We used the “APE,” “GEIGER,” and “LASER” packages (5759) in R (51) to obtain the lineage diversification patterns for each species group. We fitted a total of eight diversification models implementing two constant rates (pure birth and birth-death) and three variable rates (exponential and logistic density-dependent and two-rate pure birth) using LASER 2.4 (57). The SPVAR (time-varying speciation), EXVAR (time-varying extinction), and BOTHVAR (time-varying speciation and extinction) models that allow differential extinction and speciation rates were measured following Rabosky and Lovette (60). The models fit were ranked by comparison of values of ln L, AIC, ΔAIC, and Akaike weight (ωi). We generated lineage-through-time (LTT) plots from our multilocus species trees to visualize the tempo of diversification within each species group. Because we generally used relatively small species trees with less than 10 lineages for each species/species complex to infer LTT plots, one concern is that the number of branches in each tree were not sufficient to detect patterns deviating from a constant rate of diversification. Despite this caveat, 15 of the 23 groups analyzed showed convergent patterns of rate constancy, which is notable considering the total number of lineages analyzed as well as their disparate phylogenetic affinities. Nonetheless, to minimize this potential bias, we further evaluated different models of diversification by combining all species and lineages sampled into a single LTT, following the same approach of the individual analyses (table S3).

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