Marmota Sibirica Research Articles

Parallelism in Speciation and Intraspecific Diversification of the Plague Microbe <i>Yersinia pestis</i>

Modern “molecular genetic (MG) phylogenies” of the plague microbe Yersinia pestis, built on models of neutral evolution using statistical methods of phylogenetic analysis, contradict numerous obvious environmental (ECO) patterns and are not consistent with the concept of adaptatiogenesis. The reason for the discrepancy between MG and ECO phylogenies is seen in the underestimation by the MG approach of parallelisms in the processes of speciation and intraspecific diversification of the plague microbe. ECO methods showed the parallel tritope (almost) simultaneous speciation of three primary genovariants (populations, subspecies) Y. pestis 2.ANT3, 3.ANT2 and 4.ANT1 in three geographical populations of the Mongolian marmot (Marmota sibirica), which in the MG approach is mistaken for polytomy (“Big Bang”), caused by unknown natural phenomena on the eve of the first pandemic (Justinian’s plague, 6th-8th centuries AD). The discrepancy between MG and ECO interpretations of the evolution of intraspecifically-derived phylogenetic sub-branches 0.PE and 2.MED is also associated with parallel evolutionary processes in independent lines, based on genovariants 2.ANT3, 3.ANT2 and 4.ANT1. Independence of these phylogenetic lines and associated with them parallelisms of sub-branches 0.PE and 2.MED are not taken into account in the MG approach. The prospect of creating a real phylogenetic tree for Y. pestis depends on a creative synthesis of the two approaches – MG and ECO.

Ecological scenario of the plague microbe <i>Yersinia pestis</i> speciation underlying adequate molecular evolutionary model

It is known that the psychrophilic pseudotuberculosis microbe serotype 1 (Y. pseudotuberculosis 0:1b) causing Far East scarlet-like fever (FESLF) an intestinal infection found in a wide range of invertebrates and vertebrates inhabiting cold regions in the Northern and Central Asia as well as Far East is direct ancestor of the plague causative agent Yersinia pestis. However, the mechanism of Y. pestis speciation remains poorly elucidated. Numerous Y. pestis phylogenies created by using molecular genetic (MG) technologies are largely contradictory, being not in line with reliable data obtained by natural science approaches (e.g., ecology, epizootology, biogeography, and paleontology), which disagree with current evolutionary doctrine (synthetic theory of evolution). The MG approach provides no definitive answer to the questions of where, when, how, and under what circumstances the species Y. pestis arose. One of the reasons for such situation might be due to inadequacy of using the molecular evolutionary model for Y. pestis phylogenetics. Knowledge of the life cycles for the ancestral pseudotuberculosis and derivative plague microbes as well as related unique environmental features allows to create a reliable ecological model for the plague microbe evolution to be further used for assessing patterns of molecular variability and building proper molecular model that might be accepted for MG-reconstruction of plague microbe history. According to the ecological model, the species Y. pestis was formed in a tritopic manner (almost) simultaneously from FESLF clones (populations) in the three geographical populations of the Mongolian marmot-tarbagan (Marmota sibirica) and the flea Oropsylla silantiewi parasitizing on it. The inducer of speciation was coupled to the last maximum (Sartan) cooling in Central Asia occurred 2215 thousand years ago. Soil cooling and deep freezing resulted in altered behavior of the marmot flea larvae with emergence of facultative hematophagy, which, in turn, led to a unique traumatic (compared to routine alimentary) infection route of sleeping marmots with FESLF and, as a result, a unique way of Y. pestis speciation. The molecular model should predict a Y. pestis peripatric tritope speciation, existing numerous parallelisms in intraspecific variability associated with tritope speciation, and the quantum principle of speciation in the highly variable heterothermic (heteroimmune) stressful marmot-flea (Marmota sibirica Oropsylla silantiewi) host-vector environment involving stress-induced mutagenesis. Such molecular model of evolution may be useful for improving molecular methodology of phylogenetic constructions for a wide range of parasitic microorganisms.

