Where vegetation communities adjacent to talus bases forefields were grazed, mean distance from the talus borders to the closest fresh Predictors of current and longer-term patterns of abundance of American pikas Ochotona princeps across a leading-edge protected area. American pikas Ochotona princeps have been heralded as indicators of montane-mammal response to contemporary climate change.
Pikas no longer occupy the driest and lowest-elevation sites in numerous parts of their geographic range. Research and monitoring efforts on pikas across the western USA have collectively shown the nuance and complexity with which climate will often act on species in diverse topographic and climatic contexts. However, to date no studies have investigated habitat, distribution, and abundance of pikas across hundreds of sites within a remote wilderness area.
Additionally, relatively little is known about whether climate acts most strongly on pikas through direct or indirect e. We identified apparently pika -suitable habitat patches with binoculars in situ , and surveyed of them for pika signs. Earlier Julian date and time of day of the survey i. We recommend that wildlife monitoring account for this seasonal and diel variation when surveying pikas. Broad-scale information on status and abundance determinants of montane mammals, especially. Directory of Open Access Journals Sweden.
Full Text Available Some of the most compelling examples of ecological responses to climate change are elevational range shifts of individual species, which have been observed throughout the world. A growing body of evidence, however, suggests substantial mediation of simple range shifts due to climate change by other limiting factors. Understanding limiting factors for a species within different contexts, therefore, is critical for predicting responses to climate change. The American pika Ochotona princeps is an ideal species for investigating distributions in relation to climate because of their unusual and well-understood natural history as well as observed shifts to higher elevation in parts of their range.
We tested three hypotheses for the climatic or habitat characteristics that may limit pika presence and abundance: We performed these tests using an index of pika abundance gathered in a region where environmental influences on pika distribution have not been well-characterized. Pika scat density was highest at mid-elevations and increased linearly with forage availability in both ranges. Our results provide support for both the forage availability and winter snowpack hypotheses.
Especially in montane systems, considering the context-dependent nature of climate effects across regions and elevations as well as interactions between climatic and other critical habitat characteristics, will be essential for predicting future species distributions. Climate tolerances and habitat requirements jointly shape the elevational distribution of the American Pika Ochotona princeps , with implications for climate change effects.
Some of the most compelling examples of ecological responses to climate change are elevational range shifts of individual species, which have been observed throughout the world. Discovery of new Ohbayashinema spp. Heligmosomoidea in Ochotona princeps and Ochotona cansus Lagomorpha: Ochotonidae from western North America and Central Asia, with considerations of historical biogeography.
Three new species of Ohbayashinema Nematoda, Heligmosomoidea are described from localities in western North America and central Asia. Two of these species, Ohbayashinema nearctica n. Ohbayashinema nearctica is differentiated from the 5 known species of the genus parasitic in Ochotonidae from the Old World by very long spicules and an oblique axis of orientation for the ridges composing the synlophe.
Ohbayashinema aspeira, described only from females, is similar to Oh. It is mainly differentiated by an uncoiled anterior extremity and by near equal dimensions of the vestibule and the uterus. The third species, Ohbayashinema patriciae n.
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It is similar to Ohbayashinema erbaevae parasitic in Ochotona dauurica from Buriatia and Ohbayashinema ochotoni in Ochotona macrotis from Nepal, based on the length of the spicules and the ratio of spicule length to body length. It differs from the former species by possessing a smaller number of cuticular ridges and in the comparative length of the vestibule and infundibulum. Species of Ohbayashinema appear to be host-specific among the Ochotonidae but had not been previously reported in pikas from the Nearctic.
Although much remains to be demonstrated about the diversity for helminths in pikas , it is apparent that factors associated with the assembly and structure of parasite faunas have been complex, involving episodic processes for geographic and host colonization along with coevolutionary mechanisms. Understanding the historical factors, particularly climate.
Sacral Variability in Tailless Species: Homo sapiens and Ochotona princeps. Homo sapiens is variable in number of sacral vertebrae, and this variability can lead to obstetrical complication. This study uses the comparative method to test the hypothesis that sacral variability in H. Three species of lagomorphs are studied: Results show that O. Homeotic transformation best explains the results. Caudal and cranial shift among presacral vertebrae increases or decreases this propensity, respectively.
Increase in number of sacral vertebrae in H.
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Functional-trait ecology of the plateau pika Ochotona curzoniae Hodgson, in the Qinghai-Tibetan Plateau ecosystem. Understanding a species' functional traits allows for a directed and productive perspective on the role a species plays in nature, thus its relative importance to conservation planning. The functional trait ecology of the plateau pika Ochotona curzoniae Hodgson, is examined to better understand the resilience and sustainability of the high alpine grasslands of the Qinghai-Tibetan Plateau QTP.
The key functional traits of plateau pikas are their abundance and behavior of digging extensive burrow systems.
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Plateau pikas have been poisoned over a significant part of their original geographic distribution across the QTP, allowing comparison of ecological communities with and without pikas. Nearly all mammalian and avian carnivores, most of which are obligate predators on pikas , have been lost in regions where pikas have been poisoned. Most endemic birds on the QTP nest in pika burrows; when pikas are poisoned, burrows collapse, and these birds are greatly reduced in number. Due to the biopedturbation resulting from their burrows, regional plant species richness is higher in areas with pikas than without.
