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PremisePhylogenetic relationships within major angiosperm clades are increasingly well resolved, but largely informed by plastid data. Areas of poor resolution persist within the Dipsacales, including placement ofHeptacodiumandZabelia, and relationships within the Caprifolieae and Linnaeeae, hindering our interpretation of morphological evolution. Here, we sampled a significant number of nuclear loci using a Hyb‐Seq approach and used these data to infer the Dipsacales phylogeny and estimate divergence times. MethodsSampling all major clades within the Dipsacales, we applied the Angiosperms353 probe set to 96 species. Data were filtered based on locus completeness and taxon recovery per locus, and trees were inferred using RAxML and ASTRAL. Plastid loci were assembled from off‐target reads, and 10 fossils were used to calibrate dated trees. ResultsVarying numbers of targeted loci and off‐target plastomes were recovered from most taxa. Nuclear and plastid data confidently placeHeptacodiumwith Caprifolieae, implying homoplasy in calyx morphology, ovary development, and fruit type. Placement ofZabelia, and relationships within the Caprifolieae and Linnaeeae, remain uncertain. Dipsacales diversification began earlier than suggested by previous angiosperm‐wide dating analyses, but many major splitting events date to the Eocene. ConclusionsThe Angiosperms353 probe set facilitated the assembly of a large, single‐copy nuclear dataset for the Dipsacales. Nevertheless, many relationships remain unresolved, and resolution was poor for woody clades with low rates of molecular evolution. We favor expanding the Angiosperms353 probe set to include more variable loci and loci of special interest, such as developmental genes, within particular clades.
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Uneven missing data skew phylogenomic relationships within the lories and lorikeets.
The resolution of the Tree of Life has accelerated with advances in DNA sequencing technology. To achieve dense taxon sampling, it is often necessary to obtain DNA from historical museum specimens to supplement modern genetic samples. However, DNA from historical material is generally degraded, which presents various challenges. In this study, we evaluated how the coverage at variant sites and missing data among historical and modern samples impacts phylogenomic inference. We explored these patterns in the brush-tongued parrots (lories and lorikeets) of Australasia by sampling ultraconserved elements in 105 taxa. Trees estimated with low coverage characters had several clades where relationships appeared to be influenced by whether the sample came from historical or modern specimens, which were not observed when more stringent filtering was applied. To assess if the topologies were affected by missing data, we performed an outlier analysis of sites and loci, and a data reduction approach where we excluded sites based on data completeness. Depending on the outlier test, 0.15% of total sites or 38% of loci were driving the topological differences among trees, and at these sites, historical samples had 10.9× more missing data than modern ones. In contrast, 70% data completeness was necessary to avoid spurious relationships. Predictive modeling found that outlier analysis scores were correlated with parsimony informative sites in the clades whose topologies changed the most by filtering. After accounting for biased loci and understanding the stability of relationships, we inferred a more robust phylogenetic hypothesis for lories and lorikeets.
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- Award ID(s):
- 1655736
- PAR ID:
- 10290188
- Date Published:
- Journal Name:
- Genome biology and evolution
- Volume:
- 12
- Issue:
- 7
- ISSN:
- 1759-6653
- Page Range / eLocation ID:
- 1131-1147
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1101/398297
