Ecomorphological convergence in planktivorous surgeonfishes

Handle URI:
http://hdl.handle.net/10754/621451
Title:
Ecomorphological convergence in planktivorous surgeonfishes
Authors:
Friedman, S. T.; Price, S. A.; Hoey, Andrew; Wainwright, P. C.
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
KAUST Department:
Biological and Environmental Sciences and Engineering (BESE) Division; Environmental Science and Engineering Program; Red Sea Research Center (RSRC)
Citation:
Friedman 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.
Publisher:
Wiley-Blackwell
Journal:
Journal of Evolutionary Biology
Issue Date:
26-Jan-2016
DOI:
10.1111/jeb.12837
Type:
Article
ISSN:
1010-061X
Sponsors:
The 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.
Appears in Collections:
Articles; Red Sea Research Center (RSRC); Environmental Science and Engineering Program; Biological and Environmental Sciences and Engineering (BESE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorFriedman, S. T.en
dc.contributor.authorPrice, S. A.en
dc.contributor.authorHoey, Andrewen
dc.contributor.authorWainwright, P. C.en
dc.date.accessioned2016-11-03T08:29:38Z-
dc.date.available2016-11-03T08:29:38Z-
dc.date.issued2016-01-26en
dc.identifier.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.en
dc.identifier.issn1010-061Xen
dc.identifier.doi10.1111/jeb.12837en
dc.identifier.urihttp://hdl.handle.net/10754/621451-
dc.description.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 Biologyen
dc.description.sponsorshipThe 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.en
dc.publisherWiley-Blackwellen
dc.subjectAcanthuridaeen
dc.subjectAdaptive peaken
dc.subjectEvolutionary modellingen
dc.subjectFunctional morphologyen
dc.subjectPhylogenetic comparative methodsen
dc.titleEcomorphological convergence in planktivorous surgeonfishesen
dc.typeArticleen
dc.contributor.departmentBiological and Environmental Sciences and Engineering (BESE) Divisionen
dc.contributor.departmentEnvironmental Science and Engineering Programen
dc.contributor.departmentRed Sea Research Center (RSRC)en
dc.identifier.journalJournal of Evolutionary Biologyen
dc.relation.referencesFriedman, S. T., Price, S. A., Hoey, A. S., & Wainwright, P. C. (2016). Data from: Ecomorphological convergence in planktivorous surgeonfishes (Version 1) [Data set]. Dryad Digital Repository. https://doi.org/10.5061/dryad.r7490en
dc.relation.referencesDOI:10.5061/DRYAD.R7490en
dc.relation.referencesHANDLE:http://hdl.handle.net/10754/624190en
dc.contributor.institutionDepartment of Evolution and Ecology; University of California; Davis CA USAen
dc.contributor.institutionARC Centre of Excellence for Coral Reef Studies; James Cook University; Townsville Qld Australiaen
kaust.authorHoey, Andrewen
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