The presence of pika burrows allows higher rates of infiltration during heavy monsoon rains compared to poisoned areas, possibly mitigating runoff and the potential for serious downslope erosion and flooding. Thus the functional traits of plateau pikas enhance native biodiversity and other important ecosystem functions; these traits are irreplaceable. As plateau pikas are not natural colonizers, active re-introduction programs are needed to restore pikas to areas from which they have been poisoned to restore the important functional ecological traits of pikas.
This article is protected by copyright. Effectiveness of 10 polymorphic microsatellite markers for parentage and pedigree analysis in plateau pika Ochotona curzoniae. A set of 10 polymorphic microsatellite loci has been developed earlier. Its reliability for parentage assignment has been tested in a plateau pika population. Two family groups with a known pedigree were used to validate the power of this set of markers. Results The error in parentage assignment using a combination of these 10 loci was very low as indicated by their power of discrimination 0.
Conclusion All the offspring of a family could be assigned to their biological mother; and their father or relatives could also be identified. This set of markers therefore provides a powerful and efficient tool for parentage assignment and other population analyses in the plateau pika. Forage selection by Royle's pika Ochotona roylei in the western Himalaya, India. Forage selection decisions of herbivores are often complex and dynamic; they are modulated by multiple cues, such as quality, accessibility and abundance of forage plants.
To advance the understanding of plant-herbivore interactions, we explored foraging behavior of the alpine lagomorph Royle's pika Ochotona roylei in Kedarnath Wildlife Sanctuary, India. Pika bite counts on food plants were recorded through focal sampling in three permanently marked plots. Food plant abundance was recorded by traditional quadrat procedures; forage selection was estimated with Jacob's selection index.
Multiple food-choice experiments were conducted to determine whether forage selection criteria would change with variation in food plant composition. We also analyzed leaf morphology and nutrient content in both major food plants and abundantly available non-food plants. Linear regression models were used to test competing hypotheses in order to identify factors governing forage selection. Royle's pika fed primarily on 17 plant species and each forage selection decision was positively modulated by leaf area and negatively modulated by contents of avoided substances neutral detergent fiber, acid detergent fiber, acid detergent lignin and tannin in food plants.
The forage selection criteria did not differ between field and laboratory experiments. The parameter estimates of best fit models indicate that the influence of leaf size or amount of avoided substance on pika forage selection was modulated by the magnitude of predation risk. Full Text Available Testis-specific lactate dehydrogenase LDH-C4 is one of the lactate dehydrogenase LDH isozymes that catalyze the terminal reaction of pyruvate to lactate in the glycolytic pathway.
LDH-C4 in mammals was previously thought to be expressed only in spermatozoa and testis and not in other tissues. Plateau pika Ochotona curzoniae belongs to the genus Ochotona of the Ochotonidea family. It is a hypoxia-tolerant species living in remote mountain areas at altitudes of — m above sea level on the Qinghai-Tibet Plateau. Surprisingly, Ldh-c is expressed not only in its testis and sperm, but also in somatic tissues of plateau pika. To shed light on the function of LDH-C4 in somatic cells, Ldh-a, Ldh-b, and Ldh-c of plateau pika were subcloned into bacterial expression vectors.
The enzymatic kinetics properties of these enzymes were studied by Lineweaver-Burk double-reciprocal plots. At relatively high concentrations of lactate, the inhibition constant Ki of the LDH isoenzymes varied: In light of the enzymatic kinetics properties, we suggest that the plateau pika can reduce reliance on oxygen supply and enhance its adaptation to the hypoxic environments due to increased anaerobic glycolysis by LDH-C4.
Food plant species were identified by visual observation and quantified by a standard quadrat method. The highest relative abundance was observed at man-made walls and surroundings in the alpine zone and on broken slopes in the sub-alpine one, whereas alpine meadows showed the lowest abundance. A total of 26 plant species were found to be consumed by pikas. The proportion of forage plants was the highest Rocky areas probably offer both nest-sites and temporary refuges to escape from predators. Riassunto Abbondanza relativa del pica di Royle Ochotona roylei lungo un gradiente altitudinale in Uttarakhand, Himalaya occidentale.
Sono stati identificate tre fasce altitudinali e 10 habitat complessivi. Genetic diversity in Echinococcus shiquicus from the plateau pika Ochotona curzoniae in Darlag County, Qinghai, China. The metacestode of Echinococcus shiquicus has been recorded previously in the lung and liver of its intermediate host, the plateau pika Ochotona curzoniae , but there is limited information regarding other organ sites. There is also limited evidence of intra-specific genetic variation within E. A PCR-amplified mitochondrial mt nad1 gene fragment approximately bp in size , with unique EcoRI and SspI restriction sites, was used to distinguish cysts or cyst-like lesions of E.
Then, the complete mt nad1 and cox1 genes for the E. Phylogenetic tree and haplotype network analyses for the isolates were then generated based on a concatenated dataset of the nad1 and cox1 genes using the neighbour-joining NJ method and TCS1. Nineteen of eighty trapped pikas were found to harbor cysts 71 in total when dissected at the survey site. Seventeen animals had cysts fertile present only in the lungs, one animal had fertile cysts in the lungs and spleen, and one individual had an infertile kidney cyst.
Restriction endonuclease analysis of a fragment of the nad1 gene indicated all the cysts were due to E. Genetic diversity analysis revealed that the nad1 and cox1 genes varied by 0. Haplotype network analysis of the concatenated nad1 and cox1 sequences of the isolates showed they were classified into at least 6 haplotypes, and different haplotype percentages ranged from 4.
