how to identify male and female in black ghost fish
Black ghost knifefish Each species has a characteristic EOD baseline frequency range, which varies with sex and age within the species, as well. The baseline frequency is maintained to be almost constant at stable temperature, but will usually be changed due to the presence of others of the same species. Such changes in frequency relevant to social interaction are called frequency modulations (FMs). The role these FMs have in communication is significant, as black ghost knifefish have developed jamming avoidance responses, which are behavioral responses that avoid the overlapping of EOD frequencies between conspecific individuals to prevent sensory confusion.[7] Moreover, a study was conducted that focused on sexual dimorphism in electrocommunication signals. Female black ghost knifefish generate EODs at a higher frequency than the males, an FM which can be used for gender recognition.[5] A study found the subdominant black ghost knifefish exhibited noticeable gradual frequency rises (GFRs) in their EODs whereas the dominant fish did not, supporting the researchers' hypothesis that GFRs during communication are indicative of submissive signals.[7]