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Abstract PremiseTo date, phylogenetic relationships within the monogeneric Brunelliaceae have been based on morphological evidence, which does not provide sufficient phylogenetic resolution. Here we use target‐enriched nuclear data to improve our understanding of phylogenetic relationships in the family. MethodsWe used the Angiosperms353 toolkit for targeted recovery of exonic regions and supercontigs (exons + introns) from low copy nuclear genes from 53 of 70 species inBrunellia, and several outgroup taxa. We removed loci that indicated biased inference of relationships and applied concatenated and coalescent methods to inferBrunelliaphylogeny. We identified conflicts among gene trees that may reflect hybridization or incomplete lineage sorting events and assessed their impact on phylogenetic inference. Finally, we performed ancestral‐state reconstructions of morphological traits and assessed the homology of character states used to define sections and subsections inBrunellia. ResultsBrunelliacomprises two major clades and several subclades. Most of these clades/subclades do not correspond to previous infrageneric taxa. There is high topological incongruence among the subclades across analyses. ConclusionsPhylogenetic reconstructions point to rapid species diversification in Brunelliaceae, reflected in very short branches between successive species splits. The removal of putatively biased loci slightly improves phylogenetic support for individual clades. Reticulate evolution due to hybridization and/or incomplete lineage sorting likely both contribute to gene‐tree discordance. Morphological characters used to define taxa in current classification schemes are homoplastic in the ancestral character‐state reconstructions. While target enrichment data allows us to broaden our understanding of diversification inBrunellia, the relationships among subclades remain incompletely understood.
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Evolutionary bedfellows: Reconstructing the ancestral state of autotomy and regeneration
Abstract Some form of regeneration occurs in all lifeforms and extends from single‐cell organisms to humans. The degree to which regenerative ability is distributed across different taxa, however, is harder to ascertain given the potential for phylogenetic constraint or inertia, and adaptive processes to shape this pattern. Here, we examine the phylogenetic history of regeneration in two groups where the trait has been well‐studied: arthropods and reptiles. Because autotomy is often present alongside regeneration in these groups, we performed ancestral state reconstructions for both traits to more precisely assess the timing of their origins and the degree to which these traits coevolve. Using an ancestral trait reconstruction, we find that autotomy and regeneration were present at the base of the arthropod and reptile trees. We also find that when autotomy is lost it does not re‐evolve easily. Lastly, we find that the distribution of regeneration is intimately connected to autotomy with the association being stronger in reptiles than in arthropods. Although these patterns suggest that decoupling autotomy and regeneration at a broad phylogenetic scale may be difficult, the available data provides useful insight into their entanglement. Ultimately, our reconstructions provide the important groundwork to explore how selection may have played a role during the loss of regeneration in specific lineages.
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- Award ID(s):
- 1846260
- PAR ID:
- 10163147
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Experimental Zoology Part B: Molecular and Developmental Evolution
- Volume:
- 336
- Issue:
- 2
- ISSN:
- 1552-5007
- Format(s):
- Medium: X Size: p. 94-115
- Size(s):
- p. 94-115
- Sponsoring Org:
- National Science Foundation
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