From Gondwana to the Yellow Sea, evolutionary diversifications of true toads Bufo sp. in the Eastern Palearctic and a revisit of species boundaries for Asian lineages
- Ewha Womans University, Republic of Korea
- Russian Academy of Sciences, Russian Federation
- Federal Scientific Center of the East Asia Terrestrial Biodiversity Far Eastern Branch of Russian Academy of Sciences, Russian Federation
- University of Toronto, Canada
- Nanjing Forestry University, China
- Universidade do Porto, Portugal
- Kyoto University, Japan
- Tokyo University of Agriculture and Technology, Japan
- National Chung Hsing University, Taiwan
- Chinese Culture University, Taiwan
Abstract
Taxa with vast distribution ranges often display unresolved phylogeographic structures and unclear taxonomic boundaries resulting into hidden diversity. This hypothesis-driven study reveals the evolutionary history of Bufonidae, covering the phylogeographic patterns found in Holarctic bufonids from the West Gondwana to the phylogenetic taxonomy of Asiatic true toads in the Eastern Palearctic. We used an integrative approach relying on fossilised birth-death calibrations, population dynamic, gene-flow, species distribution and species delimitation modelling to resolve the biogeography of the clade and highlight cryptic lineages. We verified the near-simultaneous Miocene radiations within Western and Eastern Palearctic Bufo, c. 14.49 - 10.00 Mya, temporally matching with the maximum dust outflows in Central Asian deserts. Contrary to earlier studies, we demonstrated that the combined impacts of long dispersal and ice-age refugia equally contributed to the current genetic structure of Bufo in East Asia. Our findings reveal a climate-driven adaptation in septentrional Eastern Asian Bufo, explained its range shifts towards northern latitudes. We resolve species boundaries within the Eastern Palearctic Bufo, and redefine the taxonomic and conservation units of the northeastern species: B. sachalinensis and its subspecies.
Data availability
All data generated or analysed during this study are either included in the manuscript and supporting files, or submitted online depositories. All Sequences generated in present study deposited to the Genbank database [https://www.ncbi.nlm.nih.gov/ 927 genbank/] under the accession number MW081664- MW081847 (CR), MW467646-MW467777 (ND2), MW489915-MW489964 (POMC), MW489986-MW490035 (RAG-1), MW507752-MW507780 (Rho). Input files in the form of BEAST XML generated for all molecular dating analyses and species delimitation modelling are available from the Mendeley Data repository http://dx.doi.org/10.17632/wdtw6kn2t4.1 (Othman et al., 2021).
Article and author information
Author details
Funding
Korean Environmental Industry and Technology Institute (KEITI 2017002270003)
- Yikweon Jang
Foreign Youth Talent Program (QN2021014013L)
- Amaël Borzée
Russian Foundation of Basic Research (20-04-00918)
- Spartak N Litvinchuk
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Sampling in the Republic of Korea were collected in 2017 under the Ministerial authorisation number 2017-16, and the samples from Jirisan National Park were collected under the Ministerial authorisation number 2019-01. Samples from the People's Republic of China were collected under the authorisation provided by Nanjing Forestry University. IACUC permit is not required for the in-situ experiment in this study, in accord to the rules of Ewha Woman's University Institutional Biosafety Committee
Copyright
© 2022, Othman et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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From Gondwana to the Yellow Sea, evolutionary diversifications of true toads Bufo sp. in the Eastern Palearctic and a revisit of species boundaries for Asian lineages
eLife 11:e70494.
https://doi.org/10.7554/eLife.70494
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