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  • Phylogenomic analyses re‐examine the evolution of reinforcement and hypothesized hybrid speciation in Phlox wildflowers
Title: Phylogenomic analyses re‐examine the evolution of reinforcement and hypothesized hybrid speciation in Phlox wildflowers
Summary The tree of life is riddled with reticulate evolutionary histories, and some clades, such as the eastern standingPhlox, appear to be hotspots of hybridization. In this group, there are two cases of reinforcement and nine hypothesized hybrid species. Given their historical importance in our understanding of plant speciation, the relationships between these taxa and the role of hybridization in their diversification require genomic validation.Using phylogenomic analyses, we resolve the evolutionary relationships of the eastern standingPhloxand evaluate hypotheses about whether and how hybridization and gene flow played a role in their diversification.Our results provide novel resolution of the phylogenetic relationships in this group, including paraphyly across some taxa. We identify gene flow during one case of reinforcement and find genomic support for a hybrid lineage underlying one of the five hypothesized homoploid hybrid speciation events. Additionally, we estimate the ancestries of four allotetraploid hybrid species.Our results are consistent with hybridization contributing to diverse evolutionary outcomes within this group; although, not as extensively as previously hypothesized. This study demonstrates the importance of phylogenomics in evaluating hypothesized evolutionary histories of non‐model systems and adds to the growing support of interspecific genetic exchange in the generation of biodiversity.  more » « less
Award ID(s):
1844906
PAR ID:
10559885
Author(s) / Creator(s):
; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
New Phytologist
Volume:
243
Issue:
1
ISSN:
0028-646X
Page Range / eLocation ID:
451 to 465
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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