Add reference Complex organisms are composed of organs and tissues which evolved to their present state as they function together to improve an organism's overall reproductive fitness. Studies of individual organs help us understand their basic functions but this reductionist approach misses the larger context of the whole organism. This problem can be circumvented if all the organs in an organism were comprehensively studied by the same methodology and analyzed together. Using honey bees (Apis mellifera L.) as a model system,we report here the first whole proteome of a complex organism,measuring 29 different tissue types among the three honey bee castes: queen,drone,and worker. The data reveal that,e.g.,workers have a heightened capacity to deal with environmental toxins and queens have a far more robust immune system than their nestmates. Most intriguingly,our analysis reveals the path by which organs of complex organisms probably evolved.Raw data were processed by MaxQuant (v1.2.0.13) using default parameters, plus lysine and N-terminal dimethylation for three isotopologues for relative quantitation. Data were searched against the Apis Official Gene Set version 2 with common contaminants, containing a total of 22037 sequences. Normalized intensity ratios were used for relative quantitation.