Data from: Comparing process-based and constraint-based approaches for modeling macroecological patterns

Ecological patterns arise from the interplay of many different processes, and yet the emergence of consistent phenomena across a diverse range of ecological systems suggests that many patterns may in part be determined by statistical or numerical constraints. Differentiating the extent to which patterns in a given system are determined statistically, and where it requires explicit ecological processes, has been difficult. We tackled this challenge by directly comparing models from a constraint-based theory, the Maximum Entropy Theory of Ecology (METE) and models from a process-based theory, the size-structured neutral theory (SSNT). Models from both theories were capable of characterizing the distribution of individuals among species and the distribution of body size among individuals across 76 forest communities. However, the SSNT models consistently yielded higher overall likelihood, as well as more realistic characterizations of the relationship between species abundance and average body size of conspecific individuals. This suggests that the details of the biological processes contain additional information for understanding community structure that are not fully captured by the METE constraints in these systems. Our approach provides a first step towards differentiating between process- and constraint-based models of ecological systems and a general methodology for comparing ecological models that make predictions for multiple patterns.生态格局源于多种不同过程的相互作用，而在多样的生态系统中普遍存在的一致现象则表明，诸多生态格局在一定程度上可由统计约束或数值约束所决定。长期以来，学界难以区分给定系统中的生态格局在多大程度上由统计过程主导，又在哪些环节需要明确的生态学过程支撑。为此，我们通过直接对比两类理论衍生的模型应对这一挑战：一类是基于约束的生态学最大熵理论（Maximum Entropy Theory of Ecology, METE），另一类是基于过程的体型结构化中性理论（size-structured neutral theory, SSNT）。两类理论衍生的模型均能对76个森林群落中的物种个体分布格局，以及群落内个体体型分布特征进行刻画。但相较而言，SSNT模型始终具备更高的整体似然值，且能更真实地刻画物种多度与同种个体平均体型之间的关联关系。这表明，生物学过程的具体细节蕴含了理解群落结构的额外信息，而这类信息并未被上述系统中的METE约束完全涵盖。本研究为区分生态学系统中基于过程的模型与基于约束的模型迈出了第一步，同时也为对比可针对多种格局做出预测的生态学模型提供了通用方法论。