Mongolian Marmot (<i>Marmota sibirica</i>) Ecosystem Engineering Effects on Herpetofauna

The Mongolian marmot (Marmota sibirica) is a relatively large-bodied, social rodent that lives in colonies across the Mongolian steppes and adjacent parts of China and Russia. Marmots serve as ecosystem engineers that display multiple functions on the steppe environments they inhabit. Mongolian marmots experienced a 75% decline across Mongolia in the 1990s that led to their listing as endangered globally. The decline of marmots likely affected other species given their importance to the ecosystems they inhabit. To examine the role of marmots on herpetofauna, we established drift fence arrays with associated pitfall and funnel traps on active marmot colonies, inactive colonies, and control sites in the forest-steppe and semi-desert zones of Mongolia. In total, we identified 555 individuals representing 5 species of reptiles in Ikh Nart Nature Reserve (semi-desert) from 2010 – 2011 and 22 individuals of 3 species of reptiles and one amphibian species in Hustai National Park (forest-steppe) in 2014 and 2016. We found significantly higher species abundance and some diversity indices on active and inactive colonies compared to control sites in Hustai. Vegetation height and cover significantly affected the abundance and species richness of reptiles in Ikh Nart. In Ikh Nart, we found that under conditions of higher vegetation cover and height, reptiles were distributed more widely across the landscape, but with lower vegetation cover and height, reptiles associated more strongly with marmot burrows. Burrows likely provide shelter from extreme climatic conditions and refugia from predation. Our research provides insights into how marmots create important habitats for associated fauna. This and similar experimental approaches will allow us to better understand the biodiversity patterns in and around marmot burrows.

Polytopic Speciation of the Plague Microbe Yersinia pestis as the Cause of the Trichotomy in the Geographic Populations of the Mongolian Tarbagan Marmot (Marmota sibirica)

Polytopic Speciation of the Plague Microbe Yersinia pestis as the Cause of the Trichotomy in the Geographic Populations of the Mongolian Tarbagan Marmot (Marmota sibirica)

Climate Changes in Central Asia as a Prerequisite and Trigger of Plague Microbe (Yersinia pestis) Speciation.

Two physical and climatic factors that were distant and recent prerequisites and a transformation trigger for a clone of the ancestral pseudotuberculous microbe Yersinia pseudotuberculosis O:1b (the causative agent of the Far East scarlet-like fever (FESLF)) into a population of the plague microbe derivative Y. pestis are considered. One remote prerequisite was the aridification of the Central Asian landscapes in the second half of the Cenozoic period and the formation of the Gobi Arid Zone. The arid conditions of Central Asia determined the formation of adaptive species-specific protective behavior in the Tarbagan marmot (Marmota sibirica) when installing the plug of a wintering hole, which later contributed to the massive infection of the animals with FESLF by the aberrant (traumatic, not alimentary) method during hibernation. A recent prerequisite and a real trigger of Y. pestis speciation was the onset of the last maximum (Sartan) ice age in Central Asia at the turn of the Pleistocene and Holocene, 22 000–15 000 years ago. Freezing of the cooling burrows of the Tarbagan marmot caused a behavioral shift in the larval population of the marmot flea Oropsylla silantiewi and the transition to the cold winter–spring months of the year from saprophagy in the nesting litter to hematophagy on the bodies of sleeping animals. Larval scarifications in the oral cavity of sleeping marmots have become the entrance gate for a unique traumatic FESLF infection. The constellation of climatic changes, the heterothermal (and, accordingly, heteroimmune) condition of the family groups of sleeping marmots, and the year-round propagation of marmot fleas in wintering burrows, combined with behavioral shifts in marmots and fleas caused by climatic changes, led to the formation of conditions in the parasitic system M. sibirica–O. silantiewi in which the transformation of the FESLF microbe into the causative agent of the plague occurred according to peripatric speciation. Thus, the climatic changes that happened at different times in the Cenozoic initially led to a shift in behavior of the Tarbagan marmot and, subsequently, to a shift in the behavior of the fleas parasitizing it. Ultimately, the change in the behavior of marmots and fleas caused the transition of the clone(s) of the FESLF causative agent into a new ecological niche and adaptive zone, as well as the transformation into a population(s) of the plague microbe.

