Spatial Scaling with an Unusual Food Web Structure: The Case of Azteca Ants in the Coffee Agroecosytem

自然并不是以统一的方式排列的。无论你往哪里看，从局部的疾病暴发，到森林中的植物物种，再到潮汐岩石上的藤壶，斑块都是显而易见的。多年来，物种和生态系统的这种空间聚集一直吸引着生态学家的兴趣，有许多技术可以描述现有的格局。然而，这些图案是如何形成的，是什么首先创造了这些斑块，这往往是一个谜。在这项研究中，一种常见的蚂蚁物种出现在新大陆热带地区，被认为是几种作物的潜在害虫物种，已知出现在相对较大的斑块中。众所周知，它还可以保护介壳虫免受无处不在的寄生蜂的侵袭，但经常受到一种寄生苍蝇的攻击。因此，当地的动态包括两个“捕食者-猎物”系统(黄蜂与介壳虫和寄生蝇与蚂蚁)以及一个关键的互惠关系(蚂蚁保护介壳虫)。利用生态学理论的最新进展，这些局部细节将被转化为数学模型，然后将用于探索斑块如何形成的潜在机制，以及它们的最终命运可能是什么。

Nature is not arranged in a uniform way. Patches are evident wherever you look, from localized disease outbreaks, to species of plants in the forest, to barnacles on the tidal rocks. This spatial aggregation of species and ecosystems has intrigued ecologists for many years and many techniques exist for describing the existing patterns. However, it is frequently quite enigmatic how the patterns are formed, what it is that creates the patches in the first place. In this research a common species of ant that occurs throughout the new world tropics, and is regarded as a potential pest species in several crops, is known to occur in relatively large patches. It is also known to protect scale insects from ever-present parasitic wasps, but is frequently attacked by a species of parasitic fly. The local dynamics thus involve two "predator-prey" systems (wasp versus scale insect and parasitic fly versus ant) coupled together with a key mutualism (the ant's protecting the scale insects). Using recent advances in ecological theory, these local details will be translated into a mathematical model that will then be used to explore the underlying mechanisms of how the patches are formed, and what their ultimate fate might be.