KAUST DepartmentBiological and Environmental Sciences and Engineering (BESE) Division
Environmental Science and Engineering Program
Red Sea Research Center (RSRC)
Permanent link to this recordhttp://hdl.handle.net/10754/621451
MetadataShow full item record
Abstract© 2016 European Society For Evolutionary Biology. Morphological convergence plays a central role in the study of evolution. Often induced by shared ecological specialization, homoplasy hints at underlying selective pressures and adaptive constraints that deterministically shape the diversification of life. Although midwater zooplanktivory has arisen in adult surgeonfishes (family Acanthuridae) at least four independent times, it represents a clearly specialized state, requiring the capacity to swiftly swim in midwater locating and sucking small prey items. Whereas this diet has commonly been associated with specific functional adaptations in fishes, acanthurids present an interesting case study as all nonplanktivorous species feed by grazing on benthic algae and detritus, requiring a vastly different functional morphology that emphasizes biting behaviours. We examined the feeding morphology in 30 acanthurid species and, combined with a pre-existing phylogenetic tree, compared the fit of evolutionary models across two diet regimes: zooplanktivores and nonzooplanktivorous grazers. Accounting for phylogenetic relationships, the best-fitting model indicates that zooplanktivorous species are converging on a separate adaptive peak from their grazing relatives. Driving this bimodal landscape, zooplanktivorous acanthurids tend to develop a slender body, reduced facial features, smaller teeth and weakened jaw adductor muscles. However, despite these phenotypic changes, model fitting suggests that lineages have not yet reached the adaptive peak associated with plankton feeding even though some transitions appear to be over 10 million years old. These findings demonstrate that the selective demands of pelagic feeding promote repeated - albeit very gradual - ecomorphological convergence within surgeonfishes, while allowing local divergences between closely related species, contributing to the overall diversity of the clade. Journal of Evolutionary Biology
CitationFriedman ST, Price SA, Hoey AS, Wainwright PC (2016) Ecomorphological convergence in planktivorous surgeonfishes. J Evol Biol 29: 965–978. Available: http://dx.doi.org/10.1111/jeb.12837.
SponsorsThe authors would like to thank Johanna Lee who helped obtain morphometric data from specimens. Funding for this research was provided by National Science Foundation grants IOS-0924489 and DEB-1061981 to PCW, and ARC DE130100688 to ASH.
JournalJournal of Evolutionary Biology
- Adaptive landscape and functional diversity of Neotropical cichlids: implications for the ecology and evolution of Cichlinae (Cichlidae; Cichliformes).
- Authors: Arbour JH, López-Fernández H
- Issue date: 2014 Nov
- The evolution of jaw protrusion mechanics is tightly coupled to bentho-pelagic divergence in damselfishes (Pomacentridae).
- Authors: Cooper WJ, Carter CB, Conith AJ, Rice AN, Westneat MW
- Issue date: 2017 Feb 15
- Rare ecomorphological convergence on a complex adaptive landscape: Body size and diet mediate evolution of jaw shape in squirrels (Sciuridae).
- Authors: Zelditch ML, Ye J, Mitchell JS, Swiderski DL
- Issue date: 2017 Mar
- Local phylogenetic divergence and global evolutionary convergence of skull function in reef fishes of the family Labridae.
- Authors: Westneat MW, Alfaro ME, Wainwright PC, Bellwood DR, Grubich JR, Fessler JL, Clements KD, Smith LL
- Issue date: 2005 May 22
- Piscivory limits diversification of feeding morphology in centrarchid fishes.
- Authors: Collar DC, O'Meara BC, Wainwright PC, Near TJ
- Issue date: 2009 Jun