Evaluating Early-Life Behavioral Responses to Social Cues in Cichlid Fish

Abstract

Social behavior can vary across development stages. An animal may prefer to affiliate with a protective parent, groups of peers, or be solitary depending on its age and needs. Cichlid fish are powerful models to study social behavior due to their robust sociality, rapid diversification and genetic tractability. Many mature social behaviors and signaling pathways have been characterized in the cichlid Astatotilapia burtoni. Juvenile A. burtoni (fry) behavior is less understood. Studying fry behavior elucidates early social affiliations, granting ecological significance for survival and social organization as well as a model for the evolution and mechanisms of early behavior. We present fry with social stimuli in a two-choice assay, allowing chemosensory and visual perception to determine if they seek their mother or siblings (kin). We expect fry to prefer their mother or kin over another choice, determined by time spent close to one stimulus over the other. Testing n=4 trials for preference of mother vs. male, our results indicate overall that fry do not show a clear preference for their mother. However, preference shifts with age suggest an onset window for maternal preference with neurosensory maturation. Testing n=6 trials of kin versus non-kin, n=6 trials of kin vs. heterospecifics, and n=2 trials of large vs. small kin groups, our results indicate that fry seek peer groups, but cannot discern their kin from other fry. We propose a model that particular social preferences shift with fry development stages. Further research may test preference onsets with age, determine the influential sensory modalities for fry behavior and their associated neural activity patterns.