A case of natural triploidy in European diploid green toad (Bufo viridis), with some distributional records of diploid and tetraploid toads

A triploid female (3n = 33) was found in diploid species Bufo viridis from the Crimea Peninsula, Ukraine. The case is recognized as an occasional autotriploidy. No morphological differences were found between this triploid female and other diploid specimens of the sample. Three categories of triploids in the Bufo viridis group are classified. Based on six green toad samples identified by chromosome number, the distribution of diploid and polyploid toads in Kazakhstan is discussed

Spatial distribution of Marmota baibacina and M. sibirica (Marmota, Sciuridae, Rodentia) in a zone of sympatry in Mongolian Altai: Bioacoustic analysis

The spatial distribution of two marmot species Marmota baibacina and M. sibirica in a zone of coexistence was studied by using their alarm call as a diagnostic trait. It was found that M. baibacina prefers to inhabit bouldery screes, whereas M. sibirica inhabits all suitable biotopes. The difference in biotopic distribution of these species could be explained by M. sibirica forcing M. baibacina out of optimum habitats. Cases of coexistence of both species in one family group sites were registered, which might contribute to the appearance of hybrids. © 2010 Pleiades Publishing, Ltd

Сравнительный анализ звукового предупреждающего об опасности сигнала разных возрастных и половых групп рыжеватого суслика (Spermophilus major Pallas 1778)

The formation of the time-frequency characteristics of the alarm call at different stages of individual development was studied on the example of the Russet ground squirrel (S. major). The hypothesis about the vocalizations of young individuals of ground squirrels at lower frequencies than adults was tested. The results of the study indicate a differentiated formation of the sound signal in different sexes of Russet ground squirrel in postnatal ontogenesis. The sound signal in females is formed during the first year of life at the season of activity, and in males at the next year – after the first hibernation. In terms of studied signal parameters, the voice of adult females is higher than that of young animals of both sexes, and that of adult males is lower. The possible causes and significance of the identified sexual and age features of the alarm call of the Russet ground squirrel are discussed.На примере большого суслика (S. major) изучалось формирование частотно-временных характеристик звукового сигнала на разных стадиях индивидуального развития. Проверялась гипотеза о вокализации молодых особей наземных беличьих на более низких частотах, чем у взрослых. Результаты исследования свидетельствуют о дифференцированном формировании звукового сигнала у разных полов большого суслика в постнатальном онтогенезе. Звуковой сигнал у самок формируется в течение первого года жизни в период сезона активности, а у самцов на следующий год – после первой зимней спячки. По совокупности исследованных параметров сигнала голос взрослых самок выше, чем у молодых сусликов обоих полов, а взрослых самцов – ниже. Обсуждаются возможные причины и значение выявленных половых и возрастных особенностей звукового сигнала большого суслика

Spatial distribution of Marmota baibacina and M. sibirica (Marmota, Sciuridae, Rodentia) in a zone of sympatry in Mongolian Altai: Bioacoustic analysis

The spatial distribution of two marmot species Marmota baibacina and M. sibirica in a zone of coexistence was studied by using their alarm call as a diagnostic trait. It was found that M. baibacina prefers to inhabit bouldery screes, whereas M. sibirica inhabits all suitable biotopes. The difference in biotopic distribution of these species could be explained by M. sibirica forcing M. baibacina out of optimum habitats. Cases of coexistence of both species in one family group sites were registered, which might contribute to the appearance of hybrids. © 2010 Pleiades Publishing, Ltd

Comparative Analysis of the Alarm Call in Different Age and Sexual Groups of the Russet Ground Squirrel (Spermophilus major Pallas 1778)

The formation of the alarm call's time-frequency characteristics at different stages of individual development was studied on the russet ground squirrel (S. major). The hypothesis about the vocalizations of young individuals of ground squirrels being emitted at lower frequencies than those of adults was tested. The results of the study indicate a differentiated formation of the sound signal in the different sexes of the russet ground squirrel in postnatal ontogenesis. The sound signal in females is formed in the first year of life during the season of activity, whereas it is formed in males in the year following the first hibernation. In terms of the studied call parameters, the voice of adult females is higher than that of young animals of both sexes, while the voice of adult males is lower. The possible causes and significance of the identified sex and age features of the alarm call of the russet ground squirrel are discussed

Unusual use of two types of alarm call by the long-tailed ground squirrel (Spermophilus undulatus, Rodentia, Sciuridae)

Alarm call of long-tailed ground squirrel (Spermophilus undulatus (Pallas 1778)) was tape recorded in the field and its time-frequency characteristics were analyzed. It is known there are two types of signal, the first one is a short (0.05-0.08 s) broad frequency chat while another is a longer (0.13 s) descending narrow frequency whistle. Previously, it was thought that two signals are discrete and reflect the nature of hazard: broad frequency chat is given upon the approach of a ground predator and narrow frequency whistle is given upon the approach of an aerial predator (Nikolski, Wallschlager, 1982). Further observations showed that both types of signal could be issued upon both ground and aerial predators. Stimuli that cause applying of some type of signal remains unclear

Unusual use of two types of alarm call by the long-tailed ground squirrel (Spermophilus undulatus, Rodentia, Sciuridae)

Alarm call of long-tailed ground squirrel (Spermophilus undulatus (Pallas 1778)) was tape recorded in the field and its time-frequency characteristics were analyzed. It is known there are two types of signal, the first one is a short (0.05-0.08 s) broad frequency chat while another is a longer (0.13 s) descending narrow frequency whistle. Previously, it was thought that two signals are discrete and reflect the nature of hazard: broad frequency chat is given upon the approach of a ground predator and narrow frequency whistle is given upon the approach of an aerial predator (Nikolski, Wallschlager, 1982). Further observations showed that both types of signal could be issued upon both ground and aerial predators. Stimuli that cause applying of some type of signal remains unclear

A Study of Hybridization Between Marmota baibacina and M. sibirica in Their Secondary Contact Zone in Mongolian Altai

The role of hybridization as one of the factors of speciation in mammals has been underestimated for a long time, but now there is a lot of data on its impact in mammalian evolution. Hybridization of species often occurs in their secondary contact zones, which is a natural model for testing factors that ensure species integrity. Studies of hybrid zones are increasingly revealing the essential role of ecological and behavioral features both in initiating crossbreeding and in maintaining interspecific barriers. We studied the hybridization of two species of marmots Marmota baibacina and M. sibirica in the zone of sympatry in Mongolian Altai Mountains. We used a bioacoustic approach to determine the localization of individuals of different species and their cohabitation sites. Genetic typing with two diploid nuclear markers and one marker each of paternal and maternal lines was used to identify hybrids. Habitat preferences of marmots were studied to understand the conditions for the formation of heterospecific pairs. We found a high proportion of hybrid individuals in boulder screes where conditions for the formation of heterospecific pairs probably exist. Our data indicate the viability and fertility of F1 hybrids and their descendants. We hypothesize that the environmental preferences and behavioral features of both species of marmots are important factors that both create conditions for hybridization and limit hybrid dispersal. © Copyright © 2021 Brandler, Kapustina, Nikol’skii, Kolesnikov, Badmaev and Adiya