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1.
In a one-year study on the diet of the Long-eared Owl, Asio otus, in the area of Karap?nar in Central Anatolia, 5324 prey items were recovered from 3314 pellets collected at monthly intervals. At least 7 species of mammals belonging to Insectivora (Crocidura suaveolens) and Rodentia (Allactaga williamsi, Cricetulus migratorius, Meriones tristrami, Mescocricetus brandti, Microtus guentheri, M. sp., Mus macedonicus) were identified. Rodentia were dominant and contributed 93.8% of the number of prey items of the Long-eared Owl. Microtus guentheri accounted for 83.9% of the rodent remains. The diet pattern was more diverse in summer, when some 24% of the diet consisted of non-mammal prey items (birds, insects).  相似文献   

2.
Summary The DNA sequence was determined for the cytochrome c oxidase II (COII), tRNALys, and ATPase 8 genes from the mitochondrial genome of the meadow vole, Microtus pennsylvanicus. When compared to other rodents, three different patterns of evolutionary divergence were found. Nucleotide variation in tRNALys is concentrated in the TC loop. Nucleotide variation in the COII gene in three genera of rodents (Microtus, Mus, Rattus) consists predominantly of transitions in the third base positions of codons. The predicted amino acid sequence in highly conserved (>92% similarity). Analysis of the ATPase 8 gene among four genera (Microtus, Cricetulus, Mus, Rattus) revealed more detectable transversions than transitions, many fixed first and second position mutations, and considerable amino acid divergence. The rate of nucleotide substitution at nonsynonymous sites in the ATPase 8 gene is 10 times the rate in the COII gene. In contrast, the estimated absolute mutation rate as determined by analysis of nucleotide substitutions at fourfold degenerate sites probably is the same for the two genes. The primary sequences of the ATPase 8 and COII peptides are constrained differently, but each peptide is conserved in terms of predicted secondary-level configuration.  相似文献   

3.
This study deals with the «percrocutoid hyaenids,present in Eurasia and in Africa in faunas of late Middle Miocene (Astaracian) to terminal Miocene (Vallesian, Turolian) age. These hyaenid species are characterized by certain dental apomorphies (loss of M2/2, specialization of the carnassials P4/M1, tendency for the hypertrophy of the anterior premolars) which differentiate them from other hyaenids with which they are found associated. In recent literature, these hyaenids have been attributed to the genera PercrocutaKretzoi and AdcrocutaKretzoi, the latter of which is monospecific. In fact some should be removed from the genus Percrocuta and assigned to the genus AllohyaenaKretzoi, itself subdivided into the two subgenera, AllohyaenaKretzoi and DinocrocutaSchmidt-Kittler. The genus Adcrocuta is retained and the characters which distinguish this genus from HyaenictisGaudry are discussed.This study is based on revision of all, or nearly allsuch specimens, described and figured or in collections, of which certain among them have been hardly or poorly known. Particular attention has been given to their geologic age and their distribution in Neogene mammalian faunas (Mein's zones). Their apomorphies, considered in relation to their temporal distributions, permit an interpretation of the phylogenetic relationships of their several lineages which is consistant with the proposed systematic revision of the group.The radiation of «percrocutoid hyaenids would appear to have occurred in three phases. At the beginning of the Astaracian, after the dispersal of Anchitherium, the genus Percrocuta appeared with several species of relatively small size; in Eurasia this genus does not seem to have persisted after the middle Astaracian, although it did so in the sub-Himalayan Siwaliks. At the end of the Astaracian it was apparently succeeded by the genus Allohyaena, and resulting in gigantic forms (subgenus Dinocrocuta) coincident in Eurasia and in Africa with the extension of Hipparion. The third phase of the radiation is represented by the genus Adcrocuta, which unlike the others, was monospecific. This single species, A. eximia, occurs initially, and very rarely in the upper Vallesian; however, in the middle Turolian it is common and widespread throughout Eurasia where it, perhaps, limited the expansion of Dinocrocuta.  相似文献   

