Phylogenetic tree data for: Frequent hybridisation between parapatric lekking bird-of-paradise species

Hybridisation is known to occur between a wide range of taxa, including
species for which strong sexual selection has led to markedly different
sexual phenotypes and lek-mating behaviours. To what extent occasional
hybridisation can overcome the reproductive barriers in such systems, and,
for example, lead to the establishment of hybrid zones, is poorly known.
In this study, we address this question by focusing on one of the most
well-known avian radiations in which sexual selection has resulted in an
extraordinary assemblage of phenotypic diversity and lek-mating
behaviours; the birds-of-paradise (Paradisaeidae). We quantify the
genome-wide distribution of introgression and find multiple signals of
recent and historical gene flow between and within two genera of
birds-of-paradise, Astrapia and Paradigalla. In addition, we present the
first empirical genomic evidence of a putative hybrid zone between two
lekking bird-of-paradise species that differ substantially in their
sexually selected traits and behaviours. Our findings are consistent with
the idea that behavioural and phenotypic traits may constitute weaker pre-
and post-zygotic barriers to gene flow than generally thought in
lek-mating species.