Epidermal origin of alarm chemical cues in Rhinella arenarum tadpoles

RAICES, M.; JUNGBLUT, L.; PAZ DA; POZZI, AG

Chascomús

Congreso; XVI Jornadas Anuales Sociedad Argentina de Biología; 2014

Sociedad Argentina de Biología

EPIDERMAL ORIGIN OF ALARM CHEMICAL CUES IN Rhinella arenarum TADPOLES Raices M, Jungblut LD, Paz DA, Pozzi AG. Departamento de Biodiversidad y Biología Experimental- FCEyN-UBA (marilina.r@hotmail.com)   Larvae of many anuran taxa display strong behavioral responses to chemical cues, including alarm signals. These behaviors are common in different species, and in Rhinella arenarum include reducing activity, escape behaviors and area avoidance. A common process by which vertebrate prey releases alarm cues is through injury or consumption by a predator. These chemical acts as predation cues for conspecifics. In this work we investigated the tissue source of a chemical cue of predation in Rhinella arenarum tadpoles. We observed that tadpoles responded with antipredator behaviors when exposed to skin and tail homogenates but not to carcass homogenate. Histological analysis of the skin and tail showed a cellular type similar to described in tadpoles of other species, the ?Riecenzellen? or giant cells. These cells are round, oval or pear-shaped and their nucleus lies basally or laterally on the cell membrane. They extend to the surface of the epidermis but have no opening there and are distributed uniformly over the body surface. Apparently they are specialized for synthesis and release of the olfactory alarm pheromone. Our observations support the idea that these cells are the origin of the chemical cue, which induces antipredator behavior in conspecifics. Área temática: Biología Animal