Fig. 4.

Abundance of species across the isolation gradient. Solid lines are species-specific logistic generalized additive models (GAMs) containing a smoothed term for distance. Shared letters indicate a lack of significant difference between GAMs at α = 0.05; * indicates a p-value of 0.053 for the comparison. +++ indicates a significant interaction between distance and abundance at α = 0.005, ++ at 0.05, and + at 0.1. Dashed lines are logistic null models representing the expected abundance of each species in the absence of all competitors. Null models are based on the global model, which includes all species. Points represent sites (n = 17)