Although, high haplotype diversity was evident in the study area, the complete nad1 and cox1 gene sequences obtained indicated that all samples represented isolates of E. The study has also provided a new PCR-restriction endonuclease-based method to rapidly distinguish E. Radiocarbon dating of American pika fecal pellets provides insights into population extirpations and climate refugia.
The American pika Ochotona princeps has become a species of concern for its sensitivity to warm temperatures and potential vulnerability to global warming. We explored the value of radiocarbon dating of fecal pellets to address questions of population persistence and timing of site extirpation.
Carbon was extracted from pellets collected at Ruminants are the natural reservoir of STEC. A total of pika samples, including intestinal contents samples, fecal samples, and intestinal contents samples, were collected from May to August in the years , , and , respectively. Thirteen different O serogroups and 14 serotypes were identified. One stx 1 subtype stx 1a and three stx 2 subtypes stx 2a, stx 2b, and stx 2d were present in the STEC isolates. Adherence-associated genes iha and saa were, respectively, present in Twenty antibiotics were active against all the STEC isolates; all strains were resistant to penicillin G, and some to cephalothin or streptomycin.
The 22 STEC isolates were divided into 16 pulsed-field gel electrophoresis patterns and 12 sequence types. Based on the serotypes, virulence gene profiles and multi-locus sequence typing MLST analysis, the majority of these pika STECs may pose a low public health risk. The expression of Ldh-c in the skeletal muscle of plateau pika Ochotona curzoniae enhances adaptation to a hypoxic environment.
Full Text Available The plateau pika Ochotona curzoniae is a species of sprint-running alpine animals in the Qinghai-Tibet Plateau, which is a harsh highland hypoxic environment. Ldh-c is expressed in the testis, sperm and somatic tissues of plateau pika. To reveal the role and physiological mechanisms of sperm-specific lactate dehydrogenase LDH-C4, in plateau pika to adapt to hypoxic environment, an adenoviral line of pMultiRNAi-Ldhc was constructed and injected into the bilateral biceps femoris of the hind legs.
Our results showed that after Ldh-c was silenced, the sprint-running ability swimming time of the plateau pikas was significant decreased, and the total LDH activities and ATP levels were reduced by Our results indicated that expression of Ldh-c in the skeletal muscle of plateau pika increased anaerobic glycolysis and enhanced adaptation to highland hypoxic environments.
The first report of Cryptosporidium spp. Cryptosporidium is one of the most important genera of intestinal zoonotic pathogens, which can infect various hosts and cause diarrhoea. There is little available information about the molecular characterisation and epidemiological prevalence of Cryptosporidium spp. Positive samples were successfully sequenced, and the following Cryptosporidium species were found: This is the first report of Cryptosporidium infections in M.
The results suggest the possibility of Cryptosporidium species transmission among these two hosts, the environment, other animals and humans and provide useful molecular epidemiological data for the prevention and control of Cryptosporidium infections in wild animals and the surrounding environments. The results of the present study indicate the existence of Cryptosporidium species infections that have potential public health significance. This is the first report of Cryptosporidium multi-species infections in these animal hosts.
American pika in a low-elevation lava landscape: In , the American pika Ochotona princeps fenisex was denied federal protection based on limited evidence of persistence in low-elevation environments. Studies in nonalpine areas have been limited to relatively few environments, and it is unclear whether patterns observed elsewhere e. This study was designed to establish pika presence in a new location, determine distribution within the surveyed area, and evaluate influences of elevation, vegetation, lava complexity, and distance to habitat edge on pika site occupancy.
Field surveys were conducted at predetermined locations within lava flows via silent observation and active searching for pika sign. Site habitat characteristics were included as predictors of occupancy in multinomial regression models. Above and belowground temperatures were recorded at a subsample of pika detection sites. Seventy-four pika were detected outside survey plot boundaries.
Lava complexity was the strongest predictor of pika occurrence, where pika were up to seven times more likely to occur in the most complicated lava formations. Pika were two times more likely to occur with increasing elevation, although they were found at all elevations in the study area. This study expands the known distribution of the species and provides additional evidence for persistence in nonalpine habitats. Results partially support the predictive occupancy model developed for pika at Craters of the Moon National Monument, another lava environment.
Characteristics of the lava environment clearly influence pika site occupancy, but habitat variables reported as important in other studies were inconclusive here. Further work is needed to gain a better understanding of the species' current. Permanent and well supported museum collections provide a solid foundation for the process of systematics research through creation of an empirical record which validates our understanding of the biosphere.
We explore the role of museums in ongoing studies of the complex helminth fauna characterist Mechanistic variables can enhance predictive models of endotherm distributions: How climate constrains species' distributions through time and space is an important question in the context of conservation planning for climate change. Despite increasing awareness of the need to incorporate mechanism into species distribution models SDMs , mechanistic modeling of endotherm distributions remains limited in this literature. Using the American pika Ochotona princeps as an example, we present a framework whereby mechanism can be incorporated into endotherm SDMs.
Pika distribution has repeatedly been found to be constrained by warm temperatures, so we used Niche Mapper, a mechanistic heat-balance model, to convert macroclimate data to pika -specific surface activity time in summer across the western United States. We then explored the difference between using a macroclimate predictor summer temperature and using a mechanistic predictor predicted surface activity time in SDMs. Both approaches accurately predicted pika presences in current and past climate regimes.
