Effects of hummingbird morphology on specialization in pollination networks vary with resource availability

Specialization of species in interaction networks influences network stability and ecosystem functioning. Spatial and temporal variation in resource availability may provide insight into how ecological factors, such as resource abundance, and evolutionary factors, such as phylogenetically conserved morphological traits, influence specialization within mutualistic networks. We used independent measures of hummingbird abundance and resources (nectar), information on hummingbird traits and plant–hummingbird interactions to examine how resource availability and species' morphology influence the specialization of hummingbirds in three habitat types (forest, shrubs, cattle ranch) sampled over 10 sessions across two years in the southern Andes of Ecuador. Specialization of hummingbird species in the networks was measured by three indices: d' (related to niche partitioning), generality (related to niche width) and PSI (related to pollination services). Specialization indices d', generality and ...物种在相互作用网络中的特化程度会对网络稳定性与生态系统功能产生影响。资源可获得性的时空变异，可为揭示生态因子（如资源丰度）与演化因子（如系统发育保守的形态性状）如何影响互利共生网络（mutualistic networks）内的物种特化提供思路。本研究借助蜂鸟丰度与资源（花蜜）的独立测定数据、蜂鸟性状信息以及植物-蜂鸟相互作用数据，探究了资源可获得性与物种形态如何影响厄瓜多尔安第斯山脉南部三种生境（森林、灌丛、牧场）内蜂鸟的特化程度；该研究在两年间开展了10次采样。本研究采用三类指标量化网络内蜂鸟物种的特化程度：d'（关联生态位分化）、泛化度（generality，关联生态位宽度）以及PSI（关联传粉服务）。特化指标d'、泛化度以及……