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941.
In neonate ruminants, the acoustic structure of vocalizations may depend on sex, vocal anatomy, hormonal profiles and body mass and on environmental factors. In neonate wild-living Mongolian gazelles Procapra gutturosa, hand-captured during biomedical monitoring in the Daurian steppes at the Russian-Mongolian border, we spectrographically analysed distress calls and measured body mass of 22 individuals (6 males, 16 females). For 20 (5 male, 15 female) of these individuals, serum testosterone levels were also analysed. In addition, we measured relevant dimensions of the vocal apparatus (larynx, vocal folds, vocal tract) in one stillborn male Mongolian gazelle specimen. Neonate distress calls of either sex were high in maximum fundamental frequency (800–900 Hz), but the beginning and minimum fundamental frequencies were significantly lower in males than in females. Body mass was larger in males than in females. The levels of serum testosterone were marginally higher in males. No correlations were found between either body mass or serum testosterone values and any acoustic variable for males and females analysed together or separately. We discuss that the high-frequency calls of neonate Mongolian gazelles are more typical for closed-habitat neonate ruminants, whereas other open-habitat neonate ruminants (goitred gazelle Gazella subgutturosa, saiga antelope Saiga tatarica and reindeer Rangifer tarandus) produce low-frequency (<200 Hz) distress calls. Proximate cause for the high fundamental frequency of distress calls of neonate Mongolian gazelles is their very short, atypical vocal folds (4 mm) compared to the 7-mm vocal folds of neonate goitred gazelles, producing distress calls as low as 120 Hz.  相似文献   
942.
Journal of Material Cycles and Waste Management - The current study aimed to determine the characteristics and kinetic parameters for the pyrolysis of printed circuit board (PCB) wastes including...  相似文献   
943.
Russian Journal of Ecology - The long-term dynamics (over more than 70 years) of pike infection by cestodes Triaenophorus crassus and T. nodulosus in the Rybinsk Reservoir (the Volga River) has...  相似文献   
944.
Russian Journal of Ecology - A study of the anthropogenic impacts on the on-shore aggregation of true seals was carried out at a haul-out located at the mouth of Piltun Bay (the northeastern part...  相似文献   
945.
Russian Journal of Ecology - To test the hypothesis that animals from habitats exposed to high anthropogenic pressure are more successful in adapting to captivity, immature narrow-skulled voles...  相似文献   
946.
Russian Journal of Ecology - Climate change entails shifts in the ranges of woody plants along both latitudinal and altitudinal gradients in the boreal forest biome. In this study,...  相似文献   
947.
Environment, Development and Sustainability - The COVID-19 pandemic has caused a global emergence, and the absence of a proven vaccine or medicine has led to the implementation of measures to...  相似文献   
948.
Environment, Development and Sustainability - Local residents near forests often collect non-timber forest products (NTFPs) for a variety of reasons, including food, medicine, firewood, religious...  相似文献   
949.
Environment, Development and Sustainability - Good air quality is highly essential to the well-being of mankind, all living organisms and the environment. The quality of air is degrading at a...  相似文献   
950.
Environmental Economics and Policy Studies - The classical DICE model is a widely accepted integrated assessment model for the joint modeling of economic and climate systems, where all model state...  相似文献   
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