Incorporating mechanism added value to the modeling by providing increased confidence in areas where different modeling approaches agreed and providing a range of outcomes in areas of disagreement. It also provided a more proximate variable relating animal distribution to climate, allowing investigations into how unique habitat characteristics and intraspecific phenotypic variation may allow pikas to exist in areas outside those predicted by generic SDMs. Only a small number of easily obtainable data are required to parameterize this mechanistic model for any endotherm, and its use can improve SDM predictions by explicitly modeling a widely applicable direct physiological effect.
The American pika under current, past, and future climates. Carbon was extracted from pellets collected at 43 locations in the western Great Basin, USA, including three known occupied sites and 40 sites of uncertain status at range margins or where previous studies indicated the species is vulnerable. We resolved calibrated dates with high precision within several years , most of which fell in the period of the mid-late 20th century bomb curve. The two-sided nature of the bomb curve renders far- and near-side dates of equal probability, which are separated by one to four decades.
We document methods for narrowing resolution to one age range, including stratigraphic analysis of vegetation collected from pika haypiles. No evidence was found for biases in atmospheric 14C levels due to fossil-derived or industrial CO2 contamination. Using combined evidence from field observations and radiocarbon dating, and the Bodie Mountains as an example, we propose a historical biogeographic scenario for pikas in minor Great Basin mountain ranges adjacent to major cordillera, wherein historical climate variability led to cycles of extirpation and recolonization during alternating cool and warm centuries.
Using this model to inform future dynamics for small ranges in biogeographic settings similar to the Bodie Mountains in California, extirpation of pikas appears highly likely under directional warming trends projected for the next century, even while populations in extensive cordillera e. Diet simplification selects for high gut microbial diversity and strong fermenting ability in high-altitude pikas. The gut microbiota in mammals plays a key role in host metabolism and adaptation. However, relatively little is known regarding to how the animals adapts to extreme environments through regulating gut microbial diversity and function.
Here, we investigated the diet, gut microbiota, short-chain fatty acid SCFA profiles, and cellulolytic activity from two common pika Ochotona spp. Despite a partial diet overlap, Plateau pikas harbored lower diet diversity than Daurian pikas. They harbored higher gut microbial diversity, total SCFA concentration, and cellulolytic activity than Daurian pikas.
Interestingly, cellulolytic activity was positively correlated with the gut microbial diversity and SCFAs. Gut microbial communities and SCFA profiles were segregated structurally between host species. PICRUSt metagenome predictions demonstrated that microbial genes involved in carbohydrate metabolism and energy metabolism were overrepresented in the gut microbiota of Plateau pikas. Our results demonstrate that Plateau pikas harbor a stronger fermenting ability for the plant-based diet than Daurian pikas via gut microbial fermentation.
The enhanced ability for utilization of plant-based diets in Plateau pikas may be partly a kind of microbiota adaptation for more energy requirements in cold and hypoxic high-altitude environments. Replicated landscape genetic and network analyses reveal wide variation in functional connectivity for American pikas. Landscape connectivity is essential for maintaining viable populations, particularly for species restricted to fragmented habitats or naturally arrayed in metapopulations and facing rapid climate change.
The importance of assessing both structural connectivity physical distribution of favorable habitat patches and functional connectivity how species move among habitat patches for managing such species is well understood. However, the degree to which functional connectivity for a species varies among landscapes, and the resulting implications for conservation, have rarely been assessed. We used a landscape genetics approach to evaluate resistance to gene flow and, thus, to determine how landscape and climate-related variables influence gene flow for American pikas Ochotona princeps in eight federally managed sites in the western United States.
We used empirically derived, individual-based landscape resistance models in conjunction with predictive occupancy models to generate patch-based network models describing functional landscape connectivity. Metareplication across landscapes enabled identification of limiting factors for dispersal that would not otherwise have been apparent. Despite the cool microclimates characteristic of pika habitat, south-facing aspects consistently represented higher resistance to movement, supporting the previous hypothesis that exposure to relatively high temperatures may limit dispersal in American pikas.
We found that other barriers to dispersal included areas with a high degree of topographic relief, such as cliffs and ravines, as well as streams and distances greater than km depending on the site. Using the empirically derived network models of habitat patch connectivity, we identified habitat patches that were likely disproportionately important for maintaining functional connectivity, areas in which habitat appeared fragmented, and locations that could be targeted for management actions to improve functional connectivity.
Functional evolution of leptin of Ochotona curzoniae in adaptive thermogenesis driven by cold environmental stress. Environmental stress can accelerate the directional selection and evolutionary rate of specific stress-response proteins to bring about new or altered functions, enhancing an organism's fitness to challenging environments. Plateau pika Ochotona curzoniae, an endemic and keystone species on Qinghai-Tibetan Plateau, is a high hypoxia and low temperature tolerant mammal with high resting metabolic rate and non-shivering thermogenesis to cope in this harsh plateau environment.
Leptin is a key hormone related to how these animals regulate energy homeostasis. Previous molecular evolutionary analysis helped to generate the hypothesis that adaptive evolution of plateau pika leptin may be driven by cold stress. To test the hypothesis, recombinant pika leptin was first purified.
