Phylogenetic reconstruction of the evolutionary relationships among 61 of the 70 species of the parrotfish genera Chlorurus and Scarus (Family Labridae) based on mitochondrial and nuclear gene sequences retrieved 15 well-supported clades with mid Pliocene/Pleistocene diversification. Twenty-two reciprocally monophyletic sister-species pairs were identified: 64% were allopatric, and the remainder were sympatric. Age of divergence was similar for allopatric and sympatric species pairs. Sympatric sister pairs displayed greater divergence in morphology, ecology, and sexually dimorphic colour patterns than did allopatric pairs, suggesting that both genetic drift in allopatric species pairs and ecologically adaptive divergence between members of sympatric pairs have played a role in diversification. Basal species typically have small geographical ranges and are restricted to geographically and ecologically peripheral reef habitats. We found little evidence that a single dominant process has driven diversification, nor did we detect a pattern of discrete, sequential stages of diversification in relation to habitat, ecology, and reproductive biology. The evolution of Chlorurus and Scarus has been complex, involving a number of speciation processes. © 2012 The Linnean Society of London.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This study is dedicated to Dr John E. Randall. Without his instruction on the taxonomy and colour phases of parrotfishes, the first author would not have been able to undertake such a study. Research support was through the Queensland Government/Smithsonian Institution (STRI) Collaborative Funding to J.H.C and D.R.R, the National Geographic Grant Program to J.H.C and D.R.R., and by the JCU internal funding scheme and Program Grants. Logistic support for the sampling program was provided by the Seychelles Fisheries Authority and the research vessel ‘L'Amitie’; the University of Guam Marine Laboratory; West Australian Fisheries, Lizard Island Research Station, (Australian Museum); National Museum Of Marine Science & Technology Taiwan Keelung; Instituto Nacional de Pesca y Acuicultura of Venezuela; the Department of Fisheries, Bahamas; the Bermuda Fisheries Department; the Bermuda Biological Station for Research; Caribbean Marine Research Centre at Lee Stocking Island; Cocos Keeling and Christmas Island National Parks Department of Environment and Heritage Australia; Sultan Qaboos University Oman; King Abdullah University of Science and Technology Saudi Arabia; and Silliman University Marine Laboratory, Philippines. Additional material was provided by Bishop Museum, Hawaii (J. E. Randall, A. Y. Suzumoto) National Museum of Marine Science & Technology Taiwan (Li Shu Chen), The Australian Museum (M. McGrouther), The Western Australian Museum (S. Morrison, G. Allen), D. Bellwood James Cook University, A. M. Ayling Sea Research Queensland, A. Lewis Tevenei Queensland, R. L. Moura, Seção de Peixes, Museu de Zoologia, CP 42594 Universidade de São Paulo, São Paulo, Brazil, Osmar J. Luiz Jr., Departamento de Zoologia e Museu de História Natural, Universidade Estadual de Campinas, Campinas, SP, Brasil, C. E. L. Ferreira, Departamento de Biologia Marinha, Universidade Federal Fluminense, Niterói R. J., Brasil, S. R. Floeter, Laboratório de Biogeografia e Macroecologia Marinha, Universidade Federal de Santa Catarina, Florianópolis S. C., Brasil, A. Halford, J. McIlwain, Sultan Qaboos University, Oman and University of Guam, R. Hamilton, The Nature Conservancy Brisbane. M. Meekan, Australian Institute of Marine Science, T. Hooper, Shoals Program Rodrigues, R. Abesamis, Silliman University. Acknowledgement of use of images: J. E. Randall, FishBase; Paul Humann, Government of US Virgin Islands. Laboratory assistance was provided by Julia Gardiner, Lara Upton, Vanessa Messmer, Lynda Axe, and Line Bay. For assistance with the distributional analyses, we thank Ben Radford, Australian Institute of Marine Science, Jonnell Sanciangco Old Dominion University, and Mia Theresa Comeros IUCN, Kayan Ma, James Cook University. Vivian Ward provided Figs 3 and 5. Analysis of colour patterns was assisted by U. Siebeck and J. Marshall Vision Touch and Hearing Research Centre, University of Queensland. The authors thank Lynda Axe, W. D. Robbins, J. L. Ackerman, and M. Berumen for assistance with the field collections. The manuscript was improved by discussions with D. Carlon, Luiz Rocha, P. Munday, D. Bellwood, R. Bonaldo, Elizabeth Trip, and G. Russ. We wish to thank two anonymous referees for comments on the manuscript. Collections in Australia were made under GBRMPA Permit numbers G01/356 and G03/3871.1 to the School of Marine Biology, James Cook University. The work was carried out under James Cook University Ethics Approval Nos. A503 and A 872-04.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.