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Kurt E Galbreath - One of the best experts on this subject based on the ideXlab platform.
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chromosome level reference genome assembly for the american pika Ochotona princeps
Journal of Heredity, 2021Co-Authors: Bryson M F Sjodin, Kurt E Galbreath, Hayley C Lanier, Michael A RusselloAbstract:The American pika (Ochotona princeps) is an alpine lagomorph found throughout western North America. Primarily inhabiting talus slopes at higher elevations (>2,000 m), American pikas are well-adapted to cold, montane environments. Warming climates on both historical and contemporary scales have contributed to population declines in American pikas, positioning them as a focal mammalian species for investigating the ecological effects of climate change. To support and expand on-going research efforts, here we present a highly contiguous and annotated reference genome assembly for the American pika (OchPri4.0). This assembly was produced using Dovetail de novo proximity ligation methods and annotated through the NCBI Eukaryotic Genome Annotation pipeline. The resulting assembly was chromosome-scale, with a total length of 2.23 Gb across 9,350 scaffolds and a scaffold N50 of 75.8 Mb. The vast majority (>97%) of the total assembly length was found within 36 large scaffolds; 33 of these scaffolds correlated to whole autosomes, while the X chromosome was covered by three large scaffolds. Additionally, we identified 17 enriched gene ontology terms among American pika-specific genes putatively related to adaptation to high elevation environments. This high-quality genome assembly will serve as a springboard for exploring the evolutionary underpinnings of behavioral, ecological, and taxonomic diversification in pikas, as well as broader-scale eco-evolutionary questions pertaining to cold-adapted species in general.
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return to beringia parasites reveal cryptic biogeographic history of north american pikas
Proceedings of The Royal Society B: Biological Sciences, 2012Co-Authors: Kurt E Galbreath, Eric P HobergAbstract:Traditional concepts of the Bering Land Bridge as a zone of predominantly eastward expansion from Eurasia and a staging area for subsequent colonization of lower latitudes in North America led to early inferences regarding biogeographic histories of North American faunas, many of which remain untested. Here we apply a host–parasite comparative phylogeographical (HPCP) approach to evaluate one such history, by testing competing biogeographic hypotheses for five lineages of host-specific parasites shared by the collared pika (Ochotona collaris) and American pika (Ochotona princeps) of North America. We determine whether the southern host species (O. princeps) was descended from a northern ancestor or vice versa. Three parasite phylogenies revealed patterns consistent with the hypothesis of a southern origin, which is corroborated by four additional parasite lineages restricted to O. princeps. This finding reverses the traditional narrative for the origins of North American pikas and highlights the role of dispersal from temperate North America into Beringia in structuring northern diversity considerably prior to the Holocene. By evaluating multiple parasite lineages simultaneously, the study demonstrates the power of HPCP for resolving complex biogeographic histories that are not revealed by characteristics of the host alone.
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discovery of new ohbayashinema spp nematoda heligmosomoidea in Ochotona princeps and Ochotona cansus lagomorpha ochotonidae from western north america and central asia with considerations of historical biogeography
Journal of Parasitology, 2010Co-Authors: M C Durettedesset, Kurt E Galbreath, Eric P HobergAbstract:Abstract 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. sp. and Ohbayashinema aspeira n. sp., are parasitic in American pika, Ochotona princeps. 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. nearctica based on the number of cuticular ridges at the mid-body. 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. sp., is parasitic in Gansu pika, Ochotona cansus, from China. It is similar to Ohbayashinema erbaevae parasitic in Ochotona dauurica from Buriatia and Ohbayashinema ochotoni in Ochotona macrotis from Nepal, bas...
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Isolation and introgression in the Intermountain West: contrasting gene genealogies reveal the complex biogeographic history of the American pika (Ochotona princeps)
Journal of Biogeography, 2010Co-Authors: Kurt E Galbreath, David J Hafner, Kelly R. Zamudio, Kelly AgnewAbstract:Aim We studied the history of colonization, diversification and introgression among major phylogroups in the American pika, Ochotona princeps (Lagomorpha), using comparative and statistical phylogeographic methods. Our goal was to understand how Pleistocene climatic fluctuations have shaped the distribution of diversity at mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) loci in this alpine specialist.
