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Natalia V. Soldatova - One of the best experts on this subject based on the ideXlab platform.
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the postnatal ontogeny of the sexually dimorphic vocal apparatus in goitred gazelles Gazella subgutturosa
Journal of Morphology, 2016Co-Authors: Kseniya O. Efremova, Natalia V. Soldatova, Ilya A Volodin, Roland Frey, Guido Fritsch, E V VolodinaAbstract:This study quantitatively documents the progressive development of sexual dimorphism of the vocal organs along the ontogeny of the goitred gazelle (Gazella subgutturosa). The major, male-specific secondary sexual features, of vocal anatomy in goitred gazelle are an enlarged larynx and a marked laryngeal descent. These features appear to have evolved by sexual selection and may serve as a model for similar events in male humans. Sexual dimorphism of larynx size and larynx position in adult goitred gazelles is more pronounced than in humans, whereas the vocal anatomy of neonate goitred gazelles does not differ between sexes. This study examines the vocal anatomy of 19 (11 male, 8 female) goitred gazelle specimens across three age-classes, that is, neonates, subadults and mature adults. The postnatal ontogenetic development of the vocal organs up to their respective end states takes considerably longer in males than in females. Both sexes share the same features of vocal morphology but differences emerge in the course of ontogeny, ultimately resulting in the pronounced sexual dimorphism of the vocal apparatus in adults. The main differences comprise larynx size, vocal fold length, vocal tract length, and mobility of the larynx. The resilience of the thyrohyoid ligament and the pharynx, including the soft palate, and the length changes during contraction and relaxation of the extrinsic laryngeal muscles play a decisive role in the mobility of the larynx in both sexes but to substantially different degrees in adult females and males. Goitred gazelles are born with an undescended larynx and, therefore, larynx descent has to develop in the course of ontogeny. This might result from a trade-off between natural selection and sexual selection requiring a temporal separation of different laryngeal functions at birth and shortly after from those later in life. J. Morphol. 277:826-844, 2016. © 2016 Wiley Periodicals, Inc.
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Vocal group signatures in the goitred gazelle Gazella subgutturosa
Animal Cognition, 2014Co-Authors: Ilya A Volodin, Ekaterina N. Lapshina, Kseniya O. Efremova, E V Volodina, Natalia V. SoldatovaAbstract:The potential for vocal modification in mammals has recently been of great interest. This study focuses on the potential for vocal matching in juvenile and adolescent goitred gazelles Gazella subgutturosa that were group housed as part of an animal management programme. Two groups of animals (16 and 19 unrelated individuals, respectively) were recorded at two different ages, juvenile and adolescent, regarding 20–25 calls per individual per age; each group was evaluated in a separate year. Vocal similarity of group members compared to non-members was prominent in both ages, but higher in juveniles. Individual identity was prominent in both ages and higher in adolescents. The more prominent vocal indicators of group membership in juveniles could be related to their higher social dependence compared to adolescents. The more individualized calls of adolescents could be a mechanistic consequence of more stable growth at older age. Our results suggest vocal plasticity of goitred gazelles under social influences. These data add to recent evidence about domestic goat kids Capra hircus, suggesting that vocalizations of species that are not capable of imitation are more flexible than previously thought.
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descended and mobile larynx vocal tract elongation and rutting roars in male goitred gazelles Gazella subgutturosa guldenstaedt 1780
Journal of Anatomy, 2011Co-Authors: Roland Frey, Natalia V. Soldatova, Ilya A Volodin, E V Volodina, Erkin T JuldaschevAbstract: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
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Comparative analysis of reproductive cycles in female Persian gazelle (Gazella subgutturosa subgutturosa) (Central Asia) and sand gazelle (Gazella subgutturosa marica) (Arabian Peninsula).
