A functional approach to ecomorphological patterns of feeding in cottid fishes

Abstract

SynopsisOne of the major goals of an ecomorphological analysis is to correlate patterns of interspecific differences in morphology with patterns of interspecific differences in ecology. Information derived from functional morphological studies may provide a mechanistic framework supporting the correlation, but the move from a correlational relationship to a causal relationship requires experimental evidence that the interspecific morphological differences create performance differences and therefore ecological differences . The goal of this study was to examine ecomorphological relationships in the diets of cottid fishes (Scorpaeniformes : Cottidae) from the northeastern Pacific by using functional classifications of predators (based on their mode of attack) and of prey (based on their anti-predator defenses) . The proposed ecomorphological relationships were tested by examining capture success among the cottids in attacks on prey with different escape abilities . As predicted on functional morphological grounds, both multivariate and univariate analyses indicated that the gravimetric importance of `elusive prey' (i .e . fishes, shrimp, mysids, and octopods) was greater in cottid species with a larger relative mouth size . Supporting a causal link between morphology and ecology, performance tests indicated that larger-mouthed cottids had significantly higher capture success on Heptacarpus shrimp than did smaller-mouthed species . As predicted, there were no differences in capture success among predators regardless of their attack style or ecomorphological patterns in attack on crabs (Cancer and Petrolisthes spp.) when the crabs were presented on a sand surface (i .e .`easy prey') . Several difficulties still exist when trying to apply a functional group approach to ecomorphology. These include the behavioral plasticity of the predators, the confounding factor of evolutionary history in identifying correlated ecomorphological features, multiple morphological solutions to common functional problems, the limitations of traditional dietary studies during extremes of prey abundance, and an inadequate understanding of the anti-predator defenses of most prey, including modifications that occur during ontogeny or in different habitats . IntroductionGlade or assemblage) use a common methodology .

Ecomorphology and use of food resources: inter- and intraspecific relationships of fish fauna associated with macrophyte stands

“…The relationship between body shape and resource use may be related to the evolutionary history of the species (Winemiller, 1991). Thus, morphological patterns in assemblages tend to characterize species groups that explore the same ecological resource -e.g., species in the same trophic guild may present a higher morphological similarity, independently of their phylogenetic distance , since the exploitation of specific food items in an ecosystem can be facilitated by a specific design (Wootton, 1992;Norton & Brainerd, 1993;Gerking, 1994;Norton, 1995;Winemiller, et al, 1995;Montaña & Winemiller, 2009;Sampaio et al, 2013). For this reason, some authors attribute to the morphology the ability to predict the ecological niche -i.e., how the body shape selects the ecological space in a given habitat, and consider that ecomorphology can be used as a tool in analysis of assemblage structure (Winemiller, 1991;Casatti & Castro, 2006;Oliveira et al, 2010;Pagotto et al, 2011).…”

Régime alimentaire de <i>Pomadasys jubelini</i> (Pisces, Haemulidae) dans une lagune Ouest africaine (lagune Ebrié, Côte d\'Ivoire)

“…Plusieurs travaux ont cependant montré qu'il existe une relation directe entre la morphologie du tube digestif et l'écologie alimentaire de certains poissons (Norton, 1995;Winemiller et al, 1995;Adite & Winemiller, 1997;Bouton et al, 1998;Hugueny & Pouilly, 1999;Delariva & Agostinho, 2001). …”

Phenotypic Plasticity of Rutilus Prespensis (Karaman, S., 1924) From Lake Prespa and Lake Skadar

“…Variability in growth, development and maturation creates a variety of body shapes within a species (Cadrin, 2000) that, along with ecological interactions of organism are directly or indirectly influenced by environmental conditions (Norton et al, 1995). In R. prespensis from Lake Skadar, two characteristics (pO and lD) revealed a positive allometric relationship, and ten (h, hc,Oh, iO, lpc, hD, lA, hA, lP and lV) had a negative allometric relationship.…”