Ecosystem engineering influence of Mongolian marmots (Marmota sibirica) on small mammal communities in Mongolia

Mongolian marmots (Marmota sibirica) live in colonies that consist of numerous burrows and are considered ecosystem engineers. Although once a common steppe species, marmots are now endangered due to overharvesting, which has led to concerns over the impacts of their loss on other species. The decline of marmots likely affected other species given their importance to the ecosystems they inhabit. To examine the role of marmots on small mammal, we established Sherman traps and drift fence arrays with associated pitfall and funnel traps on active marmot colonies, inactive colonies, and control sites in the forest-steppe and semi-desert zones of Mongolia. Overall, we identified 385 individuals representing 11 species of rodents and 1 species of bat in Ikh Nart and 149 individuals representing 2 species of rodents and 1 species of insectivore from Hustai. We found mixed results between diversity indices and abundance of small mammals on treatment and control sites, complicating the picture. During periods of greater precipitation and resulting higher vegetation cover, species abundance and the Shannon-Wiener, Simpson's, and evenness indices all changed significantly, suggesting that the effect of marmots on other species varies based on environmental conditions.

Mongolian marmot burrow influences an occupancy of Isabelline wheatear

Mongolian marmot burrow influences an occupancy of Isabelline wheatear

Analysis on prevalence and epidemic risk of animal plague in different ecological plague foci in Inner Mongolia Autonomous Region

The risk of plague epidemics and relapse of various types of plague foci persists in Inner Mongolia Autonomous Region. For Marmota sibirica plague foci, the animal plague has not been found but antibody has been detected positive. Nowadays, Marmota sibirica has been increasing in population and distribution in China. In bordering countries Mongolia and Russia, the animal plague has been continuously prevalent. For Spermophilus dauricus plague foci, the animal plague has been taken place now and then. Compared to the above foci, the animal plague is most prevalent in Meriones unguiculatus plague foci and frequently spread to humans. Due to higher strain virulence and historical disaster in Marmota sibirica plague foci and Spermophilus dauricus plague foci, plague prevention and control should be strengthened on these foci. In addition to routine surveillance, epidemic dynamics need to be further monitored in these two foci, in order to prevent their relapse and spread to humans.

Effect of Ecological Factors on the Abundance of the Tarbagan (Marmota sibirica, Rodentia, Sciuridae) in Southwestern Transbaikalia

Effect of Ecological Factors on the Abundance of the Tarbagan (Marmota sibirica, Rodentia, Sciuridae) in Southwestern Transbaikalia

Distribution and Characteristics of Human Plague Cases and Yersinia pestis Isolates from 4 Marmota Plague Foci, China, 1950-2019.

We analyzed epidemiologic characteristics and distribution of 1,067 human plague cases and 5,958 Yersinia pestis isolates collected from humans, host animals, and insect vectors during 1950–2019 in 4 Marmota plague foci in China. The case-fatality rate for plague in humans was 68.88%; the overall trend slowly decreased over time but fluctuated greatly. Most human cases (98.31%) and isolates (82.06%) identified from any source were from the Marmota himalayana plague focus. The tendency among human cases could be divided into 3 stages: 1950–1969, 1970–2003, and 2004–2019. The Marmota sibirica plague focus has not had identified human cases nor isolates since 1926. However, in the other 3 foci, Y. pestis continues to circulate among animal hosts; ecologic factors might affect local Y. pestis activity. Marmota plague foci are active in China, and the epidemic boundary is constantly expanding, posing a potential threat to domestic and global public health.