General and comparative endocrinology, 2001Co-Authors: Antoine J. Sempéré, N. Brown, O.b. Pereladova, André Lacroix, Karim Bahloul, Natalia V. SoldatovaAbstract:This study was conducted at the Bukhara breeding centre (Ouzbekistan, Central Asia) on Persian gazelles (Gazella subgutturosa subgutturosa) and at Thumammah (Saudi Arabia) on sand gazelles (Gazella subgutturosa marica). Plasma prolactin (PRL) and progesterone were determined in groups of females. Because these females were under two different photoperiods (20°N in Saudi Arabia and 40°N in Uzbekistan), some Persian females were treated with melatonin implants. Both groups of females living in natural environment in Uzbekistan and in Saudi Arabia exhibited an estrus (autumn and early winter) and an anestrus season (spring and summer). Both groups of females exhibited estrous and anestrous seasons. The estrous season was shorter in females from Uzbekistan. During the anestrous season, progesterone concentrations remained at basal levels in Persian gazelles (Uzbekistan) while in sand gazelles (Saudi Arabia) hormonal concentrations were higher than in Persian gazelles until August and decreased to similar concentrations in September‐October. Moreover, the pattern of PRL significantly differed in the two groups. Persian gazelles exhibited a clear seasonal pattern with significantly high levels of PRL in June whereas in the sand gazelle PRL did not rise significantly in summer and fluctuated widely. Melatonin treatment significantly depressed PRL concentrations but did not affect the length of the estrous season in Persian gazelles, suggesting that the reproductive cycle was entrained by an endogenous rhythm. © 2001 Academic Press
Torsten Wronski - One of the best experts on this subject based on the ideXlab platform.
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Factors driving Arabian gazelles (Gazella arabica) in Israel to extinction: time series analysis of population size and juvenile survival in an unexploited population
Biodiversity and Conservation, 2019Co-Authors: Benny Shalmon, Ping Sun, Torsten WronskiAbstract:Wild populations of Arabian gazelles ( Gazella arabica ) were once common on the Arabian Peninsula, but today disappeared from large parts of their former range. In Israel only a small population of currently 30 individuals survived, although it was—and still is—well protected from illegal hunting and habitat destruction. In our study we aimed to identify the factors influencing the population growth of G. arabica in Israel over the last two decades (1995–2017). We tested the impact of five environmental variables including annual mean maximum temperature, rainfall, the availability of two major food plants, competition with sympatric dorcas gazelle ( G. dorcas ) and predation (mainly by wolves) on two dependent variables relating to population viability (population size, percentage fawn survival) using a retrospective time series analysis. After testing for autocorrelations, two generalized least squares (GLS) models with autocorrelations at 3 and 6 years [GLS-AR(3, 6)] were identified as the best models to explain environmental effects on populations size. Wolf encounter rate had a significant negative effect on G. arabica population size, while G. dorcas population size had a significant positive effect, suggesting that wolf predation shapes the population size of both gazelle species. For percentage fawn survival, model residuals did not reveal any significant autocorrelation and the best fit GLS-AR(0) model retained only wolf encounter rate and mean annual maximal temperature as significant predictors. This result suggests a strong impact of wolf predation and increasing temperatures on the fawn survival of Arabian gazelles. Changed rainfall patterns, food availability and competition between gazelle species had no impact on fawn survival.
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dark grey gazelles Gazella cetartiodactyla bovidae in arabia threatened species or domestic pet
Hystrix-italian Journal of Mammalogy, 2017Co-Authors: Torsten Wronski, Hannes Lerp, Eva Verena Baermann, Thomas M Butynski, Martin PlathAbstract:True gazelles (genus Gazella) are a prime example of a mammalian group with considerable taxonomic confusion. This includes the descriptions of several dark grey taxa of questionable validity. Here, we examined captive dark grey putative Neumann’s gazelle Gazella erlangeri. Our concerted efforts to retrieve mitochondrial sequence information from old museum specimens of two dark grey gazelles, putative G. erlangeri and putative Muscat gazelle G. muscatensis, were unsuccessful. We did, however, find the mtDNA haplotypes of extant putative G. erlangeri to be nested within the haplotype variation of the Arabian gazelle G. arabica. The observed population genetic divergence between G. arabica and putative G. erlangeri (based on 11 nuclear microsatellites) was driven by genetic impoverishment of putative G. erlangeri. These results, along with morphological signatures of domestication (e.g., reduced brain case size), suggest genetic bottle necks and domestication effects as a consequence of prolonged captive breeding. Three hypotheses are discussed: (a) G. erlangeri and/or G. muscatensis are valid species but are now extinct; (b) one or both taxa represent phenotypic variation within G. arabica and, therefore, are synonyms of G. arabica; and (c) captive stocks, exhibiting the effects of domestication and inbreeding, are the sources for the descriptions of G. erlangeri and G. muscatensis. As concerns the conservation of gazelles, based on current knowledge, we strongly advise against using putative G. erlangeri for any introduction initiative but recommend the continued captive management of putative G. erlangeri.
