Consistent scaling of population structure across landscapes despite intraspecific variation in movement and connectivity

Understanding the spatial scale of population structure is fundamental to long-standing tenets of population biology, landscape ecology and conservation. Nonetheless, identifying such scales has been challenging because a key factor that influences scaling – movement among patches or local populations – is a multicausal process with substantial phenotypic and temporal variation.
We resolve this problem via a novel application of network modularity. When applied to movements, modularity provides a formal description of the functional aggregation of populations and identifies potentially critical scales for ecological and evolutionary dynamics. We first test for modularity using several different types of biologically relevant movements across the entire geographic range of an endangered bird, the snail kite (Rostrhamus sociabilis plumbeus). We then ask whether variation in movement based on (i) age, (ii) sex and (iii) time (annual, seasonal and within-season movements) influences spatia...

理解种群结构的空间尺度是种群生物学、景观生态学及保护领域长期基本原则的核心。然而，识别此类尺度颇具挑战，因为影响尺度的关键因素——斑块或局部种群间的迁移——是一个具有显著表型和时间变异的多因过程。

我们通过网络模块化（network modularity）的新颖应用解决了这一问题。将模块化应用于迁移时，它可为种群的功能聚合提供正式描述，并识别生态与进化动态的潜在关键尺度。我们首先利用濒危鸟类蜗牛鸢（Rostrhamus sociabilis plumbeus）整个地理分布范围内的多种不同类型生物学相关迁移，对模块化进行了测试。随后我们探究，基于（i）年龄、（ii）性别及（iii）时间（年度、季节及季节内迁移）的迁移变异是否会影响空间...