Patterns of spatial autocorrelation in the species richness and spatial decay in composition similarity. (A) Patterns of spatial autocorrelation in the species richness of intertidal and subtidal fishes along the Chilean coast. Spatial autocorrelation is measured as Moran's I index for different distance classes. The dashed line indicates the absence of autocorrelation (i.e., H0: I = 0). The P value indicates the significance of the overall correlogram using the Bonferroni correction for multiple comparisons. (B) Spatial decay in similarity in the composition of fish species increases the geographical distance separating the sites at both intertidal and subtidal habitats. The r value corresponds to Mantel coefficient, and P value corresponds to its significance assessed with 1,000 permutations of the Euclidean distance matrix.