What can interaction webs tell us about species roles?

The group model is a useful tool to understand broad-scale patterns of interaction in a network, but it has previously been limited in use to food webs, which contain only predator-prey interactions. Natural populations interact with each other in a variety of ways and, although most published ecological networks only include information about a single interaction type (e.g., feeding, pollination), ecologists are beginning to consider networks which combine multiple interaction types. Here we extend the group model to signed directed networks such as ecological interaction webs. As a specific application of this method, we examine the effects of including or excluding specific interaction types on our understanding of species roles in ecological networks. We consider all three currently available interaction webs, two of which are extended plant-mutualist networks with herbivores and parasitoids added, and one of which is an extended intertidal food web with interactions of all possible...

群体模型（group model）是理解网络中大规模相互作用模式的有效工具，但此前其应用仅限于仅包含捕食者-猎物相互作用（predator-prey interactions）的食物网（food webs）。自然种群间存在多种相互作用方式，尽管大多数已发表的生态网络（ecological networks）仅包含单一相互作用类型的信息（如摄食、传粉），但生态学家正开始考虑整合多种相互作用类型的网络。本文将群体模型扩展至带符号有向网络（signed directed networks），例如生态相互作用网（ecological interaction webs）。作为该方法的具体应用，我们探究了纳入或排除特定相互作用类型对理解生态网络中物种角色（species roles）的影响。我们考虑了目前所有可用的三个相互作用网，其中两个是添加了食草动物（herbivores）和寄生蜂（parasitoids）的扩展植物-互利共生网络（plant-mutualist networks），另一个是包含所有可能...的扩展潮间带食物网。