4.
We developed nine polymorphic microsatellite loci for the field vole, Microtus agrestis. The number of alleles ranged from five to 15 and observed heterozygosities ranged from 0.40 to 1.00. We also tested the microsatellite loci for amplification and polymorphism in the congeneric species Microtus arvalis. Five of the nine loci were successfully analysed in this species. The microsatellite markers will be employed in studies of reproductive success and fine‐scale spatial genetic structure.  相似文献   

5.
The present article extends our previous work on the phylogenetic history of Microtus (Terricola) thomasi, analysing cytochrome b, 12S rRNA, 16S rRNA and the control region in 65 Greek populations. The analysis revealed three clades: one grouping the populations from Peloponnisos (Southern Greece); the second, the populations from Agios (Ag.) Stefanos and Evvoia island (Central East Greece); and the third, all the remaining populations with no geographical substructure. Genetic distances were low for most populations, with only the populations of Evvoia and Ag. Stefanos being substantially distant. Thus, although this species has a recent colonization history and probably descends from a highly polymorphic ancestor, a monophyletic and highly differentiated lineage is formed in Greece and is distributed in Ag. Stefanos and Evvoia. Molecular differentiation, distinct geographical distribution and restriction of gene flow between this lineage and the rest of the Greek populations provide evidence for its probable subspecific status, Microtus (Tericola) thomasi atticus. A possible mechanism leading the differentiation process of the proposed subspecies is suggested, based on the displacement of this species in central Greece by its congeneric, probably better‐fitted Microtus (Microtus) guentheri and the subsequent separation of Ag. Stefanos and Evvoia from the remaining Greek populations. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 95 , 117–130.  相似文献   

6.
Small mammal populations were studied during a 10 year multi-annual fluctuation of vole populations in marshes and adjacent grassland of the basin in the Jura mountains, France. Nine species were monitored:Microtus agrestis, Clethrionomys glareolus, Apodemus flavicollis, Sorex araneus Icoronatus, Neomys fodiens, Crocidura leucodon, Mustela nivalis in marshes andArvicola terrestris andMicrotus arvalis in grassland, using live-trapping and index methods during July from 1993 to 2002. Populations of A.terrestris, M. arvalis, M. agrestis, S. araneus I coronatus andM. nivalis exhibited a relatively strong inter-specific temporal synchrony in their multi-annual fluctuations.C. glareolus population fluctuations were not synchronous to theArvicola I Microtus I Sorex group, and were closer to those ofApodemus flavicollis, Neomys andCrocidura. Those results are discussed in the light of earlier studies carried out in the same region and in northern ecosystems.  相似文献   

7.
8.
9.
Inheritance of 15 polymorphic isozymes was investigated in captive Microtus californicus. Eleven of the isozymes show patterns consistent with a Mendelian model of inheritance: glycerol-3-phosphate dehydrogenase (GPD), lactate dehydrogenases A and B (LDH-A and LDH-B), malic enzyme 2 (ME-2), isocitrate dehydrogenase 1 (ICD-1), phosphogluconate dehydrogenase (PGD), glutamate-oxaloacetate transaminase 1 (GOT-1) phosphoglucomutase 2 (PGM-2), leucine aminopeptidase (LAP), glucosephosphate isomerase (GPI), and esterase 2 (ES-2, from kidney). four of the isozymes show patterns that cannot be interpreted by a simple genetic model: esterases 1 and 4 (ES-1, ES-4, from hemolysate), esterase 3 (ES-3, from plasma), and protein 1 (PT-1). The following pairs of loci are assorting independently: LAP and PGD, LAP and PGM-2, GOT-1 and PGD, GOT-1 and GPD, LAP and GPD, GPD and PGD, GPI and PGD. Data from one test cross mating indicate that GPD and PGM-2 are loosely linked with recombination about 30%. Additional data are needed to confirm this relationship.This study was conducted while the first author was the recipient of an NIH Traineeship. The Departments of Genetics and Zoology provided financial support for the maintenance of the animal colony. This work was supported in part by an NIH-Biomed grant (3-S05-RR-07006-08S1) to W. Z. Lidicker.  相似文献   

