Abstract
In a study of the individuality in the voice of reindeer calves, sound spectrograms of calls from IO equal-aged calves were analysed. The following variables were selected and measured as to the degree of inter-individual overlapping: A) Duration of the call. B) Fundamental frequency. C-E) Frequency of the first, the second and the third formant. F-G) Difference in frequency between the first and the second and between the second and the third formant. H) The shape of the fundamental. I-K) The shape of the first, the second and the third formant. The variables were considered distinct to a calf if they were overlapped to less than 25 percent by the range of the same variable in another calf. No particular variable characterized the calves throughout, but in relation to any other calf, each was characterized by one or more variables. It is suggested that the call is characterized by interaction of different features, by the "Gestalt" of the call. Although individuality has been shown in the structure of the calls, it has not yet been investigated to what extent the separate individual characteristics are actually recognized as distinctive by the mothers.