Data from: Limits to species richness in terrestrial communities

Are communities limited by biotic interactions, or are they random draws from regional species pools? One way to tell is to compare total species counts in geographic regions to average counts in ecological samples falling within those regions. If species richness is limited regionally, then the relationship should be curvilinear even in a log-log space. Local data pertaining to trees and 10 groups of animals are analyzed to test this hypothesis. Most relationships are indeed curvilinear. To explain these patterns, a simple model is proposed that invokes biotic interaction-limited speciation or immigration rates combined with extinction or extirpation rates that fall as the number of occupied patches increases. Local and regional richness come into balance as the rates trade off, causing global richness to also be limited. Surprisingly, however, the data for trees break the pattern, suggesting that the great adaptive radiation of seed plants may still be unfolding.

Usage Notes
ReferencesReferences to publications yielding Ecological Register data recordslimits_to_species_richness_references.tar.gzRegistersEcological Register data files for ants, bats, birds, butterflies, dung beetles, frogs, large mammals, lizards, mosquitoes, small mammals, and treeslimits_to_species_richness_registers.tar.gz

群落究竟是受生物相互作用限制，还是仅为区域物种种库的随机抽取样本？解答这一问题的可行路径之一，是对比地理区域内的总物种数与该区域内生态采样的平均物种数量。若物种丰富度受区域限制，则即使在双对数坐标空间中，二者的关系也应呈曲线形态。本研究通过分析树木与10类动物的本地数据检验该假说，结果显示多数关系确实呈现曲线特征。为解释这些观测模式，本文提出一个简单模型：该模型假定生物相互作用限制了物种形成或迁入速率，同时伴随随占据斑块数量增加而降低的灭绝或局部消亡速率。随着上述速率达成权衡平衡，本地与区域物种丰富度将达到均衡，进而导致全球物种丰富度同样受到限制。然而令人意外的是，树木的数据打破了这一模式，这表明种子植物的大型适应性辐射可能仍在进行之中。

使用说明
参考文献
获取可生成生态登记（Ecological Register）数据记录的相关出版物引用信息，请参见limits_to_species_richness_references.tar.gz；涵盖蚂蚁、蝙蝠、鸟类、蝴蝶、蜣螂、青蛙、大型哺乳动物、蜥蜴、蚊子、小型哺乳动物及树木的生态登记数据文件，可通过limits_to_species_richness_registers.tar.gz获取。