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why museums matter a tale of pinworms oxyuroidea heteroxynematidae among pikas Ochotona princeps and o collaris in the american west
Journal of Parasitology, 2009Co-Authors: Eric P Hoberg, Kurt E Galbreath, Patricia A PilittAbstract:Permanent and well-supported museum or natural history 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 characteristic of pikas (Ochotona spp.) in the American west. These studies address the taxonomy for pinworms of the Labiostomatinae and the problems associated with the absence of adequate type series and vouchers and with misidentifications in original descriptions. We demonstrate that the types for Labiostomum (Labiostomum) coloradensis are identical to some specimens in the syntype series representing L. (Eugenuris) utahensis, although the published descriptions are in disagreement. Both are identical to L. (Eugenuris) talkeetnaeuris and, as a consequence, are reduced as junior synonyms. Only 2 species of large pinworms, namely L. (Labiostomum) rauschi and L. (Eugenuris) talkeetnaeuris, are widely distributed in Ochotona collaris and O. princeps. Although this serves to clarify the taxonomy for species in these genera, prior records remain confused, as representative voucher specimens from all major surveys in North America were never submitted to museum collections. We strongly suggest that type and voucher series should not be held in private or personal collections, where such are eventually lost, discarded, or destroyed through neglect due to inattention and the absence of curation. The potential to accumulate meaningful baselines for assessment of environmental change is jeopardized if materials from survey and inventory are not routinely submitted to museum collections. The capacity of museum repositories, as a focus for systematics, ecology, and evolutionary studies and for the development of resources for biodiversity informatics, continues to be undervalued and poorly utilized by a cadre of scientists who are dependant on accurate and definitive information that transcends specific disciplines.
Margarita A. Erbajeva - One of the best experts on this subject based on the ideXlab platform.
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The ochotonids of Eurasia: Biochronology and taxonomic diversity
Biology Bulletin, 2016Co-Authors: Margarita A. ErbajevaAbstract:The ochotonid faunas of Eurasia and North America from the Oligocene to the present time are reviewed. The pika family (Ochotonidae Thomas 1897) belongs to the order Lagomorpha, which includes five families: Ochotonidae, Mimotonidae Li 1978, Leporidae Fischer 1817 (hares), Palaeolagidae Dice 1929, and Prolagidae Gureev 1960. The family Ochotonidae consists of two subfamilies: Sinolagomyinae Gureev, 1960 and Ochotoninae Thomas, 1897 and comprises a total of 17 genera. Originating in Central Asia at the beginning of the Late Oligocene, pikas flourished during the Late Oligocene. The highest taxonomic diversity of pikas can be found in the Miocene and Pliocene; towards the Pleistocene, the ochotonid fauna declined. Only one genus, Ochotona, remained extant by the end of the Pleistocene. The genus includes a total of 38 known extinct taxa and 28 extant species.
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late cenozoic asian ochotonidae taxonomic diversity chronological distribution and biostratigraphy
Quaternary International, 2015Co-Authors: Margarita A. Erbajeva, Lawrence J. Flynn, Nadezhda AlexeevaAbstract:Comprehensive studies on lagomorph collections on ochotonids (pikas) from Mongolia, China, and Kazakhstan were undertaken by the authors. Additional fossils collected by joint Austrian–Mongolian teams from Central Asia, in particular from the Valley of Lakes of Mongolia, have yielded many new data on the taxonomic diversity and stratigraphic ranges of members of this ancient group of mammals. Ochotonids (Ochotonidae, Lagomorpha) originated during the Late Oligocene in Central Asia, but they were not numerous. From the early Late Oligocene through the Pleistocene, three main evolutionary stages in ochotonid development were recognized. The earliest Oligocene stage is characterized by existence of rooted ochotonids of the genera Sinolagomys and Bohlinotona. During the following Early to Middle Miocene stage, diverse genera of rootless ochotonids flourished; they displayed the highest taxonomic diversity and occupied vast territories of Eurasia. The Late Miocene–Pliocene stage is characterized by increasing diversity of the genus Ochotona and dispersal throughout the Northern Hemisphere. In the Pleistocene, ochotonids decreased both in abundance and variety of taxa. At present, the genus Ochotona consists of 28 extant species.
