Opera Mundi: a weekly report on the economy of the Common Market. No. 530, September 8 - September 14, 1969.

No abstract

Echinococcus multilocularis and Echinococcus shiquicus in a small mammal community on the eastern Tibetan Plateau : host species composition, molecular prevalence, and epidemiological implications

Background The eastern part of the Tibetan Plateau is now recognized as an endemic region with the highest reported human infection rates in the world of human alveolar echinococcosis (AE) caused by Echinococcus multilocularis. Existing epidemiological studies on AE have mainly focused on the synanthropic environment, while basic parasitological and ecological aspects in wildlife host species remain largely unknown, especially for small mammal hosts. Therefore, we examined small mammal host species composition, occurrence, and the prevalence of both E. multilocularis and E. shiquicus in Shiqu County (Sichuan Province, China), eastern Tibetan Plateau. Results In total, 346 small mammals from five rodent and one pika species were trapped from four randomly set 0.25 ha square plots. Two vole species, Lasiopodomys fuscus (n = 144) and Microtus limnophilus (n = 44), and the plateau pika (Ochotona curzoniae) (n = 135), were the three most-dominant species trapped. Although protoscoleces of E. multilocularis and E. shiquicus were only observed in L. fuscus and O. curzoniae, respectively, cox1 and nad1 gene DNA of E. shiquicus was detected in all the small mammal species except for Neodon irene, whereas E. multilocularis was detected in the three most-dominant species. The overall molecular prevalence of Echinococcus species was 5.8 (95% CI: 3.3–8.2%) ~ 10.7% (95% CI: 7.4–14.0%) (the conservative prevalence to the maximum prevalence with 95% CI in parentheses), whereas for E. multilocularis it was 4.3 (95% CI: 2.2–6.5%) ~ 6.7% (95% CI: 4.0–9.3%), and 1.5 (95% CI: 0.2–2.7%) ~ 4.1% (95% CI: 2.0–6.1%) for E. shiquicus. The prevalence of both E. multilocularis and E. shiquicus, was significantly higher in rodents (mainly voles) than in pikas. Phylogenetic analyses revealed that Echinococcus haplotypes of cox1 from small mammal hosts were actively involved in the sylvatic and anthropogenic transmission cycles of E. multilocularis in the eastern Tibetan Plateau. Conclusions In contrast to previous studies, the current results indicated that rodent species, rather than pikas, are probably more important natural intermediate hosts of E. multilocularis and E. shiquicus in the eastern Tibetan Plateau. Thus, understanding interspecific dynamics between rodents and pikas is essential to studies of the echinococcosis transmission mechanism and human echinococcosis prevention in local communities. Keywords: Echinococcus multilocularis, E. shiquicus, Small mammal Prevalence, Tibetan Platea

Diversification Of Muroid Rodents Driven By The Late Miocene Global Cooling

Late Miocene, 8 to 6 million years ago (Ma), climatic changes brought about dramatic floral and faunal changes. Cooler and drier climates that prevailed in the Late Miocene led to expansion of grasslands and retreat of forests at a global scale. Palaeogeographic studies suggest a global vegetation change causing an abrupt increase in C4 plant biomass while C3 biomass decreased between 8 and 6 Ma. Subsequent cycles of cooler and drier climatic conditions during the Mid-Pliocene (3.5–3 Ma) and Pleistocene (2.8–2.5; 1.8–1.6; 1.0–0.8 Ma) also caused forests to retreat into isolated refugia which played an important role in events that led speciation and radiation of Muroid (Order Rodentia, Superfamily Muroidea) rodents. Muroid rodents are comprised of 6 families (Placanthomyidae, Spalacidae, Calomyscidae, Nesomyidae, Cricetidae, and Muridae) and make up close to one-third of named mammal species. Family Cricetidae and Muridae are especially speciose (containing ~1600 species altogether) and much of the diversity within these families arose during or after the Late Miocene. My dissertation deals with the systematics and historical biogeography of these fast-evolving groups of rodents with an emphasis on the genera Apodemus and Hybomys (Subfamily Murinae, Family Muridae), and Neodon (Subfamily Arvicolinae, Family Cricetidae). Habitat specialists such as Apodemus that occupy broadleaf forests, and Hybomys that occupy rainforests were likely isolated in forest refugia after the retreat of forests facilitating allopatric speciation. While voles in the subfamily Arvicolinae, that are associated with grasslands, expanded their range when forests retreated and speciated when grasslands retreated. In addition, field work carried out for this project in Nepal included several localities previously not sampled for small mammals. Most of Nepal is poorly surveyed and the first chapter focuses on the history of mammalogical surveys in Nepal and adds new localities for small mammal species, expanding the known range of the Nepalese endemic Himalayan wood mouse (Apodemus gurkha)

The evolutionary radiation of Arvicolinae rodents (voles and lemmings): relative contribution of nuclear and mitochondrial DNA phylogenies

