Ecosystem functions of tropical ants - comparing primary and secondary rainforest on two continents

目前的灭绝率比史前时期高出100至1000倍。目前热带雨林的生物多样性损失最严重，这些雨林被砍伐和/或被改造成种植园或次生生境。然而，物种灭绝的生态系统效应仍然没有得到充分的理解。特别是，人们在很大程度上不知道一个灭绝物种的生态系统影响是否可以被其他物种所缓冲，或者一个物种的消失是否会导致连锁反应。蚂蚁是热带雨林中最丰富的动物类群之一，因此对生态系统有重大影响。在这个项目中，我们将研究南美洲和东南亚的原生林和次生林中蚂蚁群落的生态系统效应（或“功能”）。在每个地点，我们将评估蚂蚁在一系列与食物消耗和食物资源防御相关的生态系统功能中的表现。我们将使用标准化实验来评估每个栖息地中最丰富的蚂蚁物种的这些功能。研究结果将用于（1）评估生态系统功能和功能冗余的蚂蚁群落在主要和干扰的栖息地，（2）比较生态相似，但地理上遥远的地理区域的蚂蚁群落的生态位分化，和（3）评估专业化和功能性能之间的权衡同宗蚂蚁物种。因此，我们的方法可以直接量化生态系统功能和蚂蚁物种之间的功能分化，并可用于各种研究问题。

The present extinction rates are 100 to 1000 times higher than in prehistoric ages. The current loss in biodiversity is highest in tropical rainforests, which are logged and/or converted to plantations or secondary habitats. However, the ecosystem effects of species extinctions are still insufficiently understood. In particular, it is largely unknown whether the ecosystem effects of an extinct species can be buffered by others, or whether the loss of a species results in a cascade of linked extinctions. Ants are among the most abundant animal taxa in tropical rainforests and therefore have major impacts on the ecosystem. In this project, we will study the ecosystem effects (or ‘functions’) of ant communities in primary and secondary forests in South America and Southeast Asia. At each site, we will assess the ants’ performance in a set of ecosystem functions that are related to food consumption and the defense of food resources. We will use standardized experiments to assess these functions for the most abundant ant species in each habitat. The results will be used (1) to assess ecosystem functioning and functional redundancy of ant communities in primary and disturbed habitats, (2) to compare niche differentiation in ant communities of two ecologically similar, but geographically distant biogeographical regions, and (3) to evaluate trade-offs between specialization and functional performance among syntopic ant species. Our approach thus allows to directly quantify ecosystem functions and functional differentiation among ant species, and can be used for a variety of research questions.