Whole brain gene expression profiling for Julidochromis transcriptus male vs. female and Julidochromis marlieri male vs female to identify sex-role biased and sex biased gene expression in these species that exhibit conventional and reversed sex-biased behavior respectively. Overall design: 5 J. transcriptus male vs. female and 5 J. transcriptus female vs. male hybridizations compare 4 males and 4 females in a balanced loop design with dye-swaps that is independent of the 5 J. marlieri male vs. female and 5 J. marlieri female vs. male hybridizations compare 4 males and 4 females also in a balanced loop design with dye swaps.