The influence of biogeographical and evolutionary histories on morphological trait-matching and resource specialization in mutualistic hummingbird-plant networks

Functional traits can determine pairwise species interactions, such as those between plants and pollinators. However, the effects of biogeography and evolutionary history on trait-matching and trait-mediated resource specialization remain poorly understood. We compiled a database of 93 mutualistic hummingbird-plant networks (including 181 hummingbird and 1,256 plant species), complemented by morphological measures of hummingbird bill and floral corolla length. We divided the hummingbirds into their principal clades and used knowledge on hummingbird biogeography to divide the networks into four biogeographical regions: Lowland South America, Andes, North & Central America, and the Caribbean islands. We then tested: (i) whether hummingbird clades and biogeographical regions differ in hummingbird bill length, corolla length of visited flowers and resource specialization, and (ii) whether hummingbirds’ bill length correlates with the corolla length of their food plants and with their...功能性状（functional traits）可决定物种种间的成对互作，例如植物与传粉者之间的互作。然而，生物地理学与演化历史对性状匹配及性状介导的资源特化的影响，目前仍未得到充分阐明。 我们构建了包含93个互利共生蜂鸟-植物互作网络的数据库，涵盖181种蜂鸟与1256种植物，并补充了蜂鸟喙长与花卉花冠长度的形态学测量数据。我们将蜂鸟划分为其主要演化支，并结合蜂鸟生物地理学知识，将所有互作网络划分为4个生物地理区域：低地南美洲、安第斯山脉、北美与中美洲以及加勒比群岛。随后我们开展了两项检验：(i) 蜂鸟演化支与生物地理区域在蜂鸟喙长、访花花冠长度及资源特化程度上是否存在差异；(ii) 蜂鸟喙长是否与其取食植物的花冠长度以及其……