TY - JOUR T1 - Savannah roars: The vocal anatomy and the impressive rutting calls of male impala (Aepyceros melampus) – highlighting the acoustic correlates of a mobile larynx Y1 - 2019 A1 - Frey, Roland A1 - Volodin, Ilya A. A1 - Volodina, Elena V. A1 - Efremova, Kseniya O. A1 - Menges, Vera A1 - Portas, Ruben A1 - Melzheimer, Jörg A1 - Fritsch, Guido A1 - Gerlach, Christina A1 - Dörnberg, Katja KW - Bovidae KW - Felidae KW - formants KW - fundamental frequency KW - larynx retraction KW - mammal KW - polygyny KW - roaring KW - ruminant KW - sexual selection KW - vocal fold KW - vocal posture KW - vocal tract AB -

A retractable larynx and adaptations of the vocal folds in the males of several polygynous ruminants serve for the production of rutting calls that acoustically announce larger than actual body size to both rival males and potential female mates. Here, such features of the vocal tract and of the sound source are documented in another species. We investigated the vocal anatomy and laryngeal mobility including its acoustical effects during the rutting vocal display of free‐ranging male impala (Aepyceros melampus melampus) in Namibia. Male impala produced bouts of rutting calls (consisting of oral roars and interspersed explosive nasal snorts) in a low‐stretch posture while guarding a rutting territory or harem. For the duration of the roars, male impala retracted the larynx from its high resting position to a low mid‐neck position involving an extensible pharynx and a resilient connection between the hyoid apparatus and the larynx. Maximal larynx retraction was 108 mm based on estimates in video single frames. This was in good concordance with 91‐mm vocal tract elongation calculated on the basis of differences in formant dispersion between roar portions produced with the larynx still ascended and those produced with maximally retracted larynx. Judged by their morphological traits, the larynx‐retracting muscles of male impala are homologous to those of other larynx‐retracting ruminants. In contrast, the large and massive vocal keels are evolutionary novelties arising by fusion and linear arrangement of the arytenoid cartilage and the canonical vocal fold. These bulky and histologically complex vocal keels produced a low fundamental frequency of 50 Hz. Impala is another ruminant species in which the males are capable of larynx retraction. In addition, male impala vocal folds are spectacularly specialized compared with domestic bovids, allowing the production of impressive, low‐frequency roaring vocalizations as a significant part of their rutting behaviour. Our study expands knowledge on the evolutionary variation of vocal fold morphology in mammals, suggesting that the structure of the mammalian sound source is not always human‐like and should be considered in acoustic analysis and modelling.

UR - https://onlinelibrary.wiley.com/doi/abs/10.1111/joa.13114 ER - TY - JOUR T1 - High frequency audible calls in northern birch mice Sicista betulina in response to handling: effects of individuality, sex and body mass on the acoustics Y1 - 2019 A1 - Volodin, Ilya A. A1 - Klenova, Anna V. A1 - Ilchenko, Olga G. A1 - Volodina, Elena V. AB -

Objectives
This is the first study of the sonic and ultrasonic vocalization in a Dipodidae rodent. For the small-sized quadrupedal northern birch mouse Sicista betulina, phylogenetically related to the bipedal jerboas (Dipodidae), we report null results for ultrasonic vocalization and investigate the acoustic cues to individual identity, sex and body size in the discomfort-related high-frequency tonal sonic calls.

Results
We used a parallel audio recording in the sonic and ultrasonic ranges during weighting adult northern birch mice before the scheduled hibernation in captivity. The sonic (audible) high-frequency tonal calls (ranging from 6.21 to 9.86 kHz) were presented in all individuals (7 males and 4 females). The ultrasonic calls lacked in the recordings. Two-way nested ANOVA revealed the effects of caller individual identity on all 10 measured acoustic variables and the effects of sex on four out of 10 measured acoustic variables. Discriminant function analyses with 10 acoustic variables included in the analysis showed 85.5% correct assignment of calls to individual and 79.7% correct assignment of calls to sex; both values significantly exceeded the random values (23.1% and 54.3%, respectively) calculated with randomization procedure. Body mass did not differ between sexes and did not correlate significantly with the acoustic variables.

