Admixture may be extensive among hyperdominant Amazon rainforest tree species

Admixture is a mechanism by which species of long-lived plants may acquire novel alleles. However, the potential role of admixture in the origin and maintenance of tropical plant diversity is unclear. We ask whether admixture occurs in an ecologically important clade of Eschweilera (Parvifolia clade, Lecythidaceae), which includes some of the most widespread and abundant tree species in Amazonian forests.

Using target capture sequencing, we conducted a detailed phylogenomic investigation of 33 species in the Parvifolia clade and investigated specific hypotheses of admixture within a robust phylogenetic framework. We assembled target loci from raw sequence reads, conducted tree-based paralog trimming, and estimated species trees using maximum likelihood approaches. In addition, we called single nucleotide polymorphisms for members of the Parvifolia clade and used a Bayesian clustering approach to estimate the ancestry of individuals. We distinguished between population structure and e...