Psyc 212 | chapter 4 the chemosensory systems: taste and smell: general characteristics of chemosensory perception. Marine organisms needed to seek food and avoid predators. For terrestrial organisms, air is the medium: smell is the distant detector of chemical stimuli and taste is the near detector. Territorial marking is accomplished by by-products of excretion. Sexual signaling occurs by release of chemicals from specialized glands (pheromones) usually in found in the genital areas of organisms. Humans rely much less on the chemosensory system; we rely more on vision and hearing. Smell: - certain emitted odors have pheromonal actions in humans. Infants can detect odors of mother"s breasts and attracted to them, while repulsed by scents of strangers 2. Taste: - still provides survival value since we reject poisonous food bitter or sour. Craving of salt might reflect the fact that we need to make sure we have enough sodium every day inadequate amount leads to cardiac arrest.