UR - https://bmcresnotes.biomedcentral.com/articles/10.1186/s13104-019-4719-9 ER - TY - JOUR T1 - Phylogenetic relationship and variation of alarm call traits of populations of red‐cheeked ground squirrels ( Spermophilus erythrogenys sensu lato) suggest taxonomic delineation Y1 - 2019 A1 - Matrosova, Vera A. A1 - IVANOVA, Anastasia D. A1 - Volodina, Elena V. A1 - Volodin, Ilya A. A1 - Dmitry Yu. Alexandrov A1 - Sibiryakova, Olga V. A1 - Oleg A. Ermakov KW - alarm call KW - control region KW - cytochrome b KW - mitochondrial DNA KW - vocal communication AB -

Distribution area and taxonomic borders within the species complex Spermophilus erythrogenys sensu lato remain questionable. Early evidence suggests that red‐cheeked ground squirrels of Southeast Kazakhstan are remarkably different in terms of the acoustic structure of their alarm calls from the red‐cheeked ground squirrels of the Kurgan region in Russia. In this study, we analyzed the differences in the acoustic structure of the alarm call and mitochondrial DNA (complete control region, 1005–1006 bp and complete cytochrome b gene, 1140 bp) in 3 populations of red‐cheeked ground squirrels (Tara, Altyn‐Emel and Balkhash), all located within areas isolated by geographical barriers in Southeast Kazakhstan. We found that the alarm call variables were similar between the 3 study populations and differed by the maximum fundamental frequency (8.46 ± 0.75 kHz) from the values (5.62 ± 0.06 kHz) reported for the red‐cheeked ground squirrels from the Kurgan region of Russia. Variation in mtDNA control region was only 3% and variation in cytochrome b gene was only 2.5%. Phylogenetic trees based on cytochrome b gene polymorphism of 44 individuals from the study area and adjacent territories indicated 3 clades with high (98–100%) bootstrap support: “intermedius,” “brevicauda” and “iliensis”). We conclude that the 3 study populations in Southeast Kazakhstan belong to the clade intermedius and suggest a taxonomical revision of the species complex Spermophilus erythrogenys sensu lato, including analyses of nuclear DNA and alarm calls for populations of the brevicauda and iliensis clades.

UR - https://onlinelibrary.wiley.com/toc/17494877/14/4 ER - TY - JOUR T1 - Advertising individual identity by mother and adolescent contact calls in Siberian wapiti Cervus elaphus sibiricus JF - Ethology Y1 - 2018 A1 - Sibiryakova, Olga V. A1 - Volodin, Ilya A. A1 - Volodina, Elena V. ED - Wright, J. AB -

Individualistic contact calls facilitate mother‐offspring reunion after separation. However, in many mammals, both the acoustic structure and individuality of contact calls differ between mother and young. In contrast, in Siberian wapiti Cervus elaphus sibiricus, contact calls are similar in the acoustics between mother and young, whereas effects of this similarity on vocal individuality were not investigated. In this study, we analyzed acoustic differences between closed‐mouth (nasal) and open‐mouth (oral) contact calls and examined individuality of the most usual oral calls of 19 Siberian wapiti (9 hinds and 10 5–6‐month adolescents) emitted in response to mother‐offspring separation. In the oral calls, the values of frequency and power variables were higher than in the nasal calls. Calls of hinds and adolescents did not differ by the maximum fundamental frequency and duration, whereas the peak frequency was higher in the young. Discriminant function analysis (DFA) based on 11 acoustic variables of oral calls accurately classified to individual 92.5% of hind calls and 96.9% of adolescent calls (chi‐square test for differences between hinds and adolescents, p = 0.19). Variables mainly contributing to vocal identity (duration, start, and maximum fundamental frequency) were the same in calls of mothers and adolescents. We conclude that similarities in the acoustics calls of mothers and adolescents mean that they do not differ in their potential for encoding individual identity, suggesting a mutual process of mother‐offspring vocal recognition in Siberian wapiti.

VL - 124 UR - http://doi.wiley.com/10.1111/eth.2018.124.issue-10 IS - 10 JO - Ethology ER - TY - JOUR T1 - Between-year vocal aging in female red deer (Cervus elaphus) JF - BMC Research Notes Y1 - 2018 A1 - Volodin, Ilya A. A1 - Sibiryakova, Olga V. A1 - Vasilieva, Nina A. A1 - Volodina, Elena V. A1 - Matrosova, Vera A. A1 - Garcia, Andrés J. A1 - Pérez-Barbería, Francisco J. A1 - Gallego, Laureano A1 - Landete-Castillejos, Tomás AB -

Objectives

Studying animal vocal aging has potential implication in the field of animal welfare and for modeling human voice aging. The objective was to examine, using a repeated measures approach, the between-year changes of weight, social discomfort score (bites of other hinds on hind pelt), body condition score (fat reserves) and acoustic variables of the nasal (closed-mouth) and the oral (open-mouth) contact calls produced by farmed red deer hinds (Cervus elaphus) toward their young.

Results

Repeated measures ANOVA revealed that with an increase of hind age for 1 year, the acoustic variables of their nasal contact calls (the beginning and maximum fundamental frequencies, the depth of frequency modulation and the peak frequency) decreased, whereas in their oral contact calls only the end fundamental frequency decreased. Duration and power quartiles did not change in any call type. Body weight and body condition score increased between years, whereas discomfort score decreased. Results of this study revealed directly the short-term effects of aging on the acoustics of the nasal contact calls in the same hinds. This study also confirmed that elevated emotional arousal during emission of the oral contact masks the effects of aging on vocalization in female red deer.

