The influence of fragmented landscapes on speciation.

This article investigates how landscape fragmentation and species-specific dispersal ability interact to influence biodiversity patterns, particularly speciation, extinction, and species richness. Using an individual-based microevolutionary model that simulates populations with varying dispersal radii across landscapes characterized by different levels of spatial autocorrelation of suitable habitat patches, the study finds that intermediate dispersal abilities and intermediate fragmentation levels promote the highest species richness. Highly fragmented landscapes reduce total population size and habitat occupancy, especially for species with limited dispersal, while also increasing both speciation and extinction events, leading to greater community turnover. These results support the intermediate dispersal hypothesis and highlight the complex, synergistic effects of spatial configuration and dispersal on evolutionary dynamics, with implications for biodiversity conservation in changing landscapes.