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new data on late miocene pleistocene ochotonids ochotonidae lagomorpha from north china
Acta Zoologica Cracoviensia, 2005Co-Authors: Margarita A. Erbajeva, Shaohua ZhengAbstract:Detailed study of ochotonids from the Late Miocene-Pleistocene of North China revealed more than fifteen ochotonid taxa. They include Ochotona plicodenta sp. nov., O. gracilis sp. nov., O. lingtaica sp. nov., O. youngi sp. nov., O. magna sp. nov., O. zhangi sp.nov., O. cf. O. lagreli, O. cf. O. minor, O.c f. O. cansus, O. aff. O. tibetana, O. aff. O. bazarovi, O. aff. O. dodogolica, O. aff. O. intermedia, Ochotona sp. (small), O. complici- dens and O. complicidens near to Ochotonoma. Of these species, the former ten are the en- demics to China and the other forms are widely-distributed in Asia. Evolutionary history of ochotonids is shortly discussed.
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new ochotonids lagomorpha from the pleistocene of france
Geodiversitas, 2001Co-Authors: Margarita A. Erbajeva, Sophie Montuire, Jean ChalineAbstract:The mammalian fauna of insectivores, rodents and lagomorphs found at Les Valerots (Nuits-Saint-Georges, Cote-d’Or) dated as early Pleistocene based on the association of Hypolagus Dice, 1917, Mimomys savini Hinton, 1926, Allophaiomys Kormos, 1932 and Dicrostonyx Gloger, 1841 includes only two species of lagomorphs belonging to the families Leporidae and Ochotonidae. Examination of the ochotonid remains shows that the pika from the Les Valerots site is a new taxon, Ochotona valerotae n. sp. Study of the representative fossil material of Ochotona pusilla Pallas, 1768 found at the localities of La Fage (Correze) and of Baume de Gigny (Jura) in France reveals that the small late Pleistocene pika can be described as a new subspecies of Ochotona pusilla: Ochotona pusilla occidentalis n. ssp. The history of Ochotona pusilla in Eurasia is reviewed.
Pedro José Esteves - One of the best experts on this subject based on the ideXlab platform.
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Endogenization of mouse mammary tumor virus (MMTV)-like elements in genomes of pikas (Ochotona sp.)
Virus Research, 2015Co-Authors: Ana Lemos De Matos, José Melo-ferreira, Patricia De Sousa-pereira, Andrey A. Lissovsky, Pedro José EstevesAbstract:Abstract Despite the finding in European rabbit and other leporid genomes of the first ever described endogenous lentivirus and of a European rabbit exclusive endogenous gammaretrovirus, until now no exogenous retroviruses have been isolated in Lagomorpha species. Nevertheless, looking for the presence of endogenous retroviruses (ERVs) in the species genomes could lead to the discovery of retroviral lineages yet to be found in Lagomorpha. Different mammalian genomes harbor endogenous viral sequences phylogenetically close to the betaretrovirus mouse mammary tumor virus (MMTV), propelling us to look for such retroviral “fossil” in American pika ( Ochotona princeps ) and European rabbit ( Oryctolagus cuniculus ) genomes. By performing genomic mining using MMTV gag and LTR as query sequences, we found that such viral elements were absent from the European rabbit genome. Oppositely, significant matches were found in American pika, and more importantly, a nearly complete MMTV-like virus (Pika-BERV) was identified. Using Pika-BERV gag and LTR as templates, we found similar sequences endogenized in different pika ( Ochotona sp.) species. The orthology of the LTR flanking region between some pika species supported shared ancestry of specific endogenous betaretroviruses, while in other pika species similar sequences, but not orthologous, should have resulted from independent insertions. Our study supports the possible existence of infecting exogenous betaretroviruses for a long term, after the divergence of Ochotonidae from Leporidae, but yet to be identified.
