Similar to male humans, Homo sapiens, the males of a few polygynous ruminants -red deer Cervus elaphus, fallow deer Dama dama and Mongolian gazelle Procapra gutturosa -have a more or less enlarged, low-resting larynx and are capable of additional dynamic vocal tract elongation by larynx retraction during their rutting calls. The vocal correlates of a large larynx and an elongated vocal tract, a low fundamental frequency and low vocal tract resonance frequencies, deter rival males and attract receptive females. The males of the polygynous goitred gazelle, Gazella subgutturosa, provide another, independently evolved, example of an enlarged and low-resting larynx of high mobility. Relevant aspects of the rutting behaviour of territorial wild male goitred gazelles are described. Video and audio recordings served to study the acoustic effects of the enlarged larynx and vocal tract elongation on male rutting calls. Three call types were discriminated: roars, growls and grunts. In addition, the adult male vocal anatomy during the emission of rutting calls is described and functionally discussed using a 2D-model of larynx retraction. The combined morphological, behavioural and acoustic data are discussed in relation to the hypothesis of sexual selection for male-specific deep voices, resulting in convergent features of vocal anatomy in a few polygynous ruminants and in human males.

Like many other gazelles, goitred gazelles (Gazella subgutturosa) are capable of calling either through the nose or through the open mouth. In particular, juvenile goitred gazelles provide a convenient model for contrasting acoustic characteristics of nasal and oral calls, and for estimating their communicative functions. In this study, acoustic variables (formants, fundamental frequency, duration and power quartiles) of 480 oral and 483 nasal calls, recorded from 20 (9 male, 11 female) individually identified captive juvenile goitred gazelles, were examined for their potential to encode sex and identity of the caller. Discriminant function analysis revealed an equally high potential of oral and nasal calls to encode sex, whereas encoding the individual identity was significantly more accurate for oral calls. Sex was encoded exclusively in formants, whilst individual identity was encoded in a combination of all investigated variables. No correlation was found between body mass and values of any acoustic variable. Analyses controlling for age and sex revealed higher average values for all investigated variables of oral calls compared to nasal calls. We discuss the results in relation to the source‐filter theory, mother–offspring communication and production mechanisms of nasal and oral calls in mammals.

In goitred gazelles (Gazella subgutturosa), sexual dimorphism of larynx size and position is reminiscent of the case in humans, suggesting shared features of vocal ontogenesis in both species. This study investigates the ontogeny of nasal and oral calls in 23 (10 male and 13 female) individually identified goitred gazelles from shortly after birth up to adolescence. The fundamental frequency (f0) and formants were measured as the acoustic correlates of the developing sexual dimorphism. Settings for LPC analysis of formants were based on anatomical dissections of 5 specimens. Along ontogenesis, compared to females, male f0 was consistently lower both in oral and nasal calls and male formants were lower in oral calls, whereas the first two formants of nasal calls did not differ between sexes. In goitred gazelles, significant sex differences in f0 and formants appeared as early as the second week of life, while in humans they emerge only before puberty. This result suggests different pathways of vocal ontogenesis in the goitred gazelles and in humans.

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