Open Collections

Zhan, Shing Hei; Drori, Michal; Goldberg, Emma E.; Otto, Sarah P.; Mayrose, Itay

<b>Abstract</b><br/>Premise of the study: Polyploidization is a common and recurring phenomenon in plants and is often thought to be a mechanism of "instant speciation." Whether polyploidization is associated with the formation of new species ("cladogenesis") or simply occurs over time within a lineage ("anagenesis") has never, however, been assessed systematically. Methods: Here, we tested this hypothesis using phylogenetic and karyotypic information from 235 plant genera (mostly angiosperms). We first constructed a large database of combined sequence and chromosome number data sets using an automated procedure. We then applied likelihood models (ClaSSE) that estimate the degree of synchronization between polyploidization and speciation events in maximum likelihood and Bayesian frameworks. Key results: Our maximum likelihood analysis indicated that 35 genera supported a model that includes cladogenetic transitions over a model with only anagenetic transitions, whereas three genera supported a model that incorporates anagenetic transitions over one with only cladogenetic transitions. Furthermore, the Bayesian analysis supported a preponderance of cladogenetic change in four genera but did not support a preponderance of anagenetic change in any genus. Conclusions: Overall, these phylogenetic analyses provide the first broad confirmation that polyploidization is temporally associated with speciation events, suggesting that it is indeed a major speciation mechanism in plants, at least in some genera.; <b>Usage notes</b><br /><div class="o-metadata__file-usage-entry"><h4 class="o-heading__level3-file-title">PloiDB</h4><div class="o-metadata__file-description">Phylogenetic trees inferred using MrBayes, ploidy estimates using ChromEvol, and TPL-based genus species diversity estimates for 223 genera.</div><div class="o-metadata__file-name">ploidb_dryad.tar.gz</br></div></div>

Dataset

2020-06-30

This dataset is made available under a Creative Commons CC0 license with the following additional/modified terms and conditions: CC0 Waiver

https://doi.org/10.5683/SP2/F3YDVP

https://creativecommons.org/publicdomain/zero/1.0/