Only one. It's way over my head and I've no time or motivation (in light of other issues) to start a search for a possible hypothesis.
What I really like is for others to do the legwork and serve the condensed knowledge on a silver platter to me and everyone else hahaI can see ecats having to have an ability to be immune to their own discharges (otherwise they'd zap themselves) and hence to the discharges of other ecats. They do look funny and the fat layer might be it. But synos I cannot imagine having such protection. If asked, I'd think that ecats for some reason or other CHOOSE to not zap the synos. This often occurs if there is a synergism of two species. Examples involve cleaner fish not getting eaten by large predators, companion remoras not getting preyed on by their host sharks, cooperation of rift lake cichlids and large catfish such as Bagrus docmak and Bagrus meridionalis, etc.