BACKGROUND: Mitochondrial and nuclear genes have generally been employed for different purposes in molecular systematics, the former to resolve relationships within recently evolved groups and the latter to investigate phylogenies at a deeper level. In the case of rapid and recent evolutionary radiations, mitochondrial genes like cytochrome b (CYB) are often inefficient for resolving phylogenetic relationships. One of the best examples is illustrated by Arvicolinae rodents (Rodentia; Muridae), the most impressive mammalian radiation of the Northern Hemisphere which produced voles, lemmings and muskrats. Here, we compare the relative contribution of a nuclear marker – the exon 10 of the growth hormone receptor (GHR) gene – to the one of the mitochondrial CYB for inferring phylogenetic relationships among the major lineages of arvicoline rodents. RESULTS: The analysis of GHR sequences improves the overall resolution of the Arvicolinae phylogeny. Our results show that the Caucasian long-clawed vole (Prometheomys schaposnikowi) is one of the basalmost arvicolines, and confirm that true lemmings (Lemmus) and collared lemmings (Dicrostonyx) are not closely related as suggested by morphology. Red-backed voles (Myodini) are found as the sister-group of a clade encompassing water vole (Arvicola), snow vole (Chionomys), and meadow voles (Microtus and allies). Within the latter, no support is recovered for the generic recognition of Blanfordimys, Lasiopodomys, Neodon, and Phaiomys as suggested by morphology. Comparisons of parameter estimates for branch lengths, base composition, among sites rate heterogeneity, and GTR relative substitution rates indicate that CYB sequences consistently exhibit more heterogeneity among codon positions than GHR. By analyzing the contribution of each codon position to node resolution, we show that the apparent higher efficiency of GHR is due to their third positions. Although we focus on speciation events spanning the last 10 million years (Myr), CYB sequences display highly saturated codon positions contrary to the nuclear exon. Lastly, variable length bootstrap predicts a significant increase in resolution of arvicoline phylogeny through the sequencing of nuclear data in an order of magnitude three to five times greater than the size of GHR exon 10. CONCLUSION: Our survey provides a first resolved gene tree for Arvicolinae. The comparison of CYB and GHR phylogenetic efficiency supports recent assertions that nuclear genes are useful for resolving relationships of recently evolved animals. The superiority of nuclear exons may reside both in (i) less heterogeneity among sites, and (ii) the presence of highly informative sites in third codon positions, that evolve rapidly enough to accumulate synapomorphies, but slow enough to avoid substitutional saturation

Karyotype and X-Y chromosome pairing in the Sikkim vole (Microtus (Neodon) sikimensis)

Pairing of the X and Y chromosomes during meiotic prophase and the G- and C-banding patterns were analysed in Microtus sikimensis. The karyotype of M. sikimensis from central Nepal, has 2n= 48 and FNa = 56. It has been derived from the all single-armed karyotype of M. carruthersi through a unique course of evolution. There is a synapsis between the X and Y chromosomes at pachytene and end-to-end association from diakinesis to metaphase I. Microtus sikimensis has no close karyological or morphological relationship to the other synaptic species studied so far. These data confirm that several species or lineages with synaptic condition exist in the genus Microtus, and that the ancestor of Microtus had synaptic sex chromosomes.journal articl

The accelerating influence of humans on mammalian macroecological patterns over the late Quaternary

The transition of hominins to a largely meat-based diet ~1.8 million years ago led to the exploitation of other mammals for food and resources. As hominins, particularly archaic and modern humans, became increasingly abundant and dispersed across the globe, a temporally and spatially transgressive extinction of large-bodied mammals followed; the degree of selectivity was unprecedented in the Cenozoic fossil record. Today, most remaining large-bodied mammal species are confined to Africa, where they coevolved with hominins. Here, using a comprehensive global dataset of mammal distribution, life history and ecology, we examine the consequences of “body size downgrading” of mammals over the late Quaternary on fundamental macroecological patterns. Specifically, we examine changes in species diversity, global and continental body size distributions, allometric scaling of geographic range size with body mass, and the scaling of maximum body size with area. Moreover, we project these patterns toward a potential future scenario in which all mammals currently listed as vulnerable on the IUCN\u27s Red List are extirpated. Our analysis demonstrates that anthropogenic impact on earth systems predates the terminal Pleistocene and has grown as populations increased and humans have become more widespread. Moreover, owing to the disproportionate influence on ecosystem structure and function of megafauna, past and present body size downgrading has reshaped Earth\u27s biosphere. Thus, macroecological studies based only on modern species yield distorted results, which are not representative of the patterns present for most of mammal evolution. Our review supports the concept of benchmarking the “Anthropocene” with the earliest activities of Homo sapiens

