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Table 1 . Estimates of fixed effects, with standard errors, from
univariate models and a multivariate model to explain crossing success
in Ruellia (Acanthaceae). A negative coefficient for Allopatry
vs. Sympatry indicates reduced crossing success in sympatry relative to
allopatry. Genetic distance is measured as the branch length separating
two species in a maximum likelihood phylogeny. Asterisks indicate
significance levels from likelihood ratio tests that (1) compare the
likelihood of a model with just the single fixed effect and random
effects for donor and species identity versus a null model with only
random or (2) compare the likelihood of the full model with all fixed
effects and random effects versus a model without the given fixed effect
[p < 0.05 *, p < 0.01 **, p < 0.001
***].