Expression levels of genes regulating adaptive thermogenesis in brown adipose tissue and the hypothalamus are compared between pika leptin and human leptin treatment, suggesting that pika leptin has adaptively and functionally evolved. Our results show that pika leptin regulates energy homeostasis via reduced food intake and increased energy expenditure under both warm and cold conditions. Moreover, leptin treatment combined with cold stimulation has a significant synergistic effect on adaptive thermogenesis, more so than is observed with a single cold exposure or single leptin treatment.
These findings support the hypothesis that cold stress has driven the functional evolution of plateau pika leptin as an ecological adaptation to the Qinghai-Tibetan Plateau. Diazotrophic gut symbionts are considered to act as nitrogen providers for their hosts, as was shown for various termite species. Since our hypothesis was that pikas maintained a diazotrophic consortium in their gastrointestinal tract, we conducted the first investigation of microbial diversity in pika guts.
We obtained gut samples from animals of several Ochotona species, O.
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The age and gender of the animals were taken into consideration. We amplified bp long fragments of the nifH gene using the DNA extracted directly from the colon and cecum samples of pika 's gut, resolved them by DGGE, and performed phylogenetic reconstruction of 51 sequences obtained from excised bands. No significant difference was detected between the nitrogen-fixing gut inhabitants of different pika species.
NifH sequences fell into two clusters. Sequences from the second group were related to Treponema sp. We suggest that diazotrophic organisms from the second cluster are genuine endosymbionts of pikas and provide nitrogen for further synthesis processes thus allowing these animals not to be short of protein.
The burying and grazing effects of plateau pika on alpine grassland are small: On the one hand, pika is considered a keystone species. On the other hand, it is being poisoned. In this study, we investigated the direct effects, i. Altogether plots were set on four different types of alpine grassland in a semiarid basin on the QTP. We concluded that the direct burying and grazing effects of pika on alpine grassland were minor in this region.
The quadcopter is an efficient and economic tool for long-term repeated monitoring over large regions for further understanding the role of pika. There is considerable controversy about the effects of plateau pika Ochotona curzoniae, hereafter pika on alpine grassland on the Qinghai-Tibet Plateau QTP.
Genetic diversity and sex-bias dispersal of plateau pika in Tibetan plateau. Dispersal is an important aspect in organism's life history which could influence the rate and outcome of evolution of organism. Plateau pika is the keystone species in community of grasslands in Tibetan Plateau.
In this study, we combine genetic and field data to character the population genetic pattern and dispersal dynamics in plateau pika Ochotona curzoniae. Totally, 1, individual samples were collected, and 10 microsatellite loci were analyzed. Results revealed that plateau pika possessed high genetic diversity and inbreeding coefficient in a fine-scale population.
An effective sex-biased dispersal strategy is employed by plateau pika: Inbreeding avoiding was shown as the common driving force of dispersal, together with the other two factors, environment and resource. In addition, natal dispersal is female biased. More detailed genetic analyzes are needed to confirm the role of inbreeding avoidance and resource competition as ultimate cause of dispersal patterns in plateau pika.
Selle auks korraldati Riigikogu ja Eesti Lipu Seltsi poolt Toompea lossi aias riigi- ja rahvuslipu pidulik austamistseremoonia. Genetics, morphology and ecology reveal a cryptic pika lineage in the Sikkim Himalaya. This leads to uncertainty and species misidentification in the field. Phylogenetic analyses of such misidentified samples leads to taxonomic ambiguity. We sampled, measured, and acquired genetic data from pikas in the Sikkim Himalaya. Our analyses revealed a cryptic lineage, Ochotona sikimaria, previously reported as a subspecies of O.
The results support the elevation of this lineage to the species level, as it is genetically divergent from O. The Sikkim lineage diverged from its sister species' about 1. Our results add to the recent spate of cryptic diversity identified from the eastern Himalaya and highlight the need for further study within the Ochotonidae. Ochotonidae Go during the Pleistocene? New Evidence from Central Iberia. This paper reports the first find of pika remains in the Iberian Peninsula, at a site in central Spain. A fragmented mandible of Ochotona cf. This record establishes new limits for the genus geographic distribution during the Pleistocene, shifting the previous edge of its known range southwest by some km.
During those periods both the reduction of the forest cover and the emersion of large areas of the continental shelf due to the drop of the sea level probably provided these species a way to surpass this barrier. The pika mandible was found accompanying the remains of other small mammals adapted to cold climates, indicating the presence of steppe environments in central Iberia during the Late Pleistocene. Eesti vabariigi ja Kaitseliidu loomise A note on chromosomes of Pontellopsis herdmani and Pontella princeps Copepoda from the Laccadive sea. Pontellopsis herdmani and Pontella princeps Pontellidae, Calanoida, Copepoda showed a diploid number of 20 and a haploid number of 10 chromosomes during the spermatogonial metaphase and metaphase II stages.
The chromosomes were in the size range A novel rabies vaccine based-on toll-like receptor 3 TLR3 agonist PIKA adjuvant exhibiting excellent safety and efficacy in animal studies. Vaccination alone is not sufficiently effective to protect human from post-exposure rabies virus infection due to delayed generation of rabies virus neutralizing antibodies and weak cellular immunity.
Therefore, it is vital to develop safer and more efficacious vaccine against rabies. The efficacy and safety of PIKA rabies vaccine were evaluated. The results showed that PIKA rabies vaccine enhanced both humoral and cellular immunity. Thus, this study indicates that PIKA rabies vaccine is an effective and safe vaccine which has the potential to develop next-generation rabies vaccine and encourage the start of clinical studies.
