Constraints on the Design of Chemical Communication Systems in Terrestrial Vertebrates

Relations between structure, function, and constraint in the chemical communication systems of terrestrial vertebrates are examined from a design-feature perspective. A survey of chemical signals from 34 mammalian species indicates variation in the chemical structure of signals that are used in different social contexts and under different environmental conditions. Behavioral, physiological, and morphological adaptations in the emission and reception of chemical signals in terrestrial vertebrates are reviewed. Several features of chemical signals, including temporal parameters, spatial range, localizability, intensity and detectability, and information content, appear to be adjusted for particular social functions, subject to constraints of the signaling environment. In many cases, these adaptations may minimize energetic costs to signaling animals.