Influence of sex and larval experience on cognitive performance in a frog
Animals that undergo metamorphosis experience extreme changes in both morphology and ecology. Despite these radical changes, studies in holometabolous insects indicate larval experience and memory can persist through metamorphosis. Despite the interesting questions this raises, this has not yet been investigated in vertebrates that undergo metamorphosis. I used a visual association task in a two-choice Y maze to investigate the learning and retention abilities of tadpoles, and how this prior experience affected learning in a similar task post-metamorphosis. Both tadpoles and frogs failed to learn the association task; however, both improved in the time taken to locate the correct arm with accessible food reward over time. Frogs that had prior experience with the maze task as tadpoles performed better than frogs with no prior maze experience, demonstrating evidence for behavioural retention across metamorphosis in the form of exploration speed as an effect of larval experience. I also investigated sex differences in exploration speed for tadpoles and frogs and found opposing sex-based differences in the two life-stages. As far as I am aware, my results provide the first evidence for an effect of non-chemosensory larval experience on adult performance in amphibians, and the first evidence of sex differences in tadpole behaviour.