In this book. Stephen Hubbell develops a formal mathematical theory that unifies these two fields. When a speciation process is incorporated into Robert H. MacArthur and Edward O. Wilson's now classical theory of island biogeography, the generalized theory predicts the existence of a universal, dimensionless biodiversity number. In the theory, this fundamental biodiversity number, together with the migration or dispersal rate, completely determines the steady-state distribution of species richness and relative species abundance on local to large geographic spatial scales and short-term to evolutionary time scales. 在这本书中。斯蒂芬·哈贝尔发展了一种将这两个领域统一起来的形式化数学理论。当一个物种形成过程被纳入Robert H。麦克阿瑟和爱德华O。威尔逊现在的经典岛屿生物地理学理论，广义理论预测存在一个普遍的、无量纲的生物多样性数量。在理论上，这个基本的生物多样性数字，连同迁移或扩散率，完全决定了物种丰富度和相对物种丰富度在局部到大地理空间尺度和短期到进化时间尺度上的稳态分布。