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pseudogenization of ccl14 in the ochotonidae pika family
Innate Immunity, 2015Co-Authors: Fabiana Neves, Andrey A. Lissovsky, Joana Abrantes, Pedro José EstevesAbstract:The interaction between chemokines and their receptors is crucial for inflammatory cell trafficking. CCL14 binds with high affinity to CCR5. In leporids, CCR5 underwent gene conversion with CCR2. The study of CCR5 ligands in leporid species showed that CCL8 is pseudogenized, while CCL3, CCL4 and CCL5 are functional. Here, we study the evolution of CCL14 in mammals with emphasis in the order Lagomorpha. By employing maximum likelihood methods we detected six sites under positive selection. Some of these sites are located in regions crucial for CCL14 activation and binding to receptors. Sequencing of CCL14 in Ochotona species showed that O. princeps, O. pallasi, O. alpina and O. turuchanensis have a mutation at the start codon (Met > Thr), while O. hoffmanni, O. mantchurica, O. dauurica and O. rufescens present the mammalian conserved Met. Ochotona hyperborea has the two alleles. In O. pusilla, CCL14 is a pseudogene due to a seven base pair insertion. Like CCL3, CCL4 and CCL5, CCL14 is functional in all lep...
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The phylogeny of pikas (Ochotona) inferred from a multilocus coalescent approach
Molecular Phylogenetics and Evolution, 2015Co-Authors: José Melo-ferreira, Ana Lemos De Matos, Helena Areal, Miguel Carneiro, Andrey A. Lissovsky, Pedro José EstevesAbstract:Abstract The clarification of the systematics of pikas (genus Ochotona) has been hindered by largely overlapping morphological characters among species and the lack of a comprehensive molecular phylogeny. Here we estimate the first multilocus phylogeny of the genus to date, by analysing 12 nuclear DNA markers (total of 7.5 Kb) in 11 species of pikas from the four classified subgenera (Pika, Ochotona, Lagotona and Conothoa) using a multispecies coalescent-based framework. The species-tree confirmed the subgeneric classification by retrieving as monophyletic the subgenera represented here by more than one species. Contrary to previous phylogenies based on mtDNA alone, Lagotona was found to be sister to Pika. Also, support for the monophyly of the alpina group was not strong, thus caution should be used in future analyses of this group. A relaxed molecular clock calibrated using the Ochotonidae–Leporidae divergence resulted in more recent estimates of divergence times relative to previous studies. Strong concordance with inferences based on fossil records was found, suggesting that the initial diversification of the genus took place by the end of late Miocene. Finally, this work sets up methodologies and gathers molecular markers that can be used to extend the understanding of the evolutionary history of the genus.
Andrey A. Lissovsky - One of the best experts on this subject based on the ideXlab platform.
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An Intriguing Shift Occurs in the Novel Protein Phosphatase 1 Binding Partner, TCTEX1D4: Evidence of Positive Selection in a Pika Model
2016Co-Authors: Luís Korrodi-gregório, Andrey A. Lissovsky, Ana Margarida Lopes, Sara L. C. Esteves, Ra Afonso, Pedro JoséAbstract:T-complex testis expressed protein 1 domain containing 4 (TCTEX1D4) contains the canonical phosphoprotein phosphatase 1 (PPP1) binding motif, composed by the amino acid sequence RVSF. We identified and validated the binding of TCTEX1D4 to PPP1 and demonstrated that indeed this protein is a novel PPP1 interacting protein. Analyses of twenty-one mammalian species available in public databases and seven Lagomorpha sequences obtained in this work showed that the PPP1 binding motif 90RVSF93 is present in all of them and is flanked by a palindromic sequence, PLGS, except in three species of pikas (Ochotona princeps, O. dauurica and O. pusilla). Furthermore, for the Ochotona species an extra glycosylation site, motif 96NLS98, and the loss of the palindromic sequence were observed. Comparison with other lagomorphs suggests that this event happened before the Ochotona radiation. The dN/dS for the sequence region comprising the PPP1 binding motif and the flanking palindrome highly supports the hypothesis that for Ochotona species this region has been evolving under positiv
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a new subspecies of manchurian pika Ochotona mantchurica lagomorpha ochotonidae from the lesser khinggan range china
Russian journal of theriology, 2015Co-Authors: Andrey A. LissovskyAbstract:I examined 14 craniometric features of 128 specimens of Ochotona mantchurica from the entire distribution range. A craniometric analysis revealed at least three major groups with detached geographical distribution. The race of O. mantchurica from the southern part of the Lesser Khinggan Range has the same level of morphological peculiarity as two other subspecies: O. m. scorodumovi from the Russian Transbaikalia and O. m. mantchurica from the Greater Khinggan Range, together with the northern part of the Lesser Khinggan Range. The distribution area of this race is separated from the rest of the species distribution range by a wide band of lowly suitable habitats. No nominal taxa were described from the southern part of the Lesser Khinggan Range, and the race in question was described here as a new subspecies: O. m. loukashkini ssp. nov.
