages, and even less is known about tropical freshwater cyanophages. Here, we employed qPCR to examine the abundances of four ecologically relevant novel cyanophages (PA-SR01, S-SRP01, S-SRP02 and S-SRM01) in a tropical urban lake in Singapore from July to November 2019. Besides quantifying the extracellular free cyanophage particles, host cell fraction cyanophage were also examined to represent the abundance of intracellular and attached phages. Our study revealed differing fate and dynamics of each cyanophage target. Host cell fraction phage abundance was found to be more abundant than free phage abundance, indicating high level of infection and rapid dispersal of phage particles upon lysis. By further investigating the correlations between free phage particle abundance and numerous biotic (total cyanobacteria, Microcystis abundances, etc) as well as abiotic (nutrients and physiochemical water quality) variables, multiple correlations across different sampling sites were obtained, suggesting pH and rainfall to be potential key factors driving shifts in both cyanophage and cyanobacteria population. This study demonstrated the ecological importance and key roles of the cyanophage PA-SR01, S-SRP01, S-SRP02 and S-SRM01 in tropical freshwater lakes not only as regulators of the cyanobacterial community, but also as promoters of certain cyanotoxin production.

Drowning has been the cause of over 2.5 million preventable deaths in the past decade. Despite the fact that the majority of drownings occur in open water, assessment of water safety competency typically occurs in swimming pools. The assessment of water safety competency in open water environments brings with it a few difficulties, but also promises tremendous benefits. The aim of this position paper is to discuss the benefits and caveats of conducting assessments in open water environments as opposed to closed and controlled environments, and to provide recommendations for evidence-based practice. The first theoretical section discusses the effects of the environment and key variables (such as temperature and water movement) on various factors of assessment. These discussions are linked to the two perspectives of representative learning design (based on ecological dynamics) and information processing theory. The second section presents two pilot studies of relevance and provides practical implications for assessment of water safety competency. It seems that a combination of pool-based practice and open water education may be ideal in assessing aquatic skills competency. Assessment in open water presents clear benefits regarding validity, but often poses seemingly unsurmountable barriers, which providers may have reservations about in the absence of clear evidence. Hence this article provides a robust discussion about competency assessment and signals the practical importance of faithfully reproducing the environment in which skilled behavior is most relevant.

Evidence investigating skilled performers in sport suggests that a prominent component of skilled behavior is, in part, due to the development of more effective and efficient perception-action couplings. Further, the Quiet Eye has emerged as a useful tool in which to investigate how skilled performers regulate action through fixating on visual information within the immediate environment before the onset of a goal directed movement. However, only a few contributions to the literature have attempted to examine the individual variations within these Quiet Eye fixations in skilled participants. In this case study, we first asked how goalkeepers control their actions, via the Quiet Eye in a representative task. Second, we sought to examine whether inter- and intra-individual differences in the Quiet Eye are present in skilled goalkeepers as a functional component of skilled performance. Results were consistent with previous work on football goalkeepers, with QE fixations located at the ball and visual pivot. However, individual analysis reveals different Quiet Eye gaze patterning between (inter) and within (intra) the goalkeepers during saving actions. To conclude, we have provided a descriptive case study in attempt to understand the Quiet Eye behaviors of a skilled sample of professional goalkeepers. In doing so we have suggested how adaptive variability, founded upon an Ecological Dynamics framework, may provide further insight into the function of the Quiet Eye. [ABSTRACT FROM AUTHOR]

The alpine treeline ecotones are an early indicator of vegetation's response to changes in climate, and the advancement of diffuse treeline ecotones has been associated with mean annual warming temperatures. However, the knowledge of how tree demographic size, age and population distribution, and regeneration decrease with increasing elevation and mean annual temperature remain fragmentary in Bhutan. There was no explanation of how treelines migrate in response to the climate. Therefore, the objectives of this study were to investigate tree demographic size and age and population distribution, as well as the regeneration expansion of treeline ecotones of Abies densa trees in response to climate change. Demographic data from thirty transect bands from treeline ecotones and reconstructed mean annual temperatures from tree-rings were used. Regression analysis was used to establish a relationship between elevation/temperature and demographic tree size and age, as well as to determine recruitment frequency distributions and whether these could be driven by climate change. The tree demography indicated that the treeline ecotone in our sampling site is temperature limited. Hence, cooler temperatures at higher elevations should drive decreases in basal diameter, age and recruitment frequencies. From the dendroecological analysis, the diffuse treeline ecotones appear to be climbing on average 1.00 m per year in Northern Bhutan. We also found that the recruitment frequency has increased over recent years (1850–2017), as temperatures continue to rise. The thermal treeline ecotones will be likely to serve as a line of bioclimatic reference against which other zones of bioclimate can be defined. With documented responses of treeline ecotones toward mean annual temperatures, the expectation is that additional warming will continue to influence regeneration expansion in the future. This dynamic response of treeline ecotones towards the climate acts as an indicator of climate change. Information about climbing treelines and altered ecotones should be a vital part of the material for decision makers to consider, to assess impacts and threats to Himalayan alpine biota. [ABSTRACT FROM AUTHOR]