VL - 11 UR - https://bmcresnotes.biomedcentral.com/articles/10.1186/s13104-018-3833-4 IS - 1 JO - BMC Res Notes ER - TY - JOUR T1 - Individuality of distress and discomfort calls in neonates with bass voices: Wild-living goitred gazelles ( Gazella subgutturosa) and saiga antelopes ( Saiga tatarica) JF - Ethology Y1 - 2017 A1 - Volodin, Ilya A. A1 - Sibiryakova, Olga V. A1 - Frey, Roland A1 - Efremova, Kseniya O. A1 - Soldatova, Natalia V. A1 - Zuther, Steffen A1 - Kisebaev, Talgat B. A1 - Salemgareev, Albert R. A1 - Volodina, Elena V. KW - acoustic behavior KW - antipredatory strategy KW - emotional arousal KW - mother-offspring communication KW - ruminants KW - vocal identity AB -

Neonate ruminants produce distress calls when captured by a predator and discomfort milk begging calls when hungry. In many neonate ruminants, the distress and discomfort calls are high-frequency vocalizations, in which the fundamental frequency is the key variable for recognition of their emotional arousal by caregivers. In contrast, in this study, we examine the low-frequency open-mouth distress and discomfort calls in the neonates of two species of wild-living ungulates, which clearly highlight vocal tract resonances (formants). In the goitred gazelle (Gazella subgutturosa), the distress calls were higher in fundamental frequency (f0) and in the first and third formants than the discomfort calls. The accuracy of classifying individuals by variables of distress calls with discriminant function analysis (67%) was significantly lower than that of discomfort calls (85%). In the saiga (Saiga tatarica), only the third formant was higher in the distress calls than in the discomfort calls. The accuracy of classifying individuals by variables of distress calls (89%) did not differ significantly from that of discomfort calls (94%). Thus, the use of acoustic cues to vocal identity and to the degree of arousal differs between the two species. Calls were significantly more individualistic in the saiga, probably because this species lives in large herds and neonates use a ‘following’ antipredatory strategy, in which vocal individuality is crucial for mother–offspring communication. In contrast, goitred gazelles live in smaller groups and neonates use a ‘hiding’ antipredatory strategy. Accordingly, mothers can rely on additional environmental cues for spotting their young and this may decrease the necessity for individualization of the calls of neonates.

VL - 123 UR - http://doi.wiley.com/10.1111/eth.2017.123.issue-5 IS - 5 JO - Ethology ER - TY - JOUR T1 - Remarkable vocal identity in wild-living mother and neonate saiga antelopes: a specialization for breeding in huge aggregations? JF - The Science of Nature Y1 - 2017 A1 - Sibiryakova, Olga V. A1 - Volodin, Ilya A. A1 - Frey, Roland A1 - Zuther, Steffen A1 - Kisebaev, Talgat B. A1 - Salemgareev, Albert R. A1 - Volodina, Elena V. KW - maternal care in herds KW - mother-offspring communication KW - offspring survival KW - vocal identity AB -

Saiga antelopes Saiga tatarica tatarica give birth in large aggregations, and offspring follow the herd soon after birth. Herding is advantageous as anti-predator strategy; however, communication between mothers and neonates is strongly complicated in large aggregations. Individual series of nasal and oral contact calls of mother and neonate saiga antelopes were selected from recordings made with automated recording systems placed near the hiding neonates on the saiga breeding grounds in Northern Kazakhstan during synchronized parturitions of 30,000 calving females. We used for comparison of the acoustic structure of nasal and oral contact calls 168 nasal calls of 18 mothers, 192 oral calls of 21 mothers, 78 nasal calls of 16 neonates, and 197 oral calls of 22 neonates. In the oral calls of either mothers or neonates, formant frequencies were higher and the duration was longer than in the nasal calls, whereas fundamental frequencies did not differ between oral and nasal calls. Discriminant function analysis (DFA) based on six acoustic variables, accurately classified individual identity for 99.4% of oral calls of 18 mothers, for 89.3% of nasal calls of 18 mothers, and for 94.4% of oral calls of 18 neonates. The average value of correct classification to individual was higher in mother oral than in mother nasal calls and in mother oral calls than in neonate oral calls; no significant difference was observed between mother nasal and neonate oral calls. Variables mainly responsible for vocal identity were the fundamental frequency and the second and third formants in either mothers or neonates, and in either nasal or oral calls. The high vocal identity of mothers and neonates suggests a powerful potential for the mutual mother-offspring recognition in dense aggregations of saiga antelopes as an important component of their survival strategy.

VL - 104 UR - http://link.springer.com/10.1007/s00114-017-1433-0 IS - 3-4 JO - Sci Nat ER -