Zhang, Yi [Yisheng Biopharma. Poisoning by the ingestion of seeds of the fruit of the "cotieira" Joannesia princeps. Full Text Available A year-old boy ingested the core of two seeds of a fruit of Joannesia princeps , a large tree sometimes found planted in sidewalks on streets in Brazilian towns. Four hours after the ingestion, he had several episodes of vomiting and diarrhea, but recovered spontaneously th same day. Poisoning by the ingestion of seeds of Joannesia princeps is possibly not rare, considering that the tree gives plenty of fruit and the seeds have an agreeable flavor, but is probably underestimated as mild cases are unlikely to be reported.
Ingestion by small children, that could lead to potentially more severe cases, is in part probably prevented by the hardness of the shells covering the seeds. Alelopatia de Joanesia princeps Vell. Os extratos aquosos de J. Full Text Available A plateau pika model with spatial cross-diffusion is investigated. By analyzing the corresponding characteristic equations, the local stability of an coexistence steady state is discussed when d21 is small enough.
A nonconstant positive solution bifurcates from the coexistent steady state by the Leray-Schauder degree theory. Numerical simulations are carried out to illustrate the main results. Too hot to trot? Varner, Johanna; Lambert, Mallory S. Wildfires are increasing in frequency and severity as a result of climate change in many ecosystems; however, effects of altered disturbance regimes on wildlife remain poorly quantified.
Here, we leverage an unexpected opportunity to investigate how fire affects the occupancy and abundance of a climate-sensitive habitat specialist, the American pika Ochotona princeps. We determine the effects of a fire on microclimates within talus and explore habitat factors promoting persistence and abundance in fire-affected habitat. Within 2 years, pikas were widely distributed throughout burned areas and did not appear to be physiologically stressed at severely burned sites. Furthermore, pika densities were better predicted by topographic variables known to affect this species than by metrics of fire severity.
This widespread distribution may reflect quick vegetation recovery and the fact that the fire did not alter the talus microclimates in the following years. Together, these results highlight the value of talus as a thermal refuge for small animals during and after fire. Modeling behavioral thermoregulation in a climate change sentinel. When possible, many species will shift in elevation or latitude in response to rising temperatures. However, before such shifts occur, individuals will first tolerate environmental change and then modify their behavior to maintain heat balance.
Behavioral thermoregulation allows animals a range of climatic tolerances and makes predicting geographic responses under future warming scenarios challenging. Because behavioral modification may reduce an individual's fecundity by, for example, limiting foraging time and thus caloric intake, we must consider the range of behavioral options available for thermoregulation to accurately predict climate change impacts on individual species.
To date, few studies have identified mechanistic links between an organism's daily activities and the need to thermoregulate. We used a biophysical model, Niche Mapper, to mechanistically model microclimate conditions and thermoregulatory behavior for a temperature-sensitive mammal, the American pika Ochotona princeps. Niche Mapper accurately simulated microclimate conditions, as well as empirical metabolic chamber data for a range of fur properties, animal sizes, and environmental parameters.
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Niche Mapper predicted pikas would be behaviorally constrained because of the need to thermoregulate during the hottest times of the day. We also showed that pikas at low elevations could receive energetic benefits by being smaller in size and maintaining summer pelage during longer stretches of the active season under a future warming scenario. We found that pikas were most active when temperatures were cooler, and at sites characterized by high elevations and north-facing slopes.
Comparativamente aos casos naturais, os caprinos intoxicados experimentalmente por M. The Department of Energy DOE is currently investing millions of dollars annually into various modeling and simulation tools for all aspects of nuclear energy. Thanks to the efforts of the DOE and outside collaborators, MOOSE currently contains a large set of physics modules, including phase-field, level set, heat conduction, tensor mechanics, Navier-Stokes, fracture and crack propagation via the extended finite-element method , flow in porous media, and others.
The heat conduction, tensor mechanics, and phase-field modules, in particular, are well-suited for snow science problems. Pika --an open-source MOOSE-based application--is capable of simulating both 3D, coupled nonlinear continuum heat transfer and large-deformation mechanics applications such as settlement and phase-field based micro-structure applications. Additionally, these types of problems may be coupled tightly in a single solve or across length and time scales using a loosely coupled Picard iteration approach.
In addition to the wide range of physics capabilities, MOOSE-based applications also inherit an extensible testing framework, graphical user interface, and documentation system; tools that allow MOOSE and other applications to adhere to nuclear software quality standards. The snow science community can learn from the nuclear industry and harness the existing effort to build simulation tools that are open, modular, and share a common framework.
In particular, MOOSE-based multiphysics solvers are inherently parallel, dimension agnostic, adaptive in time and space, fully coupled, and capable of interacting with other applications. The snow science community should build on existing tools to enable collaboration between researchers and practitioners throughout the world, and advance the. Adaptive population divergence and directional gene flow across steep elevational gradients in a climate-sensitive mammal. The ecological effects of climate change have been shown in most major taxonomic groups; however, the evolutionary consequences are less well-documented.
