Negative density-regulated contest performance promotes conflict resolution in a tree lizard

This project includes the raw data of the research article 'Negative density-regulated contest performance promotes conflict resolution in a tree lizard' by Hsu et al. Data are in the file <code>negative-density-regulated-contest-performance.ods</code> (a OpenDocument spreadsheet). Download and open it by using spreadsheet software (e.g. Microsoft Office Excel, Libreoffice Calc) Sheet <code>covariates by population</code> Column Description Site Lizard population log.female.over.male.ratio Natural logarithm of sex ratio (famel over male) n.injured Number of injured males n.not.injured Number of not injured males injury.ave Injury ratio selectDiff Standardized selection differential of male snout-vent length Comp.1 1st principle component of habitat composition Comp.2 2nd principle component of habitat composition Comp.3 3rd principle component of habitat composition Comp.4 4th principle component of habitat composition invSimpsonTrapAbundance Food items (inverse Simpson index) in item abundance from pitfall trap invSimpsonTrapWeight Food items (inverse Simpson index) in item dry mass from pitfall trap totalTrapWeight Total dry mass of food in pitfall trap (g) invSimpsonStomachAbundance Dietary breadth (inverse Simpson index) in abundance from stomach items invSimpsonStomachWeight Dietary breadth (inverse Simpson index) in dry mass from stomach items totalStomachWeight Total dry mass of items in stomach (g) Sheet <code>covariates by population and sex</code> Column Description Site Lizard population Sex Sex density Number of lizard in 1250 m^2 Sheet <code>stage fight</code> Column Description Site Lizard population resident (SVL) Snout-vent length of resident lizard intruder (SVL) Snout-vent length of intruder lizard max.aggresive Resident highest agressive behavior is.R.win Resident as winner rScore Rank level of resident highest agressive behavior Sheet <code>bite force</code> Column Description Site Lizard population Sex Sex Body weight Lizard body weight (g) Head length Lizard head length (mm) Head width Lizard head width (mm) Head height Lizard head height (mm) SVL Lizard snout-vent length (mm) Bite Force Lizard bite force (N) Abstract Territoriality is a behavioral adaptation resulting from intraspecific competition and reflects the strategy of how individuals share limited resources in the environment. As a consequence, territorial contests and levels of aggressiveness are strongly influenced by population density. The positive relationship between population density and the intensity of intraspecific competition may appear straightforward. However, empirical evidence regarding this association remains inconclusive. This ambiguity may be attributed to studies that have predominantly focused on specific fight-associated traits while overlooking the comprehensive assessment of multiple phenotypic characteristics. To examine the effects of population density and other ecological factors on the variation in fight behavior as well as fight-associated morphology and performance. We conducted population surveys and behavioral experiments using the Swinhoe’s tree lizard across eight populations. Our findings revealed that males from higher-density populations tended