title: Adaptive radiation and ecological opportunity in Sulawesi and Philippine fanged frog (Limnonectes) communities.
abstract: Because island communities are derived from mainland communities, they are often less diverse by comparison. However, reduced complexity of island communities can also present ecological opportunities. For example, amphibian diversity on Sulawesi Island is lower than it is in the Philippines, but Sulawesi supports a surprising diversity of Sulawesi fanged frogs (Limnonectes). Here we examine molecular, morphological, and geographical variation of fanged frogs from these two regions. Using genealogical concordance, morphology, and a Bayesian approach to species delimitation, we identified 13 species on Sulawesi, only four of which have been previously described. After evolutionary history is accounted for, a model with multiple body size optima in sympatric species is favored over a "random-walk" model of body size evolution. Additionally, morphological variation is higher among sympatric than nonsympatric species on Sulawesi but not in the Philippines. These findings suggest that adaptive radiation of fanged frogs on Sulawesi was driven by natural selection to infiltrate ecological niches occupied by other frog lineages in the Philippines. This supports a role of ecological opportunity in community assembly: diversification in mature communities, such as the Philippines, is limited by a dearth of unoccupied ecological niches. On Sulawesi, evolutionary novelties originated in a predictable and replicated fashion in response to opportunities presented by a depauperate ancestral community.
authors.affiliation: Center for Environmental Genomics, Department of Biology, McMaster University, Hamilton, Ontario L8S 4K1, Canada.
authors.forename: Mohammad I
authors.initials: MI
authors.lastname: Setiadi
authors.forename: Jimmy A
authors.initials: JA
authors.lastname: McGuire
authors.forename: Rafe M
authors.initials: RM
authors.lastname: Brown
authors.forename: Mohammad
authors.initials: M
authors.lastname: Zubairi
authors.forename: Djoko T
authors.initials: DT
authors.lastname: Iskandar
authors.forename: Noviar
authors.initials: N
authors.lastname: Andayani
authors.forename: Jatna
authors.initials: J
authors.lastname: Supriatna
authors.forename: Ben J
authors.initials: BJ
authors.lastname: Evans
mesh_terms: D000818:Animals; D044822:Biodiversity; D005075:Biological Evolution; D049628:Body Size; D004272:DNA, Mitochondrial / Q000235:genetics; D017753:Ecosystem; D003576:Electron Transport Complex IV / Q000235:genetics; D005260:Female; D016654:Genes, RAG-1 / Q000235:genetics; D049810:Genetic Speciation; D007214:Indonesia; D008297:Male; D008969:Molecular Sequence Data; D010679:Philippines; D010802:Phylogeny; D012335:RNA, Ribosomal / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D011898:Ranidae / Q000033:anatomy & histology* / Q000235:genetics* / Q000502:physiology; D012641:Selection, Genetic; D017421:Sequence Analysis
chemical_list: D004272:DNA, Mitochondrial; D012335:RNA, Ribosomal; D012336:RNA, Ribosomal, 16S; C075526:RNA, ribosomal, 12S; D003576:Electron Transport Complex IV