Bees, odor sensing

Danty E., Arnold G., Huet J.-C., Masson C. and Pemollet J.-C. (1998) Separation, characterization and sexual heterogeneity of multiple putative odorant-binding proteins in the honey bee Apis mellifera L. (Hymenoptera Apidea). Chem. Senses 23, 83-91. 

Distantly related plants, such as rose, jasmin, and lavender have quite independently gone down this road of complexity, based on different groups of chemical constituents. We may conclude, therefore, that complexity of odor has evolved as being the most effective way of evoking a desired response from an animal with the ability to smell and the ability to memorize odor. What is remarkable is that the particular combinations of materials that individual flowers produce to make up their fragrance have, to our own sense of smell, an identity far greater than a random mixture of as many ill-assorted chemicals. Perhaps we may infer from this, in view of the similarity of our receptor cells, that the balance of materials is as important to the olfactory mechanism of the bee as it is to our own in producing a sense of identity and aesthetic pleasure. 

An odor warning of air pollutant exposure is provided to man and many animals by the olfactory membranes, another example of a biological indicator. In specially trained dogs, the sense of smell can rival the sensitivity of the most sophisticated instrumentation [41, 42]. Tamed bees have also been used to locate mines and explosives without hazard, and can be trained to seek out target chemicals in waste dump sites [43]. 

Fig. 8,5 Discrimination increases with concentration for dissimilar odors (b) but not for similar odors (a). Conditioning and testing were performed at the same concentration for the similar (a n = 87 animals) or dissimilar (b n - 88 animals) test odors. Generalization response levels to novel odors (open columns) are shown next to the response to the conditioned odor (shaded column) at a given training/testing concentration. Reproduced from Wright and Smith, Different thresholds for detection and discrimination of odors in the honey bee Apis melUfera). Chemical Senses, 2004, vol. 29, pp. 127-135 with permission of the Oxford University Press.

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