to engage in less intense fights and exhibited a weaker resident advantage in fights, which coincided with our findings on lower rates of injuries, weaker bite forces, and smaller body sizes (and vice versa). Male-specific plasticity in fight behavior, morphology, and performance along a density gradient suggests different evolutionary equilibria in territoriality influenced by local costs and benefits. Our study supports the significant role of negative density dependence as a fundamental regulator of eco-evolutionary dynamics. The observed phenotypic plasticity emphasizes the importance of ecological and social factors in shaping ontogenetic growth and life-history strategies. Our findings provide a basis for future investigations into pace-of-life syndromes and shed light on how phenotypic adaptation may shape population structure.本项目包含Hsu等人发表的研究论文《负密度调控的竞赛表现促进树蜥冲突解决》（Negative density-regulated contest performance promotes conflict resolution in a tree lizard）的原始数据。数据存储于文件<code>negative-density-regulated-contest-performance.ods</code>（开放文档电子表格，OpenDocument spreadsheet）中，可使用电子表格软件（如Microsoft Office Excel、LibreOffice Calc）下载并打开该文件。 ### 工作表<code>covariates by population</code>（种群协变量表） 列名与说明： - Site（采样点）：采样位点 - Lizard population（树蜥种群）：树蜥种群 - log.female.over.male.ratio（雌雄性比自然对数）：雌性与雄性数量比的自然对数 - n.injured（受伤雄性个体数）：受伤雄性个体的总数量 - n.not.injured（未受伤雄性个体数）：未受伤雄性个体的总数量 - injury.ave（受伤率）：受伤个体占比 - selectDiff（雄性肛吻长标准化选择差）：雄性肛吻长（snout-vent length, SVL）的标准化选择差 - Comp.1（生境组成第一主成分）：生境组成的第一主成分 - Comp.2（生境组成第二主成分）：生境组成的第二主成分 - Comp.3（生境组成第三主成分）：生境组成的第三主成分 - Comp.4（生境组成第四主成分）：生境组成的第四主成分 - invSimpsonTrapAbundance（陷阱捕获食物丰度逆辛普森指数，inverse Simpson index）：诱捕陷阱获取的食物个体丰度的逆辛普森指数 - invSimpsonTrapWeight（陷阱捕获食物干重逆辛普森指数，inverse Simpson index）：诱捕陷阱获取的食物干重的逆辛普森指数 - totalTrapWeight（陷阱总食物干重）：诱捕陷阱内食物的总干重（单位：克） - invSimpsonStomachAbundance（胃容物丰度逆辛普森指数，inverse Simpson index）：胃容物个体丰度的逆辛普森指数，即食性宽度 - invSimpsonStomachWeight（胃容物干重逆辛普森指数，inverse Simpson index）：胃容物干重的逆辛普森指数，即食性宽度 - totalStomachWeight（胃容物总干重）：胃内食物的总干重（单位：克） ### 工作表<code>covariates by population and sex</code>（种群与性别协变量表） 列名与说明： - Site（采样点）：采样位点 - Lizard population（树蜥种群）：树蜥种群 - Sex（性别）：个体性别 - density（种群密度）：1250平方米范围内的蜥蜴个体总数 ### 工作表<code>stage fight</code>（打斗阶段数据表） 列名与说明： - Site（采样点）：采样位点 - Lizard population（树蜥种群）：树蜥种群 - resident (SVL)（居留者肛吻长）：居留蜥蜴的肛吻长（snout-vent length, SVL） - intruder (SVL)（入侵者肛吻长）：入侵蜥蜴的肛吻长（snout-vent length, SVL） - max.aggresive（最高攻击行为等级）：居留者的最高攻击行为水平 - is.R.win（居留者获胜标记）：标识居留者是否为打斗获胜方 - rScore（最高攻击行为排序等级）：居留者最高攻击行为的排序等级 ### 工作表<code>bite force</code>（咬合力数据表） 列名与说明： - Site（采样点）：采样位点 - Lizard population（树蜥种群）：树蜥种群 - Sex（性别）：个体性别 - Body weight（体重）：蜥蜴体重（单位：克） - Head length（头长）：蜥蜴头长（单位：毫米） - Head width（头宽）：蜥蜴头宽（单位：毫米） - Head height（头高）：蜥蜴头高（单位：毫米） - SVL（肛吻长，snout-vent length）：蜥蜴肛吻长（单位：毫米） - Bite Force（咬合力）：蜥蜴咬合力（单位：牛顿） 领域性是种内竞争催生的行为适应策略，反映了个体在环境中共享有限资源的行为模式。据此，领域竞争与攻击强度受种群密度的影响极为显著。种群密度与种内竞争强度之间的正相关关系看似直观，但该关联的实证证据仍未形成定论。这种认知模糊性可能源于过往研究多聚焦于特定打斗相关性状，却忽视了对多表型特征的全面评估。 为探究种群密度及其他生态因子对打斗行为、打斗相关形态与性能变异的影响，本研究以8个种群的斯文豪氏树蜥（Swinhoe’s tree lizard）为研究对象，开展了种群调查与行为实验。结果显示，高密度种群的雄性个体打斗强度更低，且在打斗中表现出更弱的居留者优势，这与我们观测到的更低受伤率、更弱咬合力以及更小体型的结果一致（反之亦然）。雄性在打斗行为、形态与性能上沿密度梯度的特异性表型可塑性，表明领域性受局部成本与收益影响，存在不同的进化稳定平衡。本研究证实了负密度依赖作为生态进化动力学基本调控因子的重要作用。本次观测到的表型可塑性凸显了生态与社会因子在塑造个体发育生长与生活史策略中的关键意义。本研究结果为未来的生活节奏综合征（pace-of-life syndromes）相关研究提供了基础，并阐明了表型适应如何塑造种群结构。