Quantitative analysis is increasingly being used in team sports to better understand performance in these stylized,delineated,complex social systems.Here,the authors provide a first step toward understanding the patte...Quantitative analysis is increasingly being used in team sports to better understand performance in these stylized,delineated,complex social systems.Here,the authors provide a first step toward understanding the pattern-forming dynamics that emerge from collective offensive and defensive behavior in team sports.The authors propose a novel method of analysis that captures how teams occupy sub-areas of the field as the ball changes location.The authors use this method to analyze a game of association football(soccer) based upon a hypothesis that local player numerical dominance is key to defensive stability and offensive opportunity.The authors find that the teams consistently allocated more players than their opponents in sub-areas of play closer to their own goal.This is consistent with a predominantly defensive strategy intended to prevent yielding even a single goal.The authors also find differences between the two teams' strategies:while both adopted the same distribution of defensive,midfield,and attacking players(a 4:3:3 system of play),one team was significantly more effective in maintaining both defensive and offensive numerical dominance for defensive stability and offensive opportunity.That team indeed won the match with an advantage of one goal(2 to 1) but the analysis shows the advantage in play was more pervasive than the single goal victory would indicate.The proposed focus on the local dynamics of team collective behavior is distinct from the traditional focus on individual player capability.It supports a broader view in which specific player abilities contribute within the context of the dynamics of multiplayer team coordination and coaching strategy.By applying this complex system analysis to association football,the authors can understand how players' and teams' strategies result in successful and unsuccessful relationships between teammates and opponents in the area of play.展开更多
Sexual imprinting is a common mechanism of mate preference learning. It is thought to influence how traits evolve and in some cases to promote speciation. Recently there has been increasing interest in how sexual impr...Sexual imprinting is a common mechanism of mate preference learning. It is thought to influence how traits evolve and in some cases to promote speciation. Recently there has been increasing interest in how sexual imprinting itself evolves. Theoretical work on polygynous mating systems predicts that females will evolve paternal imprinting, which means they learn to prefer phenotypes expressed by their fathers. In nature however, females of some species learn to prefer phenotypes expressed by their mothers instead. We used a dynamical systems model and tools from adaptive dynamics to study how sexual imprinting evolves in species with socially monogamous mating systems. We considered cases in which the target trait for imprinting is un- der viability selection but is not a reliable signal of paternal investment. Thus, the target trait signals the genetic benefits rather than the parental care benefits of mate choice. When mating is socially monogamous and there is some extra-pair patemity, we show that maternal imprinting can be favored over paternal imprinting. Counterintuitively, females often become choosier when selecting social partners in systems where extra-pair mating is more frequent. That is, females may be more selective when choosing social partners that will sire a smaller percentage of their offspring. Our results offer new testable hypotheses, and ad- vance our understanding of the mechanisms that drive the evolution of mate choice strategies in nature .展开更多
基金supported by the Portuguese Foundation for Science and Technology(SFRH/BD/43251/2008)
文摘Quantitative analysis is increasingly being used in team sports to better understand performance in these stylized,delineated,complex social systems.Here,the authors provide a first step toward understanding the pattern-forming dynamics that emerge from collective offensive and defensive behavior in team sports.The authors propose a novel method of analysis that captures how teams occupy sub-areas of the field as the ball changes location.The authors use this method to analyze a game of association football(soccer) based upon a hypothesis that local player numerical dominance is key to defensive stability and offensive opportunity.The authors find that the teams consistently allocated more players than their opponents in sub-areas of play closer to their own goal.This is consistent with a predominantly defensive strategy intended to prevent yielding even a single goal.The authors also find differences between the two teams' strategies:while both adopted the same distribution of defensive,midfield,and attacking players(a 4:3:3 system of play),one team was significantly more effective in maintaining both defensive and offensive numerical dominance for defensive stability and offensive opportunity.That team indeed won the match with an advantage of one goal(2 to 1) but the analysis shows the advantage in play was more pervasive than the single goal victory would indicate.The proposed focus on the local dynamics of team collective behavior is distinct from the traditional focus on individual player capability.It supports a broader view in which specific player abilities contribute within the context of the dynamics of multiplayer team coordination and coaching strategy.By applying this complex system analysis to association football,the authors can understand how players' and teams' strategies result in successful and unsuccessful relationships between teammates and opponents in the area of play.
文摘Sexual imprinting is a common mechanism of mate preference learning. It is thought to influence how traits evolve and in some cases to promote speciation. Recently there has been increasing interest in how sexual imprinting itself evolves. Theoretical work on polygynous mating systems predicts that females will evolve paternal imprinting, which means they learn to prefer phenotypes expressed by their fathers. In nature however, females of some species learn to prefer phenotypes expressed by their mothers instead. We used a dynamical systems model and tools from adaptive dynamics to study how sexual imprinting evolves in species with socially monogamous mating systems. We considered cases in which the target trait for imprinting is un- der viability selection but is not a reliable signal of paternal investment. Thus, the target trait signals the genetic benefits rather than the parental care benefits of mate choice. When mating is socially monogamous and there is some extra-pair patemity, we show that maternal imprinting can be favored over paternal imprinting. Counterintuitively, females often become choosier when selecting social partners in systems where extra-pair mating is more frequent. That is, females may be more selective when choosing social partners that will sire a smaller percentage of their offspring. Our results offer new testable hypotheses, and ad- vance our understanding of the mechanisms that drive the evolution of mate choice strategies in nature .
