Meeting Abstract
The use of nudibranchs as experimental species for adult neuroethology has been pivotal to elucidating the basis of animal behavior.. These shell-less molluscs are particularly suited to such investigations, given their distinguishable swimming and crawling behaviors and accessible sensory organs. However, little is known about early life stages: how the neural system controls their behavior during embryonic, larval, and juvenile stages remains unclear, mostly due to the intractability of embryos in species currently used for behavioral studies. Understanding the link between neuronal development and animal behavior at early life stages is essential to comparing juvenile and adult behaviors. Therefore, we have established the aeolid nudibranch, Berghia stephanieae, as an experimental system; this species’ embryos are accessible, enabling us to study all stages of its brain’s development. We report on methodology for labeling the central nervous system with various antibodies that recognize neurotransmitters, and describe the expression patterns of neurotransmitters in the brain during the early juvenile stage. We found that the post-metamorphic juvenile brain is organized similarly to the adult brain of nudibranch neuroethological models. The cerebropleural ganglia are positioned dorsally to the pedal and buccal ganglia. Acetylated Tubulin-Like Immunoreactivity localizes in neurons connecting the oral tentacles, buccal ganglia, and rhinophores to the anterior end of the cerebropleural ganglion, and in neurons extending posteriorly to the ciliated foot. These neurons are visible under differential interference contrast microscopy. These results provide a starting point for building a clearer picture of the neuroanatomy of post-metamorphic B. stephanieae, and allow for future neuroethological studies.