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Data on phylogenetic analyses of gazelles (genus Gazella) based on mitochondrial and nuclear intron markers
Data in brief, 2016Co-Authors: Hannes Lerp, Torsten Wronski, Sebastian Klaus, Stefanie Allgöwer, Markus Pfenninger, Martin PlathAbstract:The data provided is related to the article “Phylogenetic analyses of gazelles reveal repeated transitions of key ecological traits and provide novel insights into the origin of the genus Gazella” [1]. The data is based on 48 tissue samples of all nine extant species of the genus Gazella, namely Gazella Gazella, Gazella arabica, Gazella bennettii, Gazella cuvieri, Gazella dorcas, Gazella leptoceros, Gazella marica, Gazella spekei, and Gazella subgutturosa and four related taxa (Saiga tatarica, Antidorcas marsupialis, Antilope cervicapra and Eudorcas rufifrons). It comprises alignments of sequences of a cytochrome b data set and of six nuclear intron markers. For the latter new primers were designed based on cattle and sheep genomes. Based on these alignments phylogenetic trees were inferred using Bayesian Inference and Maximum Likelihood methods. Furthermore, ancestral character states (inferred with BayesTraits 1.0) and ancestral ranges based on a Dispersal-Extinction-Cladogenesis model were estimated and results׳ files were stored within this article.
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a morphometric and genetic framework for the genus Gazella de blainville 1816 ruminantia bovidae with special focus on arabian and levantine mountain gazelles
Zoological Journal of the Linnean Society, 2013Co-Authors: Torsten Wronski, Eva V. Bärmann, Saskia Börner, Dirk Erpenbeck, Gertrud E. Rössner, Hannes Lerp, Beatriz Azanza, Gert WörheideAbstract:Gazella is one of the most species-rich genera within horned ruminants. Despite overall similarity in body size and morphology, gazelles show variability in coloration and horn morphology. Unfortunately, however, species differentiation based on these characters, or on discrete skull characters, is very difficult due to high intraspecific variability. Furthermore, most species have fragmented and allopatric distributions, so that species boundaries were hard to define in the past. Mitochondrial DNA sequences have proven useful for investigating gazelle taxonomy in recent years, but especially for old museum material, i.e. type specimens, destructive sampling is often impossible. We provide a comprehensive morphometric framework for the genus Gazella based on linear skull measurements reconciled with results from molecular phylogenetic analysis based on the largest dataset available so far. In particular for males, the skull morphology shows interspecific differences concurrent with DNA data and provides a reliable tool for species identification. Based on morphometric data we synonymize G. karamii with G. marica, and confirm the identification of the G. arabica and G. a. rueppelli type skulls from analyses of mitochondrial DNA sequences. © 2013 The Linnean Society of London
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Food preferences and tooth wear in the sand gazelle (Gazella marica)
Mammalian Biology, 2013Co-Authors: Ellen Schulz, Thomas M. Kaiser, Sven Fraas, Peter L. Cunningham, Khairi Ismail, Torsten WronskiAbstract:Food preferences of the sand gazelle ( Gazella marica ) from the Mahazat as-Sayd Protected Area in Saudi Arabia were evaluated using focal animal sampling in conjunction with an eco-morphological method examining two parameters of tooth wear, i.e., occlusal relief and cusp shape. Observations of live, free-ranging animals ( n = 53) showed that sand gazelles generally consumed more grass (58.4%) than browse (41.6%). However, during the dry season, gazelles spent significantly more time browsing (51.0%) and less time grazing (49.0%) than under wet conditions (browsing: 17.6%; grazing: 82.4%). Thus, consistent with predictions, sand gazelles are intermediate feeders but shift towards browsing when grass is scarce. The mesowear signature of the sand gazelle is consistent with a grazing signal in other ruminants. In other words, the browse component of the diets of live animals was not reflected in the tooth wear. This could have occurred because browse is less abrasive than grass, but more likely because all food types are heavily abrasive in this dusty habitat. We conclude that the sand gazelle population in Mahazat as-Sayd encounters a highly abrasive diet, which has implications for their ability to meet nutritional demands.
