Ontogenetic shape changes in Pomacentridae (Teleostei, Perciformes) and their relationships with feeding strategies: a geometric morphometric approach
Frederich, B.; Adriaens, D.; Vandewalle, P. (2008). Ontogenetic shape changes in Pomacentridae (Teleostei, Perciformes) and their relationships with feeding strategies: a geometric morphometric approach. Biol. J. Linn. Soc. 95(1): 92-105. dx.doi.org/10.1111/j.1095-8312.2008.01003.x In: Biological Journal of the Linnean Society. Academic Press: London; New York. ISSN 0024-4066; e-ISSN 1095-8312, more | |
Keywords | Allometry Aquatic organisms > Marine organisms > Fish > Marine fish > Reef fish Behaviour > Feeding behaviour Biogeny > Ontogeny Biological development > Larval development Musculoskeletal system > Anatomical structures > Skeleton > Endoskeleton > Bones > Skull Population functions > Growth Dascyllus aruanus (Linnaeus, 1758) [WoRMS]; Perciformes [WoRMS]; Pomacentridae Bonaparte, 1831 [WoRMS]; Pomacentrus pavo (Bloch, 1787) [WoRMS]; Teleostei [WoRMS] ISE, French Polynesia, Society I., Moorea; ISW, Malagasy Rep., Toliara [Marine Regions] Marine/Coastal | Author keywords | allometry; damselfishes; development; feeding apparatus; growth;heterochrony; ontogeny; reef fishes; skull |
Abstract | The present study explores the shape changes of cranial structures directly involved in food capturing during growth after reef settlement in two species of Pomacentridae (Dascyllus aruanus and Pomacentrus pavo). Landmark-based geometric morphometrics were used to study allometric patterns and related shape changes in four skeletal units: neurocranium, suspensorium and opercle, mandible and premaxilla. At settlement, the larvae of both species have a relatively similar morphology, especially with respect to the mandible. Their shapes suggest a feeding mode defined as ram/suction-feeding. Ontogenetic shape changes show a shift to a suction feeding mode of prey capture. The main transformations involved are an increase in height of the suspensorium and the opercle, an elevation of the supraoccipital crest, a relative shortening of the mandible, and a lengthening of the ascending process of the premaxilla. Shape changes of the mandible in the two studied species also reflect an increase of biting capacities. The high disparity between adult shape results from differences in the rate and in the length of ontogenetic trajectories, from divergence of the ontogenetic trajectories (neurocranium, mandible, and premaxilla) and parallel shifts of the trajectories in the size-shape space (suspensorium and opercle). In an evolutionary context, allometric heterochronies during ontogeny of different skeletal unit of the head may be considered as a basis for the explanation of the diversity of damselfishes. |
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