Adaptation to new climatic conditions offers a potential long-term mechanism for species to maintain viability in rapidly changing environments, but mammalian examples remain scarce. The American pika Ochotona princeps has been impacted by recent climate-associated extirpations and range-wide reductions in population sizes, establishing it as a sentinel mammalian species for climate change. To investigate evidence for local adaptation and reconstruct patterns of genomic diversity and gene flow across rapidly changing environments, we used a space-for-time design and restriction site-associated DNA sequencing to genotype American pikas along two steep elevational gradients at 30, SNPs and employed independent outlier detection methods that scanned for genotype-environment associations.
Additionally, we found evidence of directional gene flow primarily downslope from high-elevation populations, along with reduced gene flow at outlier loci. If this trend continues, elevational range contractions in American pikas will likely be from local extirpation rather than upward movement of low-elevation individuals; this, in turn, could limit the potential for adaptation within this landscape.
These findings are of particular relevance for future conservation and management of American pikas and other elevationally-restricted, thermally-sensitive species. Full Text Available Jaceosidin is a single compound from the Japanese mugwort Artemisia princeps , which is used as a food and a traditional medicinal herb. Although the anticancer properties of these extracts were recently demonstrated, the related mechanisms have not been characterised.
In addition, jaceosidin increased cleavage of caspase-9 and caspase-3 in OSCC cells, although caspase-8 was not detected. In further experiments, jaceosidin downregulated Akt phosphorylation and ectopic activation of Akt blocked the antiproliferative effects of jaceosidin. Finally, we showed that jaceosidin has no effects on HaCaT normal epithelial cell viability, indicating selective chemotherapeutic potential of jaceosidin and that tumour-specific downregulation of Akt increases apoptosis and inhibits growth in OSCC cells.
Many mammals create food stores to enhance overwinter survival in seasonal environments. Strategic arrangement of food within caches may facilitate the physical integrity of the cache or improve access to high-quality food to ensure that cached resources meet future nutritional demands. We used the American pika Ochotona princeps , a food-caching lagomorph, to evaluate variation in haypile cache structure i. Fifty-five percent of 62 haypiles contained at least 2 discrete layers of vegetation. Adults and juveniles layered haypiles in similar proportions. The probability of layering increased with haypile volume, but not haypile number per individual or nearby forage diversity.
Vegetation cached in layered haypiles was also higher in nitrogen compared to vegetation in unlayered piles. We found that American pikas frequently structured their food caches, structured caches were larger, and the cached vegetation in structured piles was of higher nutritional quality. Improving access to stable, high-quality vegetation in haypiles, a critical overwinter food resource, may allow individuals to better persist amidst harsh conditions.
Radioecology of natural systems. Final report, May 1, October 31, During the first five years of the program, investigations were focused on the accumulation of fallout radionuclides in a well-studied mule deer population in north-central Colorado. In , the scope of the program was enlarged to include studies on radionuclide behavior in mountain lake ecosystems, radiation effects on a shortgrass plains ecosystem, and the combined effects of radiation and intraspecific competition on the pika Ochotona princeps.
In , studies on the geochemistry of lead in an alpine lake and the foraging impact of grasshoppers were added to the diverse program. The summer of marked the beginning of the research program which was to dominate the effort for the duration of the contract, namely the behavior of plutonium in the terrestrial environs of the Rocky Flats plutonium facility near Denver, Colorado. This report is a general, qualitative summary of activities and major findings over the entire tenure of the program. What to eat in a warming world: Contemporary climate change affects nearly all biomes, causing shifts in animal distributions and resource availability.
Changes in resource selection may allow individuals to offset climatic stress, thereby providing a mechanism for persistence amidst warming conditions. Whereas the role of predation risk in food choice has been studied broadly, the extent to which individuals respond to thermoregulatory risk by changing resource preferences is unclear. We addressed whether individuals compensated for temperature-related reductions in foraging time by altering forage preferences, using the American pika Ochotona princeps as a model species.
We tested two hypotheses: Individuals exposed to more extreme daytime temperatures showed increased selection for high-nitrogen and for low-fiber vegetation, demonstrating strong support for the food-quality hypothesis. By contrast, pikas that experienced warmer conditions did not reduce selection for any of the three vegetation-quality metrics, as predicted by the food-availability hypothesis. By shifting resource-selection patterns, temperature-limited animals may be able to proximately buffer some of the negative effects associated with rapidly warming environments, provided that sufficient resources remain on the landscape.
Evaluation of nutritional and economic feed values of spent coffee grounds and Artemisia princeps residues as a ruminant feed using in vitro ruminal fermentation. Much research on animal feed has focused on finding alternative feed ingredients that can replace conventional ones e. The objective of this study was to evaluate the economic, as well as nutritional value of spent coffee grounds SCG and Japanese mugwort Artemisia princeps residues APR as alternative feed ingredients for ruminants.
We also investigated whether pre-fermentation using Lactobacillus spp. All the experimental diets for in vitro ruminal fermentation were formulated to contain a similar composition of crude protein, neutral detergent fiber and total digestible nutrients at 1x maintenance feed intake based on the dairy National Research Council NRC.
The control diet was composed of ryegrass, corn, soybean meal, whereas the treatments consisted of SCG, SCG fermented with Lactobacillus spp. Costs were lower for the all treatments, except FAPR, than that of the control. Full Text Available 'Od dkar b. She is a herder with two daughters b. She is a great storyteller and heard this story from her mother, 'Jig byed mtsho b. Ka Michael Moore'ist ja tema dokumentaalfilmist "Sicko".
