Specialized morphology corresponds to a generalist diet: linking form and function in smashing mantis shrimp crustaceans.
Many animals are considered to be specialists because they have feeding structures that are fine-tuned for consuming specific prey. For example, "smasher" mantis shrimp have highly specialized predatory appendages that generate forceful strikes to break apart hard-shelled prey. Anecdotal observations suggest, however, that the diet of smashers may include soft-bodied prey as well. Our goal was to examine the diet breadth of the smasher mantis shrimp, Neogonodactylus bredini, to determine whether it has a narrow diet of hard-shelled prey. We combined studies of prey abundance, feeding behavior, and stable isotope analyses of diet in both seagrass and coral rubble to determine if N. bredini's diet was consistent across different habitat types. The abundances of hard-shelled and soft-bodied prey varied between habitats. In feeding experiments, N. bredini consumed both prey types. N. bredini consumed a range of different prey in the field as well and, unexpectedly, the stable isotope analysis demonstrated that soft-bodied prey comprised a large proportion (29-53 %) of the diet in both habitats. Using a Bayesian mixing model framework (MixSIAR), we found that this result held even when we used uninformative, or generalist, priors and informative priors reflecting a specialist diet on hard-shelled prey and prey abundances in the field. Thus, contrary to expectation, the specialized feeding morphology of N. bredini corresponds to a broad diet of both hard-shelled and soft-bodied prey. Using multiple lines of study to describe the natural diets of other presumed specialists may demonstrate that specialized morphology often broadens rather than narrows diet breadth.
Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA. mdevries@ucsd.edu.|Scripps Institution of Oceanography, University of California, 9500 Gilman Drive # 0202, La Jolla, San Diego, CA, 92093-0202, USA. mdevries@ucsd.edu.
Maya S
MS
deVries
Scripps Institution of Oceanography, University of California, 9500 Gilman Drive # 0202, La Jolla, San Diego, CA, 92093-0202, USA.
Brian C
BC
Stock
Naos Marine Laboratories, Smithsonian Tropical Research Institute, Balboa, Ancón, Panamá, República de Panamá
John H
JH
Christy
Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA.|Ecosystem Fluxes Group, Laboratory for Atmospheric Chemistry, Paul Scherrer Institut, Villigen, 5232, Switzerland.
Gregory R
GR
Goldsmith
Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA.
Todd E
TE
Dawson
D000818:Animals; D001499:Bayes Theorem; D003445:Crustacea; D004032:Diet; D017753:Ecosystem; D005247:Feeding Behavior; D011235:Predatory Behavior
Bayesian mixing model; Feeding ecology; Raptorial appendage; Stable isotopes; Stomatopoda