Hannes Lerp - One of the best experts on this subject based on the ideXlab platform.
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Repeated hybridization of two closely related gazelle species (Gazella bennettii and Gazella subgutturosa) in central Iran.
Ecology and evolution, 2020Co-Authors: Davoud Fadakar, Hannes Lerp, Mansoureh Malekian, Mahmoud R. Hemami, Hamid R. Rezaei, Eva V. BärmannAbstract:Interspecific hybridization increasingly occurs in the course of anthropogenic actions, such as species translocations and introductions, and habitat modifications or occurs in sympatric species due to the shortage of conspecific mates. Compared with anthropogenically caused hybridization, natural hybridization is more difficult to prove, but both play an important role in conservation. In this study, we detected hybridization of two gazelle sister species, Gazella bennettii (adapted to dry areas) and Gazella subgutturosa (adapted to open plains), in five habitat areas, where G. bennettii naturally occur in central Iran. The hybrids have a nuclear genomic identity (based on two introns), habitat preference, and phenotype of G. bennettii, but the mitochondrial identity (based on cyt b) of G. subgutturosa. We suggest that natural hybridization of female G. subgutturosa and male G. bennettii happened twice in central Iran in prehistoric times, based on the haplotype pattern that we found. However, we found indications of recent hybridization between both species under special circumstances, for example, in breeding centers, due to translocations, or in areas of sympatry due to the shortage of conspecific mates. Therefore, these two species must be kept separately in the breeding centers, and introduction of one of them into the habitat of the other must be strictly avoided.
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dark grey gazelles Gazella cetartiodactyla bovidae in arabia threatened species or domestic pet
Hystrix-italian Journal of Mammalogy, 2017Co-Authors: Torsten Wronski, Hannes Lerp, Eva Verena Baermann, Thomas M Butynski, Martin PlathAbstract:True gazelles (genus Gazella) are a prime example of a mammalian group with considerable taxonomic confusion. This includes the descriptions of several dark grey taxa of questionable validity. Here, we examined captive dark grey putative Neumann’s gazelle Gazella erlangeri. Our concerted efforts to retrieve mitochondrial sequence information from old museum specimens of two dark grey gazelles, putative G. erlangeri and putative Muscat gazelle G. muscatensis, were unsuccessful. We did, however, find the mtDNA haplotypes of extant putative G. erlangeri to be nested within the haplotype variation of the Arabian gazelle G. arabica. The observed population genetic divergence between G. arabica and putative G. erlangeri (based on 11 nuclear microsatellites) was driven by genetic impoverishment of putative G. erlangeri. These results, along with morphological signatures of domestication (e.g., reduced brain case size), suggest genetic bottle necks and domestication effects as a consequence of prolonged captive breeding. Three hypotheses are discussed: (a) G. erlangeri and/or G. muscatensis are valid species but are now extinct; (b) one or both taxa represent phenotypic variation within G. arabica and, therefore, are synonyms of G. arabica; and (c) captive stocks, exhibiting the effects of domestication and inbreeding, are the sources for the descriptions of G. erlangeri and G. muscatensis. As concerns the conservation of gazelles, based on current knowledge, we strongly advise against using putative G. erlangeri for any introduction initiative but recommend the continued captive management of putative G. erlangeri.
