Fig. 2. Patterns of introgression inferred for the Heliconiinae clade.

a The matrix shows inferred introgression proportions as estimated from scOG gene trees in the introgressed species pairs, and then mapped to internal branches using the f-branch method. The expanded tree at the bottom of the matrix shows both the terminal and ancestral branches. b ASTRAL-III species tree derived from nucleotide gene trees, with mapped introgression events (red arrows) derived from the corresponding f-branch matrix. Yellow dashed arrows indicate introgression events with lower support (triplet support ratio <10%). Branch lengths correspond to coalescent units. Numbers on nodes correspond to the confidence interval of the dated phylogeny (Fig. 1e). Note how, not only, most of the introgression events happen within clades and among time overlapped nodes, but also how the majority of introgressive events are affecting lineages with low CUs, indicating a lower barrier to gene flow. There seems to be only one introgression for H. aoede, which happened with the Silvaniform/Melpomene basal branch. Times inferred from the dating analysis summarized in Fig. 1. c Each segment indicates the confidence interval (CI 95% from Fig. 1c) of the estimated introgression event (triplet support ratio >10%). The circles indicate the average date.