Phylogenomics of the adaptive radiation of Triturus newts supports gradual ecological niche expansion towards an incrementally aquatic lifestyle

B Wielstra; E McCartney-Melstad; J W Arntzen; R K Butlin; H B Shaffer

doi:10.1016/j.ympev.2018.12.032

Phylogenomics of the adaptive radiation of Triturus newts supports gradual ecological niche expansion towards an incrementally aquatic lifestyle

Mol Phylogenet Evol. 2019 Apr:133:120-127. doi: 10.1016/j.ympev.2018.12.032. Epub 2019 Jan 7.

Authors

B Wielstra¹, E McCartney-Melstad², J W Arntzen³, R K Butlin⁴, H B Shaffer²

Affiliations

¹ Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095, USA; Department of Animal and Plant Sciences, University of Sheffield, S10 2TN Sheffield, UK; Naturalis Biodiversity Center, 2300 RA Leiden, the Netherlands; Institute of Biology Leiden, Leiden University, 2300 RA Leiden, the Netherlands. Electronic address: ben.wielstra@naturalis.nl.
² Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095, USA; La Kretz Center for California Conservation Science, Institute of the Environment and Sustainability, University of California, Los Angeles, CA 90095, USA.
³ Naturalis Biodiversity Center, 2300 RA Leiden, the Netherlands.
⁴ Department of Animal and Plant Sciences, University of Sheffield, S10 2TN Sheffield, UK; Department of Marine Sciences, University of Gothenburg, Gothenburg 405 30, Sweden.

PMID: 30630099
DOI: 10.1016/j.ympev.2018.12.032

Abstract

Newts of the genus Triturus (marbled and crested newts) exhibit substantial variation in the number of trunk vertebrae (NTV) and a higher NTV corresponds to a longer annual aquatic period. Because the Triturus phylogeny has thwarted resolution to date, the evolutionary history of NTV, annual aquatic period, and their potential coevolution has remained unclear. To resolve the phylogeny of Triturus, we generated a c. 6000 transcriptome-derived marker data set using a custom target enrichment probe set, and conducted phylogenetic analyses using: (1) data concatenation with RAxML, (2) gene-tree summary with ASTRAL, and (3) species-tree estimation with SNAPP. All analyses produce the same, highly supported topology, despite cladogenesis having occurred over a short timeframe, resulting in short internal branch lengths. Our new phylogenetic hypothesis is consistent with the minimal number of inferred changes in NTV count necessary to explain the diversity in NTV observed today. Although a causal relationship between NTV, body form, and aquatic ecology has yet to be experimentally established, our phylogeny indicates that these features have evolved together, and suggest that they may underlie the adaptive radiation that characterizes Triturus.

Keywords: Morphology; Phylogeny; Sequence capture; Systematics; Target enrichment; Transcriptome.

Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't

MeSH terms

Animals
Aquatic Organisms / genetics*
Ecosystem*
Genomics*
Geography
Phylogeny*
Species Specificity
Triturus / classification*
Triturus / genetics*

Abstract

Publication types

MeSH terms

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