Ecosystem engineering by endangered Mongolian marmots supports darkling beetles

Mongolian marmots (Marmota sibirica) live in colonies that consist of numerous burrows and are considered ecosystem engineers. Although once a common steppe species, marmots are now endangered due to overharvesting, which has led to concerns over the impacts of their loss on other species. We examined the role of marmots and other landscape characteristics on the distribution of the darkling beetle, Blaps rugosa, a detritivore that serves important functions in steppe ecosystems. We surveyed 130 sites for B. rugosa in Hustai National Park, Mongolia, and used a model selection approach to evaluate the effect of marmot burrows on occupancy probability. We detected B. rugosa in 22% of surveys (87/390) and at 45% of sites. Our top model indicated that occupancy was strongly influenced by burrows. Estimated occupancy was 0.91 at burrow sites and 0.39 at non-burrow sites. Detection was a function of temperature and highest around 24.5 °C. Our results suggest that the loss of marmots will negatively affect the distribution of B. rugosa and the ecosystem processes they support. Our study provides one of the few examples of the role of marmots in influencing invertebrates, and supports the notion of marmots as a keystone species.

Assessing wildlife biodiversity using camera trap data on the Mongolian marmot (Marmota sibirica) colonies

The Mongolian marmot (Marmota sibirica) is a relatively large-bodied, social rodent that lives in colonies across the Mongolian steppes and parts of China and Russia. Marmots serve as ecosystem engineers that display multiple functions on the steppe environments they inhabit. Mongolian marmots experienced a >75% decline across Mongolia in the 1990s that led their listing as endangered globally. The decline of marmots likely affected other species given their importance to the ecosystems. To examine the role of marmots on vertebrate species, we set camera traps on and off marmot colony sites in the forest-steppe, steppe, and semi-desert zones of Mongolia. In total, we recorded 39 vertebrate species within 3 study areas, including 19 species in 2012 in Ikh Nart NR; 21 in 2016 in Hustai NP; and 27 in the Halzan region of Sukhbaatar in 2019. Species abundance and some diversity indices were significantly higher on colonies compared to off colony sites. Our research provides insights into how marmots create important habitats for associated fauna and demonstrates that this engineering species plays an irreplaceable role in this ecosystem. We hope that this and similar experimental approaches will allow us to better understand the biodiversity patterns in and around marmot burrows.

Genomogenesis of the Plague Bacteria Yersinia pestis as a Process of Mosaic Evolution

The guiding methodological principle of the modern molecular genetic (MG) approach to the problem of speciation of the plague bacteria Yersinia pestis is the saltationist paradigm of horizontal gene transfer. The main speciation events include the insertion of two virulence plasmids specific to Y. pestis, pFra and pPst, into the genome of ancestral psychrophilic saprozoonotic pseudotuberculosis bacteria Y. pseudotuberculosis O:1b, as well as inactivation/deletion of genes that have lost their functions. An alternative ecological approach suggests the “Darwinian” mechanism of the plague bacterium genome formation in the temperature-continuous (5–37°C) environment, i.e., the Tarbagan marmot–marmot flea (Marmota sibirica–Oropsylla silantiewi) parasitic system, which demonstrates intermediate properties between the habitats of progenitor and derivative species. In accordance with the ecological scenario of the plague origin, the evolutionary fate of 18 well-studied plague bacterium genes and gene structures was interpreted. It was demonstrated that gradual transformation of the genome of the pseudotuberculosis bacterium into the genome of plague causative agent proceeded according to the principle of mosaic evolution and corresponded to three types of adaptation, i.e., inadaptation, pre-adaptation and neo-adaptation. The prospects for further development of the theory of plague origin are thought to be in the synthesis of MG and ecological approaches.

Ecosystem Engineering Effects of Mongolian Marmots (Marmota sibirica) on Terrestrial Arthropod Communities

The Mongolian marmot (Marmota sibirica) is a large, endangered rodent species that ranges across the steppe regions of Mongolia, and parts of China and Russia. Marmot lives colonially and creates extensive burrow systems that change the soil nutrient profiles and influence plant and animal community composition and productivity. We examined the role of marmots on the diversity and abundance of ground-dwelling and flying insects. We hypothesize that the arthropod communities differ between marmot colonies and surrounding grasslands in diversity and abundance. We trapped 4765 individuals of arthropods representing 178 species of insects and 12 families of spiders. Marmot colony sites differed significantly from off colony sites by communities of ground-dwelling and flying insects. Our findings indicate that abundance and species richness of arthropods are largely associated with marmot burrows, which might be a reason for increased habitat heterogeneity, such as bare ground, specific vegetation structure, and thermoregulatory site by ecosystem engineering. Our results demonstrate that the marmots are keystone species in arid ecosystems, and have complementary, additive effects on steppe arthropod communities.