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Data on phylogenetic analyses of gazelles (genus Gazella) based on mitochondrial and nuclear intron markers
Data in brief, 2016Co-Authors: Hannes Lerp, Torsten Wronski, Sebastian Klaus, Stefanie Allgöwer, Markus Pfenninger, Martin PlathAbstract:The data provided is related to the article “Phylogenetic analyses of gazelles reveal repeated transitions of key ecological traits and provide novel insights into the origin of the genus Gazella” [1]. The data is based on 48 tissue samples of all nine extant species of the genus Gazella, namely Gazella Gazella, Gazella arabica, Gazella bennettii, Gazella cuvieri, Gazella dorcas, Gazella leptoceros, Gazella marica, Gazella spekei, and Gazella subgutturosa and four related taxa (Saiga tatarica, Antidorcas marsupialis, Antilope cervicapra and Eudorcas rufifrons). It comprises alignments of sequences of a cytochrome b data set and of six nuclear intron markers. For the latter new primers were designed based on cattle and sheep genomes. Based on these alignments phylogenetic trees were inferred using Bayesian Inference and Maximum Likelihood methods. Furthermore, ancestral character states (inferred with BayesTraits 1.0) and ancestral ranges based on a Dispersal-Extinction-Cladogenesis model were estimated and results׳ files were stored within this article.
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a morphometric and genetic framework for the genus Gazella de blainville 1816 ruminantia bovidae with special focus on arabian and levantine mountain gazelles
Zoological Journal of the Linnean Society, 2013Co-Authors: Torsten Wronski, Eva V. Bärmann, Saskia Börner, Dirk Erpenbeck, Gertrud E. Rössner, Hannes Lerp, Beatriz Azanza, Gert WörheideAbstract:Gazella is one of the most species-rich genera within horned ruminants. Despite overall similarity in body size and morphology, gazelles show variability in coloration and horn morphology. Unfortunately, however, species differentiation based on these characters, or on discrete skull characters, is very difficult due to high intraspecific variability. Furthermore, most species have fragmented and allopatric distributions, so that species boundaries were hard to define in the past. Mitochondrial DNA sequences have proven useful for investigating gazelle taxonomy in recent years, but especially for old museum material, i.e. type specimens, destructive sampling is often impossible. We provide a comprehensive morphometric framework for the genus Gazella based on linear skull measurements reconciled with results from molecular phylogenetic analysis based on the largest dataset available so far. In particular for males, the skull morphology shows interspecific differences concurrent with DNA data and provides a reliable tool for species identification. Based on morphometric data we synonymize G. karamii with G. marica, and confirm the identification of the G. arabica and G. a. rueppelli type skulls from analyses of mitochondrial DNA sequences. © 2013 The Linnean Society of London
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Phylogenetic analysis of mitochondrial DNA sequences reveals polyphyly in the goitred gazelle ( Gazella subgutturosa )
Conservation Genetics, 2010Co-Authors: Timothy Wacher, Torsten Wronski, Osama B. Mohammed, Sawsan A. Omer, William Macasero, Robert L. Hammond, Bruce Winney, Mark J. Blacket, Kris J. Hundertmark, Hannes LerpAbstract:Goitred gazelle (Gazella subgutturosa) rank among the most endangered mammals on the Arabian Peninsula and the Asian steppes. Past conservation efforts have been plagued by confusion about the phylogenetic relationship among various—phenotypically discernable—populations, and even the question of species boundaries was far from being certain. This lack of knowledge had a direct impact on conservation measures, especially ex situ breeding programmes, hampering the assignment of captive stocks to potential conservation units. Here, we provide a phylogenetic framework, based on the analysis of mtDNA sequences of a number of individuals collected from the wild and captivity throughout the species’ natural range. Our analyses revealed a polyphyly within the presumed species of G. subgutturosa resulting in two distinct clades: one on the Arabian Peninsula, Iraq, Jordan, Syria and Turkey (Gazella marica; sand gazelle) and one genetically diverse larger clade from the rest of its Asian range (G. subgutturosa; goitred gazelle). Additionally, we provide a quick method (PCR-RFLP) to analyse the taxonomic affiliation of captive gazelles that will be used for re-introductions into the wild.