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Endogenization of mouse mammary tumor virus (MMTV)-like elements in genomes of pikas (Ochotona sp.)
Virus Research, 2015Co-Authors: Ana Lemos De Matos, José Melo-ferreira, Patricia De Sousa-pereira, Andrey A. Lissovsky, Pedro José EstevesAbstract:Abstract Despite the finding in European rabbit and other leporid genomes of the first ever described endogenous lentivirus and of a European rabbit exclusive endogenous gammaretrovirus, until now no exogenous retroviruses have been isolated in Lagomorpha species. Nevertheless, looking for the presence of endogenous retroviruses (ERVs) in the species genomes could lead to the discovery of retroviral lineages yet to be found in Lagomorpha. Different mammalian genomes harbor endogenous viral sequences phylogenetically close to the betaretrovirus mouse mammary tumor virus (MMTV), propelling us to look for such retroviral “fossil” in American pika ( Ochotona princeps ) and European rabbit ( Oryctolagus cuniculus ) genomes. By performing genomic mining using MMTV gag and LTR as query sequences, we found that such viral elements were absent from the European rabbit genome. Oppositely, significant matches were found in American pika, and more importantly, a nearly complete MMTV-like virus (Pika-BERV) was identified. Using Pika-BERV gag and LTR as templates, we found similar sequences endogenized in different pika ( Ochotona sp.) species. The orthology of the LTR flanking region between some pika species supported shared ancestry of specific endogenous betaretroviruses, while in other pika species similar sequences, but not orthologous, should have resulted from independent insertions. Our study supports the possible existence of infecting exogenous betaretroviruses for a long term, after the divergence of Ochotonidae from Leporidae, but yet to be identified.
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pseudogenization of ccl14 in the ochotonidae pika family
Innate Immunity, 2015Co-Authors: Fabiana Neves, Andrey A. Lissovsky, Joana Abrantes, Pedro José EstevesAbstract:The interaction between chemokines and their receptors is crucial for inflammatory cell trafficking. CCL14 binds with high affinity to CCR5. In leporids, CCR5 underwent gene conversion with CCR2. The study of CCR5 ligands in leporid species showed that CCL8 is pseudogenized, while CCL3, CCL4 and CCL5 are functional. Here, we study the evolution of CCL14 in mammals with emphasis in the order Lagomorpha. By employing maximum likelihood methods we detected six sites under positive selection. Some of these sites are located in regions crucial for CCL14 activation and binding to receptors. Sequencing of CCL14 in Ochotona species showed that O. princeps, O. pallasi, O. alpina and O. turuchanensis have a mutation at the start codon (Met > Thr), while O. hoffmanni, O. mantchurica, O. dauurica and O. rufescens present the mammalian conserved Met. Ochotona hyperborea has the two alleles. In O. pusilla, CCL14 is a pseudogene due to a seven base pair insertion. Like CCL3, CCL4 and CCL5, CCL14 is functional in all lep...