Results of Epizootiological Survey along the Border Areas of Kharkhira-Turgensky Natural Plague Focus between Russia and Mongolia in 2019

Objective of the study was to assess the current epizootic settings along the border part of KharkhiraTurgensky natural plague focus betweenRussia andMongolia.Materials and methods. Epizootiological survey covered 2715.5 km2. 213 samples of field material were tested (90 specimens of mammals, 102 specimens of ectoparasites, 17 samples of leftover food of predatory birds and dry skeletal remnants of marmots, 4 regurgitates of birds of prey). Laboratory works were carried out in “Microbiological laboratory for express diagnostics” mounted on the platform of the minibus “GAZelle”. Tests of field material were performed using immune-chromatographic (IC) assay and polymerase chain reaction (PCR). PCR and IC positive samples were further investigated applying bacteriological method. Epizootiological surveyed deployed GIS instruments. All the results obtained were plotted on the electronic maps using QGIS 2.18.26 software.Results and discussion. Capsular antigen (F1) of Yersinia pestis was detected in three (1.4 %) studied samples (n=213), DNA of plague microbe – in eight samples (3.7 %). Bacteriological investigation of positive samples revealed one sample (leftover food of predatory birds – Mongolian marmot) from which plague agent culture was isolated. The culture belonged to Y. pestis of the main subspecies. Geographical positioning of the epizootiological survey sites was conducted, as well as positive findings of immunological and molecular-genetic assays. Results of epizootiological survey are indicative of active phase of plague agent circulation (main subspecies) in Kharkhira-Turgensky natural focus in Mongolia.

Prospects for the Synthesis of Ecological and Molecular-Genetic Approaches to the Problem of the Speciation of the Plague Microbe Yersinia pestis

This review discusses two approaches to the problem of the recent origin of the plague microbe Yersinia pestis molecular-genetic (MG) and ecological. The MG approach proclaims uneven speciation (saltation), and horizontal gene transfer is considered to be the main factor of speciation. The ecological scenario of “Darwinian” speciation includes three types of genetic structures in the genome of Y. pestis: (1) a nonadaptive structure, which lost functions of the ancestral microbe Y. pseudotuberculosis O:1b during speciation, (2) a preadaptive structure, which supported transition into a new environment, and (3) a (neo)adaptive structure, which formed endogenously during speciation in the transitional environment—the host–parasite system of the Mongolian marmot–flea (Marmota sibirica–Oropsylla silantiewi). The ecological approach can integrate MG data and adequately interpret them in accordance with the postulates of the modern synthetic theory of evolution. The prospects for the determination of the mechanisms of the speciation process can be seen in the synthesis of ecological and MG approaches.

Pneumonic Plagues, Environmental Changes, and the International Fur Trade: The Retreat of Tarbagan Marmots from Northwest Manchuria, 1900s-30s

Pneumonic Plagues, Environmental Changes, and the International Fur Trade: The Retreat of Tarbagan Marmots from Northwest Manchuria, 1900s-30s

Host animal surveillance in plague focus of Marmota sibirica in Hulunbeir plateau, 2009–2018

