Abstract:
Interactions between species are influenced by different ecological mechanisms, such as morphological matching, phenological overlap and species abundances. How these mechanisms explain interaction frequencies across environmental gradients remains poorly understood. Consequently, we also know little about the mechanisms that drive the geographical patterns in network structure, such as complementary specialization and modularity. Here, we use data on morphologies, phenologies and abundances to explain interaction frequencies between hummingbirds and plants at a large geographical scale. For 24 quantitative networks sampled throughout the Americas, we found that the tendency of species to interact with morphologically matching partners contributed to specialized and modular network structures. Morphological matching best explained interaction frequencies in networks found closer to the equator and in areas with low-temperature seasonality. When comparing the three ecological mechanisms within networks, we found that both morphological matching and phenological overlap generally outperformed abundances in the explanation of interaction frequencies. Together, these findings provide insights into the ecological mechanisms that underlie geographical patterns in resource specialization. Notably, our results highlight morphological constraints on interactions as a potential explanation for increasing resource specialization towards lower latitudes.
摘要:
物种之间的相互作用受到不同生态机制的影响,比如形态学匹配,物候重叠和物种丰度。这些机制如何解释跨环境梯度的相互作用频率仍然知之甚少。因此,我们对网络结构中驱动地理模式的机制也知之甚少,例如互补的专业化和模块化。这里,我们使用形态数据,物候和丰度可以解释蜂鸟与植物之间在大地理范围内的相互作用频率。对于整个美洲采样的24个定量网络,我们发现,物种与形态匹配伙伴相互作用的趋势促成了专业化和模块化的网络结构。形态匹配最好地解释了网络中靠近赤道和低温季节性地区的相互作用频率。当比较网络内的三种生态机制时,我们发现,在解释相互作用频率方面,形态匹配和物候重叠通常优于丰度。一起,这些发现提供了对资源专业化地理模式基础的生态机制的见解。值得注意的是,我们的结果强调了相互作用的形态约束,作为向低纬度地区增加资源专业化的潜在解释。