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The phylogeny of pikas (Ochotona) inferred from a multilocus coalescent approach
Molecular Phylogenetics and Evolution, 2015Co-Authors: José Melo-ferreira, Ana Lemos De Matos, Helena Areal, Miguel Carneiro, Andrey A. Lissovsky, Pedro José EstevesAbstract:Abstract The clarification of the systematics of pikas (genus Ochotona) has been hindered by largely overlapping morphological characters among species and the lack of a comprehensive molecular phylogeny. Here we estimate the first multilocus phylogeny of the genus to date, by analysing 12 nuclear DNA markers (total of 7.5 Kb) in 11 species of pikas from the four classified subgenera (Pika, Ochotona, Lagotona and Conothoa) using a multispecies coalescent-based framework. The species-tree confirmed the subgeneric classification by retrieving as monophyletic the subgenera represented here by more than one species. Contrary to previous phylogenies based on mtDNA alone, Lagotona was found to be sister to Pika. Also, support for the monophyly of the alpina group was not strong, thus caution should be used in future analyses of this group. A relaxed molecular clock calibrated using the Ochotonidae–Leporidae divergence resulted in more recent estimates of divergence times relative to previous studies. Strong concordance with inferences based on fossil records was found, suggesting that the initial diversification of the genus took place by the end of late Miocene. Finally, this work sets up methodologies and gathers molecular markers that can be used to extend the understanding of the evolutionary history of the genus.
Andrew T. Smith - One of the best experts on this subject based on the ideXlab platform.
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conservation status of american pikas Ochotona princeps
Journal of Mammalogy, 2020Co-Authors: Andrew T. SmithAbstract:The American pika (Ochotona princeps) is commonly perceived as a species that is at high risk of extinction due to climate change. The purpose of this review is two-fold: to evaluate the claim that climate change is threatening pikas with extinction, and to summarize the conservation status of the American pika. Most American pikas inhabit major cordilleras, such as the Rocky Mountain, Sierra Nevada, and Cascade ranges. Occupancy of potential pika habitat in these ranges is uniformly high and no discernible climate signal has been found that discriminates between the many occupied and relatively few unoccupied sites that have been recently surveyed. Pikas therefore are thriving across most of their range. The story differs in more marginal parts of the species range, primarily across the Great Basin, where a higher percentage of available habitat is unoccupied. A comprehensive review of Great Basin pikas revealed that occupied sites, sites of recent extirpation, and old sites, were regularly found within the same geographic and climatic space as extant sites, and suggested that pikas in the Great Basin tolerated a broader set of habitat and climatic conditions than previously understood. Studies of a small subset of extirpated sites in the Great Basin and in California found that climate variables (most notably measures of hot temperature) were associated more often with extirpated sites than occupied sites. Importantly, upward contraction of the lower elevation boundary also was found at some sites. However, models that incorporated variables other than climate (such as availability of upslope talus habitat) often were better predictors of site persistence. Many extirpations occurred on small habitat patches, which were subject to stochastic extinction, as informed by a long-term pika metapopulation study in Bodie, California. In addition, several sites may have been compromised by cattle grazing or other anthropogenic factors. In contrast, several low, hot sites (Bodie, Mono Craters, Craters of the Moon National Monument and Preserve, Lava Beds National Monument, Columbia River Gorge) retain active pika populations, demonstrating the adaptive capacity and resilience of pikas in response to adverse environmental conditions. Pikas cope with warm temperatures by retreating into cool interstices of their talus habitat and augment their restricted daytime foraging with nocturnal activity. Pikas exhibit significant flexibility in their foraging tactics and are highly selective in their choice of available vegetation. The trait that places pikas at greatest risk from climate change is their poor dispersal capability. Dispersal is more restricted in hotter environments, and isolated low-elevation sites that become extirpated are unlikely to be recolonized in a warming climate. The narrative that American pikas are going extinct appears to be an overreach. Pikas are doing well across most of their range, but there are limited, low-elevation losses that are likely to be permanent in what is currently marginal pika habitat. The resilience of pikas in the face of climate change, and their ability or inability to persist in marginal, hot environments, will continue to contribute to our understanding of the impact of climate change on individual species.
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distribution climatic relationships and status of american pikas Ochotona princeps in the great basin usa
Arctic Antarctic and Alpine Research, 2018Co-Authors: Constance I Millar, Andrew T. Smith, Diane L Delany, Kimberly A Hersey, Mackenzie R Jeffress, Jane K Van Gunst, Robert D WestfallAbstract:ABSTRACTTo advance understanding of the distribution, climatic relationships, and status of American pikas (Ochotona princeps) in the Great Basin, United States, we compiled 2,387 records of extant pika sites surveyed since 2005, 89 records of documented extirpated sites (resurvey of historic sites), and 774 records of sites with old sign only. Extant sites extended across five degrees latitude and ten degrees longitude, encompassed six subregions, traversed forty mountain ranges, spanned 2,378 m in elevation (1,631–4,009 m), and comprised three of five currently described pika subspecies. A climate envelope for extant sites using the PRISM climate model expands the range of temperature and precipitation values that have been previously described. Extirpated and old-sign sites were mostly found within the geographic and climatic space of extant sites, but often in warmer and drier portions. Considerable overlap of extirpated, old, and extant groups within the same climate space suggests that nonclimatic f...