Taxonomy Genetics

New rodent species described since 2000; an age of discovery, comments and prospects Guillermo D'Elia Molecular phylogeny and distribution of the most widespread African rodents, the multimammate mice genus Mastomys: a review Alexandra Hánová, Adam Konečný, Ondřej Mikula, Leonid A. Lavrenchenko, Alex Martynov, Radim Šumbera, Josef Bryja Molecular evolution, hybridization and introgression affect molecular systematics of old world mice Eslam ElShahat, Michael H. Kohn Genetic structure and morphological evolution of the house mouse on the Orkney Archipelago Pascale Chevret, Orkney field team, Guila Ganem, Sabrina Renaud Genetic differentiation and phylogeographic structure of the house mouse Mus musculus s.str. in the northern Palearctic Aleksey Maltsev, Elena Kotenkova, Alexey S. Bogdanov, Valery Stakheev, Yriy Bazhenov Taxonomic structure and evolutionary history of mountain voles (Alticola, subgenus Aschizomys) in north-eastern Asia Semyon Yu. Bodrov, Evgeny Genelt-Janovsky, Evgeny S. Zakharov, Veronika K. Vasilyeva, Innokentiy M. Okhlopkov, Nataliya Abramson Multiple mitochondrial pseudogenes in the nuclear genome in two species of mole voles (Ellobius, Cricetidae) Kristina V. Kuprina, Olga V. Bondareva, Antonina V. Smorkatcheva, Nataliya Abramson, Svetlana A. Galkina Comparative study of striped field mouse Apodemus agrarius from continental and insular populations: the result of five microsatellite loci analysis Liubov V. Frisman, Irina N. Sheremetyeva, Irina V. Kartavtseva, Marina V. Pavlenko, Alexey S. Bogdanov Phylogeography, taxonomy and diversity of montane populations of laminate-toothed rats (Muridae: Otomys) in the southern Great Escarpment, South Africa, with the description of a new species Peter J. Taylor,, Teresa Kearney,, Desirée L. Dalton,, Gamuchirai Chakona,, Chris M. R. Kelly,, Nigel P. Barker Computational species delimitation provides evidence for distinct evolutionary lineages of Trinomys iheringi (Rodentia: Echomyidae) Camila L. Nacif, Beatriz M. Carvalho, Cibele R. Bonvicino Genetic analysis of type material brings logical order in geographic distribution and taxonomy. Case study of Central Asian vole genera Neodon, Blanfordimus, Lasiopodomys Nataliya Abramson, Tatyana Petrova The genus Sciurus in Turkey: data on their distribution, morphometry, karyology and mtDNA sequence variation Şakir Önder Özkurt, İrfan Kandemir A new vole record from Anatolia may change the evolutionary story of voles in Anatolia Sercan Irmak, Mustafa Sözen, Ortaç Çetintaş, Muhsin Çoğal, Ferhat MaturNew rodent species described since 2000; an age of discovery, comments and prospects Guillermo D'Elia Molecular phylogeny and distribution of the most widespread African rodents, the multimammate mice genus Mastomys: a review Alexandra Hánová, Adam Konečný, Ondřej Mikula, Leonid A. Lavrenchenko, Alex Martynov, Radim Šumbera, Josef Bryja Molecular evolution, hybridization and introgression affect molecular systematics of old world mice Eslam ElShahat, Michael H. Kohn Genetic structure and morphological evolution of the house mouse on the Orkney Archipelago Pascale Chevret, Orkney field team, Guila Ganem, Sabrina Renaud Genetic differentiation and phylogeographic structure of the house mouse Mus musculus s.str. in the northern Palearctic Aleksey Maltsev, Elena Kotenkova, Alexey S. Bogdanov, Valery Stakheev, Yriy Bazhenov Taxonomic structure and evolutionary history of mountain voles (Alticola, subgenus Aschizomys) in north-eastern Asia Semyon Yu. Bodrov, Evgeny Genelt-Janovsky, Evgeny S. Zakharov, Veronika K. Vasilyeva, Innokentiy M. Okhlopkov, Nataliya Abramson Multiple mitochondrial pseudogenes in the nuclear genome in two species of mole voles (Ellobius, Cricetidae) Kristina V. Kuprina, Olga V. Bondareva, Antonina V. Smorkatcheva, Nataliya Abramson, Svetlana A. Galkina Comparative study of striped field mouse Apodemus agrarius from continental and insular populations: the result of five microsatellite loci analysis Liubov V. Frisman, Irina N. Sheremetyeva, Irina V. Kartavtseva, Marina V. Pavlenko, Alexey S. Bogdanov Phylogeography, taxonomy and diversity of montane populations of laminate-toothed rats (Muridae: Otomys) in the southern Great Escarpment, South Africa, with the description of a new species Peter J. Taylor,, Teresa Kearney,, Desirée L. Dalton,, Gamuchirai Chakona,, Chris M. R. Kelly,, Nigel P. Barker Computational species delimitation provides evidence for distinct evolutionary lineages of Trinomys iheringi (Rodentia: Echomyidae) Camila L. Nacif, Beatriz M. Carvalho, Cibele R. Bonvicino Genetic analysis of type material brings logical order in geographic distribution and taxonomy. Case study of Central Asian vole genera Neodon, Blanfordimus, Lasiopodomys Nataliya Abramson, Tatyana Petrova The genus Sciurus in Turkey: data on their distribution, morphometry, karyology and mtDNA sequence variation Şakir Önder Özkurt, İrfan Kandemir A new vole record from Anatolia may change the evolutionary story of voles in Anatolia Sercan Irmak, Mustafa Sözen, Ortaç Çetintaş, Muhsin Çoğal, Ferhat Matu