Antoine J. Sempéré - One of the best experts on this subject based on the ideXlab platform.
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Comparative Analysis of Reproductive Cycles in Female Persian Gazelle (Gazella subgutturosa subgutturosa) (Central Asia) and Sand Gazelle (Gazella subgutturosa marica) (Arabian Peninsula)
General and Comparative Endocrinology, 2001Co-Authors: Antoine J. Sempéré, N. Brown, O.b. Pereladova, Karim Balhoul, André Lacroix, N. SoldatovaAbstract:This study was conducted at the Bukhara breeding centre (Ouzbekistan, Central Asia) on Persian gazelles (Gazella subgutturosa subgutturosa) and at Thumammah (Saudi Arabia) on sand gazelles (Gazella subgutturosa marica). Plasma prolactin (PRL) and progesterone were determined in groups of females. Because these females were under two different photoperiods (20°N in Saudi Arabia and 40°N in Uzbekistan), some Persian females were treated with melatonin implants. Both groups of females living in natural environment in Uzbekistan and in Saudi Arabia exhibited an estrus (autumn and early winter) and an anestrus season (spring and summer). Both groups of females exhibited estrous and anestrous seasons. The estrous season was shorter in females from Uzbekistan. During the anestrous season, progesterone concentrations remained at basal levels in Persian gazelles (Uzbekistan) while in sand gazelles (Saudi Arabia) hormonal concentrations were higher than in Persian gazelles until August and decreased to similar concentrations in September–October. Moreover, the pattern of PRL significantly differed in the two groups. Persian gazelles exhibited a clear seasonal pattern with significantly high levels of PRL in June whereas in the sand gazelle PRL did not rise significantly in summer and fluctuated widely. Melatonin treatment significantly depressed PRL concentrations but did not affect the length of the estrous season in Persian gazelles, suggesting that the reproductive cycle was entrained by an endogenous rhythm.
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Comparative analysis of reproductive cycles in female Persian gazelle (Gazella subgutturosa subgutturosa) (Central Asia) and sand gazelle (Gazella subgutturosa marica) (Arabian Peninsula).
General and comparative endocrinology, 2001Co-Authors: Antoine J. Sempéré, N. Brown, O.b. Pereladova, André Lacroix, Karim Bahloul, Natalia V. SoldatovaAbstract:This study was conducted at the Bukhara breeding centre (Ouzbekistan, Central Asia) on Persian gazelles (Gazella subgutturosa subgutturosa) and at Thumammah (Saudi Arabia) on sand gazelles (Gazella subgutturosa marica). Plasma prolactin (PRL) and progesterone were determined in groups of females. Because these females were under two different photoperiods (20°N in Saudi Arabia and 40°N in Uzbekistan), some Persian females were treated with melatonin implants. Both groups of females living in natural environment in Uzbekistan and in Saudi Arabia exhibited an estrus (autumn and early winter) and an anestrus season (spring and summer). Both groups of females exhibited estrous and anestrous seasons. The estrous season was shorter in females from Uzbekistan. During the anestrous season, progesterone concentrations remained at basal levels in Persian gazelles (Uzbekistan) while in sand gazelles (Saudi Arabia) hormonal concentrations were higher than in Persian gazelles until August and decreased to similar concentrations in September‐October. Moreover, the pattern of PRL significantly differed in the two groups. Persian gazelles exhibited a clear seasonal pattern with significantly high levels of PRL in June whereas in the sand gazelle PRL did not rise significantly in summer and fluctuated widely. Melatonin treatment significantly depressed PRL concentrations but did not affect the length of the estrous season in Persian gazelles, suggesting that the reproductive cycle was entrained by an endogenous rhythm. © 2001 Academic Press
Duncan Mitchell - One of the best experts on this subject based on the ideXlab platform.
