title: Differential effects of temperature on the feeding kinematics of the tadpoles of two sympatric anuran species.
abstract: Temperature impacts ectotherm performance by influencing many biochemical and physiological processes. When well adapted to their environment, ectotherms should perform most efficiently at the temperatures they most commonly encounter. In the present study, we tested how differences in temperature affects the feeding kinematics of tadpoles of two anuran species: the benthic tadpole of Rhinella schneideri and the nektonic tadpole of Trachycephalus typhonius. Benthic and nektonic tadpoles have segregated distributions within ponds and thus tend to face different environmental conditions, such as temperature. Muscle contractile dynamics, and thus whole organism performance, is primarily temperature dependent for ectotherms. We hypothesized that changes in mean temperatures would have differential effects on the feeding kinematics of these two species. We conducted a laboratory experiment in which we used high-speed videography to record tadpoles foraging at cold and warm temperatures. In general, tadpoles filmed at warm temperatures opened their jaws faster, attained maximum gape earlier, and exhibited shorter gape cycles than tadpoles in cold temperatures, irrespective of species. We also found species x temperature interactions regarding the closing phase velocity, and the percentage of time it takes tadpoles to achieve maximum gape and to start closing their jaws. These interactions could indicate that these two co-occurring species differ in their sensitivity to differences in water temperature and have temperature-dependent feeding strategies that maximize feeding performance in their preferred environment.
authors.affiliation: PPG Ecologia e Evolução, Universidade Federal de Goiás, Goiânia, Goiás, Brazil.
authors.forename: Verônica T T
authors.initials: VT
authors.lastname: de Sousa
authors.affiliation: Departamento de Ecologia, Universidade Federal de Goiás, Goiânia, Goiás, Brazil.
authors.forename: Fausto
authors.initials: F
authors.lastname: Nomura
authors.affiliation: Departamento de Zoologia e Botânica, Universidade Estadual Paulista, São José do Rio Preto, São Paulo, Brazil.
authors.forename: Denise
authors.initials: D
authors.lastname: de C Rossa-Feres
authors.affiliation: Departamento de Biologia, Campus do Bacanga, Universidade Federal do Maranhão, São Luis, Maranhão, Brazil.
authors.forename: Gilda V
authors.initials: GV
authors.lastname: Andrade
authors.affiliation: Departamento de Zoologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Tiago L
authors.initials: TL
authors.lastname: Pezzuti
authors.affiliation: Sir Charles Tupper Medical Building, Department of Medical Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada.|Department of Urologic Sciences, Gordon & Leslie Diamond Care Centre, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Wassersug
authors.affiliation: Department of Biology, Allegheny College, Meadville, Pennsylvania.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Venesky
mesh_terms: D000818:Animals; D001001:Anura / Q000502:physiology*; D001696:Biomechanical Phenomena; D017753:Ecosystem; D005247:Feeding Behavior / Q000502:physiology*; D007814:Larva / Q000502:physiology; D009055:Mouth; D013045:Species Specificity; D013696:Temperature; D014741:Video Recording