Department of Ecology and Evolution, The University of Chicago, Chicago, IL 60637;
Department of Ecology and Evolution, The University of Chicago, Chicago, IL 60637.
Proc Natl Acad Sci U S A. 2021 Dec 7;118(49). doi: 10.1073/pnas.2109896118.
Across the tree of life, organisms modify their local environment, rendering it more or less hospitable for other species. Despite the ubiquity of these processes, simple models that can be used to develop intuitions about the consequences of widespread habitat modification are lacking. Here, we extend the classic Levins metapopulation model to a setting where each of species can colonize patches connected by dispersal, and when patches are vacated via local extinction, they retain a "memory" of the previous occupant-modeling habitat modification. While this model can exhibit a wide range of dynamics, we draw several overarching conclusions about the effects of modification and memory. In particular, we find that any number of species may potentially coexist, provided that each is at a disadvantage when colonizing patches vacated by a conspecific. This notion is made precise through a quantitative stability condition, which provides a way to unify and formalize existing conceptual models. We also show that when patch memory facilitates coexistence, it generically induces a positive relationship between diversity and robustness (tolerance of disturbance). Our simple model provides a portable, tractable framework for studying systems where species modify and react to a shared landscape.
在生命之树上,生物会改变其局部环境,从而使其他物种更适应或更不适应这个环境。尽管这些过程无处不在,但缺乏可以用来形成对广泛的栖息地改变的后果的直观认识的简单模型。在这里,我们将经典的 Levins 复合种群模型扩展到一个可以在其中每个物种都可以在由扩散连接的斑块中定殖的环境中,并且当斑块因本地灭绝而被腾出时,它们会保留前一个占据者的“记忆”-建模栖息地的改变。虽然这个模型可以表现出广泛的动态,但我们对改变和记忆的影响得出了几个总体结论。具体来说,我们发现只要每个物种在殖民由同种生物腾出的斑块时处于劣势,那么任何数量的物种都有可能共存。通过一个定量的稳定性条件,可以精确地表达这个概念,该条件为统一和形式化现有的概念模型提供了一种方法。我们还表明,当斑块记忆有助于共存时,它通常会在多样性和稳健性(对干扰的容忍度)之间产生正相关关系。我们的简单模型为研究物种改变和对共享景观做出反应的系统提供了一个可移植的、易于处理的框架。