Mbuna-cichlids (from Lake Malawi) form a very complex community. In order to find out whether there is an interspecific communication system and a dominance hierarchy, we started an intra- and interspecific study of Melanochromis auratus, M. johanni [sic], Pseudotropheus "ornatus" and P. lombardoi.
The intraspecific study pointed out that all four species establish a linear rank
order, which answers to strict rules. In interspecific groups (two species) an
interspecific dominance hierarchy was formed, in which the original intraspecific
rank order and colouration were retained.