Comparative morphology of premolar foramen in lagomorphs Mammalia: Glires and its functional and phylogenetic implications. Full Text Available Lagomorphs a group that consists of pikas , hares, rabbits and allies are notable for their conservative morphology retained for most of their over 50 million years evolutionary history. On the other hand, their remarkable morphological uniformity partly stems from a considerable number of homoplasies in cranial and dental structures that hamper phylogenetic analyses. The premolar foramen, an opening in the palate of lagomorphs, has been characterized as an important synapomorphy of one clade, Ochotonidae pikas.
Within Lagomorpha, however, its phylogenetic distribution is much wider, the foramen being present not only in all ochotonids but also in leporids and stem taxa; its morphology and incidence also varies considerably across the order, even intraspecifically. In this study, we provide a broad survey of the taxonomic distribution of the premolar foramen in extant and fossil Lagomorpha and describe in detail the morphological variation of this character within the group. Micro-computed tomography was used to examine the hard palate and infraorbital groove morphology in Poelagus Leporidae and Ochotona.
Scans revealed the course and contacts of the canal behind the premolar foramen and structural differences between the two crown clades. We propose that the premolar foramen has evolved independently in several lineages of Lagomorpha, and we discuss development and function of this foramen in the lagomorph skull. This study shows the importance of comprehensive studies on phylogenetically informative non-dental characters in Lagomorpha.
Tehingu katkemine pidurdab laienemist. Fidel Castro poolsajand Vabaduse Saarel. Opium was known and frequently used in Roman society. Medical practice recognized its usefulness as an analgesic, soporific, anti-tussic or anti-diarrheic agent, as well as other currently unsupported uses with quasi-magical properties. It was additionally used as an ingredient in antidotes, panaceas and poisons. The authors present a non-exhaustive compilation of opium use according to medical doctors, writers and encyclopaedists of the time.
Mythological and literary representations of the opium poppy reflected its diverse roles, being associated with prosperity and fertility, sleep, death and the underworld and with the art of medicine. Despite its free and routine use, there is no solid evidence of addiction, except the putative case of emperor Marcus Aurelius, consistently reported as one of the most likely cases of addiction to opium.
Expertly validated models and phylogenetically-controlled analysis suggests responses to climate change are related to species traits in the order lagomorpha. Full Text Available Climate change during the past five decades has impacted significantly on natural ecosystems, and the rate of current climate change is of great concern among conservation biologists.
Species Distribution Models SDMs have been used widely to project changes in species' bioclimatic envelopes under future climate scenarios. Here, we aimed to advance this technique by assessing future changes in the bioclimatic envelopes of an entire mammalian order, the Lagomorpha, using a novel framework for model validation based jointly on subjective expert evaluation and objective model evaluation statistics. SDMs were built using climatic, topographical, and habitat variables for all 87 lagomorph species under past and current climate scenarios.
Expert evaluation and Kappa values were used to validate past and current models and only those deemed 'modellable' within our framework were projected under future climate scenarios 58 species. Phylogenetically-controlled regressions were used to test whether species traits correlated with predicted responses to climate change. Climate change is likely to impact more than two-thirds of lagomorph species, with leporids rabbits, hares, and jackrabbits likely to undertake poleward shifts with little overall change in range extent, whilst pikas are likely to show extreme shifts to higher altitudes associated with marked range declines, including the likely extinction of Kozlov's Pika Ochotona koslowi.
Smaller-bodied species were more likely to exhibit range contractions and elevational increases, but showing little poleward movement, and fecund species were more likely to shift latitudinally and elevationally. Our results suggest that species traits may be important indicators of future climate change and we believe multi-species approaches, as demonstrated here, are likely to lead to more effective mitigation measures and conservation management. We strongly advocate studies minimising data gaps in our knowledge of.
Small mammals of the Mongolian mountain steppe region near Erdensant: Full Text Available Relatively little is known of the distribution, abundance and ecology of small mammals in Mongolia and as a result there is scant knowledge of the effects of environmental and anthropogenic factors on small mammal populations.
The aim of this study was to assess the occurrence of small mammals in mountain steppe habitat from live-trapping and analysis of mammal remains from raptor pellets and below nests. During live-trapping, root voles Microtus oeconemus were the most commonly caught species accounting for The three species caught on the trapping grid appeared to avoid competition for resources through both temporal and spatial differences in the use of available habitat.
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Mammals identified from raptor pellets and other remains included the grey hamster Cricatulus migratorius , Siberian marmot Marmota sibirica , red fox Vulpes vulpes , long-tailed souslik Citellus undulatus and the Daurian mole Myospalax aspalax. Results are discussed in terms of their relevance to the conservation of mammals in Mongolia and their co-existence with livestock and humans. Pow, Punch, Pika , and Chu: As multimodal works, comics are characterized as much by their use of language as by the style of their images.
The Late Miocene species. Mammalia, Lagomorpha of Moldova: This book is not yet featured on Listopia. Dec 28, Marinho Lopes rated it liked it. Os poemas, apesar de bastante simples, denotam bem o talento do escritor para a musicalidade na sua escrita. Rui Miguel Mesquita rated it really liked it May 03, Paulo Bugalho is currently reading it Oct 07, Vanni marked it as to-read Dec 20, Tiago Aires marked it as to-read Oct 23, There are no discussion topics on this book yet. Bernardim Ribeiro was a Renaissance Portuguese poet and writer. Books by Bernardim Ribeiro.
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