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Does size matter? Comparison of body temperature and activity of free-living Arabian oryx (Oryx leucoryx) and the smaller Arabian sand gazelle (Gazella subgutturosa marica) in the Saudi desert
Journal of Comparative Physiology B, 2012Co-Authors: Robyn Sheila Hetem, Willem Maartin Strauss, Linda Gayle Fick, Shane Kevin Maloney, Leith Carl Rodney Meyer, Mohammed Shobrak, Andrea Fuller, Duncan MitchellAbstract:Heterothermy, a variability in body temperature beyond the normal limits of homeothermy, is widely viewed as a key adaptation of arid-adapted ungulates. However, desert ungulates with a small body mass, i.e. a relatively large surface area-to-volume ratio and a small thermal inertia, are theoretically less likely to employ adaptive heterothermy than are larger ungulates. We measured body temperature and activity patterns, using implanted data loggers, in free-ranging Arabian oryx ( Oryx leucoryx , ±70 kg) and the smaller Arabian sand gazelle ( Gazella subgutturosa marica , ±15 kg) inhabiting the same Arabian desert environment, at the same time. Compared to oryx, sand gazelle had higher mean daily body temperatures ( F _1,6 = 47.3, P = 0.0005), higher minimum daily body temperatures ( F _1,6 = 42.6, P = 0.0006) and higher maximum daily body temperatures ( F _1,6 = 11.0, P = 0.02). Despite these differences, both species responded similarly to changes in environmental conditions. As predicted for adaptive heterothermy, maximum daily body temperature increased ( F _1,6 = 84.0, P
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does size matter comparison of body temperature and activity of free living arabian oryx oryx leucoryx and the smaller arabian sand gazelle Gazella subgutturosa marica in the saudi desert
Journal of Comparative Physiology B-biochemical Systemic and Environmental Physiology, 2012Co-Authors: Robyn Sheila Hetem, Willem Maartin Strauss, Linda Gayle Fick, Shane Kevin Maloney, Leith Carl Rodney Meyer, Mohammed Shobrak, Andrea Fuller, Duncan MitchellAbstract:Heterothermy, a variability in body temperature beyond the normal limits of homeothermy, is widely viewed as a key adaptation of arid-adapted ungulates. However, desert ungulates with a small body mass, i.e. a relatively large surface area-to-volume ratio and a small thermal inertia, are theoretically less likely to employ adaptive heterothermy than are larger ungulates. We measured body temperature and activity patterns, using implanted data loggers, in free-ranging Arabian oryx (Oryx leucoryx, ±70 kg) and the smaller Arabian sand gazelle (Gazella subgutturosa marica, ±15 kg) inhabiting the same Arabian desert environment, at the same time. Compared to oryx, sand gazelle had higher mean daily body temperatures (F 1,6 = 47.3, P = 0.0005), higher minimum daily body temperatures (F 1,6 = 42.6, P = 0.0006) and higher maximum daily body temperatures (F 1,6 = 11.0, P = 0.02). Despite these differences, both species responded similarly to changes in environmental conditions. As predicted for adaptive heterothermy, maximum daily body temperature increased (F 1,6 = 84.0, P < 0.0001), minimum daily body temperature decreased (F 1,6 = 92.2, P < 0.0001), and daily body temperature amplitude increased (F 1,6 = 97.6, P < 0.0001) as conditions got progressively hotter and drier. There were no species differences in activity levels, however, both gazelle and oryx showed a biphasic or crepuscular rhythm during the warm wet season but shifted to a more nocturnal rhythm during the hot dry season. Activity was attenuated during the heat of the day at times when both species selected cool microclimates. These two species of Arabian ungulates employ heterothermy, cathemerality and shade seeking very similarly to survive the extreme, arid conditions of Arabian deserts, despite their size difference.