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plateau pika Ochotona curzoniae poisoning campaign reduces carnivore abundance in southern qinghai china
Mammal Study, 2016Co-Authors: Andrew T. Smith, Jesse Senko, Marcelino U SiladanAbstract:Abstract. The plateau pika (Ochotona curzoniae), a small burrowing lagomorph that occupies the high alpine grasslands of the Qinghai-Tibetan Plateau (QTP), has been subject to a massive eradication campaign in China since the late 1950′s under the assumption that it promotes grassland degradation. However, mounting evidence suggests that pikas are a keystone species that provide critical ecological services in the alpine meadow ecosystem. Since the implementation of pika control programs, few studies have investigated the potential impacts of pika poisoning on native carnivore species. In 2007 we investigated the impact of pika poisoning on carnivores in southern Qinghai Province, China. Our results show a decrease in the abundance of carnivores from areas where pikas had been poisoned compared with non-poisoned sites, suggesting that the eradication of pikas at regional scales may alter or disrupt ecological communities on the QTP.
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population resilience in an american pika Ochotona princeps metapopulation
Journal of Mammalogy, 2015Co-Authors: Andrew T. Smith, John D NagyAbstract:Population resilience in a metapopulation of American pikas (Ochotona princeps) at Bodie, California, was investigated with a series of 18 detailed occupancy surveys conducted between 1989 and 2010. These were compared with earlier 1972 and 1977 censuses and earlier historical records of pikas at Bodie. There is concern that American pikas may be increasingly vulnerable to warm temperatures due to climate change, and this investigation represents the longest study of the species in a relatively low-elevation (warm) environment. The Bodie pika population represents one of the best mammalian examples of a classic metapopulation system. Annual number of observed patch extinctions (total = 114) and recolonizations (109) varied greatly among the 18 census intervals. There has been no decline in percent of patches occupied in the northern half of the study area since 1972, and the number of documented pikas in the north in recent surveys exceeded the numbers found in 1972 and 1977. In contrast, the southern hal...
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reevaluation of several taxa of chinese lagomorphs mammalia lagomorpha described on the basis of pelage phenotype variation
Mammalian Biology, 2012Co-Authors: Deyan Ge, Andrey A. Lissovsky, Cheng Cheng, Andrew T. Smith, Qisen YangAbstract:Abstract Melanism is a common phenomenon in the animal kingdom. While the occurrence of melanism in lagomorphs has been less studied, this phenomenon has led to systematic confusion among different forms of pikas ( Ochotona ) and hares ( Lepus ). Within Ochotona , the Pianma black pika ( O. nigritia ) was established primarily based on its pelage phenotype variation compared with the sympatric Forrest's pika ( O. forresti ). The Gaoligong pika ( O. gaoligongensis ) was also described based on pelage color differences with O. forresti . However, the specific status of these two taxa has been questioned for several years. We conducted a detailed examination of the cranial characters used for the initial diagnosis of each of these forms ( O. forresti , O. gaoligongensis and O. nigritia ). Insignificant differences were displayed among these species, thus contradicting the classification of O. gaoligongensis and O. nigritia as separate species. Within Lepus , the Manchurian black hare ( Lepus melainus ) was also initially described based on the melanistic pelage possessed by this form. We conducted a detailed examination of the cranial characteristics of L. melainus and the sympatric Manchurian hare ( L. mandshuricus ) and confirmed the synonomy of these forms; L. melainus represents melanistic individuals of L. mandshuricus . These taxonomic mistakes probably resulted from underestimating the prevalence of melanism and the potential for adaptative variation of pelage coloration in nature. A more detailed study on the genetic background leading to the occurrence of melanistic lagomorphs is needed.