ObjectiveTo analyze host animal surveillance results in plague focus of Marmota sibirica from 2009 2018 in inner Mongolia, and provide evidence for the prevention and control of plague. MethodsThe surveillance was conducted according to National Plague Surveillance Protocol”and enforcement regulation. The plague surveillance results reported by Hulunbeir City Center for Disease Prevention and Control and the data reported through the Information Management System of Plague Prevention and Control in surveillance area from 2009 2018 were collected for descriptive epidemiological analysis and rank-sum test. ResultsFrom 2009 2018, a total of 6 535 rodents of 11 species, 10 genera, 5 families and 2 orders were captured, i.e. Spermophilus dauricus, Marmota sibirica, Phodopus sungarus, Allactaga sibirica, Meriones unguiculatus, Cricetulus barabensis, Lasiopodomys brandtii, Mus musculus, Ochotona dauurica, Microtus gregalis and Rattus norvegicus. The average density of the main host Marmota sibirica was 0.07/km2, ranging from 0.16/km2 0.02/km2. The number of Marmota sibiricas observed or captured in Chenbaerhu banner accounted for 95.80% of the total; The average density of Spermophilus dauricus was 0.50/km2 and the difference in its density among different areas was significant (χ2＝10.380, P＝0.006). The flea infection rate was 29.61% and the body flea index was 1.06. Eleven plague positive serum samples of Spermophilus dauricus were detected in Xinbaerhuyou banner of Manzhouli with highest titer of 1∶1 280. ConclusionThe overall density of Marmota sibiricas in Hulunbuir is kept at a low level. Spermophilus dauricus has become the predominant rodent specie which carries high titer plague antibody, suggesting that there is an epidemic of animal plague and it is necessary strengthen the surveillance and control of animal and human plague.

Origin of the Plague: Prospects of Ecological-Molecular-Genetic Synthesis

Plague, which is infamous for three devastating pandemics, remains to this day one of the most dangerous human diseases. Its pathogen, the microbe Yersinia pestis, is a priority agent in the arsenal of possible bacteriological weapons, which requires increased attention to the preventive development of systems of biological (bacteriological) security. Deep knowledge of the natural processes that caused the emergence of the causative agent of plague in nature might contribute to it. In the problem of the origin of Y. pestis, there are currently two alternative approaches, molecular-genetic (MG) and ecological. MG data led to the innovative idea of the saltational transformation of a clone of the ancestral psychrophilic saprozoobiont pseudotuberculosis microbe Y. pseudotuberculosis O:1b into a population of the plague pathogen Y. pestis by means of horizontal transfer of two plague-specific virulence plasmids pFra and pPst from the external environment or from other bacteria and inactivation/deletion of genes that lost their functions in a fundamentally new habitat, the vole (Microtinae) populations in Asia. The ecological scenario is based on the Darwinian idea of the adaptogenesis of the plague microbe with the rapid “quantum” formation of its properties in the marmot- flea (Marmota sibirica and Oropsylla silantiewi) parasitic system under the conditions of the Central Asia psychroarid climate at the turn of the Pleistocene and Holocene periods. Three important factors of quantum speciation of the plague microbe were identified: marmot heterothermy during hibernation, an oxidative burst of macrophages in the body of repeatedly awakening hibernating marmots, and stress-induced muta-genesis of the evolving microbe due to the oxidative burst of macrophages. This paper argues the principle of complementarity between the environmental and MG approaches. The prospect of solving the problem of quantum speciation of the causative agent of plague and the development of tools and methods for treating and preventing this disease is seen in the synthesis of the ecological and MG approaches.

Population Status of Tarbagan (Marmota sibirica Radde, 1862) in the Daursky State Nature Biosphere Reserve and Dzeren Valley Federal Nature Refuge

Field studies on the distribution and population size of tarbagan (Mongolian marmot) were carried out in 2010–2017 in districts of Zabaikal’skii krai bordering Mongolia and China. The study area constitutes parts of federal-level, strictly protected areas: Daursky State Nature Biosphere Reserve and Dzeren Valley Federal Nature Refuge. It is shown that the tarbagan population in the study area has reached more than 2000 families by 2017. The most active population restoration is observed in habitats historically characterized by the maximum tarbagan population: the Nerchinskii Ridge near the Mongolian border. Engineering structures at the border and the special frontier regime contributed to the preservation of the original marmot settlements. Marmot migration from Mongolia no longer plays an important role in the maintenance of frontier marmot populations in the studied section of the Russian–Mongolian border.