If the male traang have no eyes, how do they know what image to show to the females? Also, how would they have developed any sort of science or mathematics with this system. Seeing as the females would be the only ones able to receive information, how would they be able to pass on information to other females? Do they have a writing system of sorts? Is it based on the visual language? If there is only visual and no symbolic communication, it hardly seems that they would be able to communicate abstract ideas, especially with other intelligent life.