Tadpoles behavior plasticity: foraging in different heights in the water column

• Grant number: 17/05194-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2017
• End date: December 31, 2017
• Field of knowledge: Biological Sciences - Ecology
• Principal Investigator: Denise de Cerqueira Rossa-Feres
• Grantee: Paula Maria Rosa
• Host Institution: Instituto de Biociências, Letras e Ciências Exatas (IBILCE). Universidade Estadual Paulista (UNESP). Campus de São José do Rio Preto. São José do Rio Preto , SP, Brazil

Abstract

Tadpoles present large morphological diversity in the shape of the body, in the oral apparatus and in the configuration of the fins. The morphology of tadpoles may represent the position they occupy in the water column, which allowed them to be classified into ecomorphological guilds, such as benthic and nektonic tadpoles. In spite of this great diversity and of being considered organisms with great morphological and behavioral plasticity, neither the degree of plasticity nor the function of the morphological structures are still known, especially in tadpoles of Neotropical anurans. Our objective in this study is to evaluate the plasticity in the feeding behavior of tadpoles of different ecomorphological guilds when food is available at different heights in the water column. The response variables will be metrics of tadpoles (size and biomass) and behavior (time spent to find food, frequency of visits to the substrate and time spent feeding tadpoles). In a second experiment, the foraging preference will be tested when the feed is available simultaneously at the three heights of the water column. Tadpoles that feed on the substrate positioned near the bottom of the aquarium are expected to spend less time to find food, visit the substrate more frequently, and spend less time feeding continuously, and thus have greater body weight and size. In addition, in the selection experiment, tadpoles are expected to have preference for the food positioned in the bottom because, due to the morphology (depressed body and lower fins), it is expected that they will avoid the energy costs of foraging in the water column. (AU)