10.
Abstract: A systematic revision of the sabre‐toothed cat genus Paramachaerodus  Pilgrim, 1913 is presented. Two species are recognized within Paramachaerodus, Pa. orientalis, and Pa. maximiliani, and the genus Promegantereon  Kretzoi, 1938 is retrieved to include Promegantereon ogygia. Material from the Turolian Spanish localities of Crevillente‐2 (MN 11, Alicante) and Las Casiones (MN 13, Teruel), which was previously assigned to Paramachaerodus, is now included in the tribe Metailurini. The exceptional discoveries at the Spanish Vallesian (MN 10, Madrid) fossil site of Batallones‐1 have made it possible to characterize the dentition and cranial anatomy of a previously very poorly known machairodontine cat, formerly included in Paramachaerodus as Pa. ogygia, which now can be distinguished from Pa. orientalis and Pa. maximiliani by the following features: canines without crenulations, P3 with a marked disto‐lingual expansion, P4 without ectostyle and with a well‐developed protocone, M1 bucco‐lingually elongated and double‐rooted, m1 with a larger talonid, and primitive mandible morphology. Thus, the population from Batallones‐1 constitutes a clearly different form from the genus Paramachaerodus, and we propose its inclusion in the genus Promegantereon  Kretzoi, 1938 , together with an upper canine from Crevillente‐2 (MN 11), very similar to those from Batallones‐1. In contrast, Pa. orientalis shows the following apomorphies: crenulated canines, P3 reduced in size and without disto‐lingual expansion, P4 with a clear ectostyle as well as a reduced, backwardly displaced protocone and with a rounded and single‐rooted M1. The species Pa. maximiliani is characterized by its slightly larger size, crenulated canines, very elongated P3 with a moderate disto‐lingual expansion and P4 and M1 similar to those of Pa. orientalis. Paramachaerodus orientalis is recorded at Puente Minero (MN 11, Teruel), Concud (MN 12, Teruel), Crevillente‐15, and Crevillente‐16 (both MN 12, Alicante), and Paramachaerodus maximiliani in Venta del Moro (MN 13, Valencia). The available data suggest that Pr. ogygia was present in the Iberian Late Vallesian and Early Turolian faunas (MN 10 and MN 11) but disappeared after that age. Paramachaerodus was present in the faunas throughout the Turolian, with the species Pa. orientalis and Pa. maximiliani, this latter being probably part of the same immigration event that occurred in the Late Turolian and involved other mammal taxa such as camelids and ursids.  相似文献   

11.
The presence of a large hyaenoid (Hiperhyaena sic leakeyi) from the Late Miocene (Vallesian equivalent) deposits at Nakali, Kenya, was first recorded in 1974, but the fossil on which the announcement was based was not described or figured, nor was a type specimen or type species nominated. The generic and specific names are thus nomina nuda. Howell and Petter (1985) described Hyperhyaena leakeyi, and credited the generic and specific names alternatively to Aguirre and Leakey (1974) and Aguirre and Crusafont in 1974 (the latter paper was never published). Howell and Petter are in fact the authors of both the generic and the specific names. Later in the same paper, Howell and Petter (1985) rejected the name Hyperhyaena and classified the species leakeyi in Allohyaena (Dinocrocuta). The purpose of this paper is to provide more information about the fossil and to discuss its relationships to other percrocutids. It is concluded that it belongs to the genus Percrocuta Kretzoi, 1938, being morphologically similar to the type species Percrocuta carnifex (Pilgrim, 1913) from the Siwaliks of Pakistan.  相似文献   

12.
13.
The botanical composition and the ratio of various plants in the diet of Microtus socialisPall. were determined by microhistological cuticular-coprological analysis of undigested remains. Microtus socialis disappeared from the zonal plain of the Volga-Ural interfluve in the early 1970s and appeared again in 2009. The role of grains in their nutrition became more important, and the ratio of wormwoods sharply decreased. The feeding patterns observed are caused by the long-term absence of these massive phytophages and reflect significant changes in the habitat over the last 40 years.  相似文献   

14.
Zusammenfassung Das Enzym 6-PGD zeigt bei den verschiedensten Species einen genetisch gesteuerten Polymorphismus, der sich bei elektrophoretischer Darstellung in einer Variabilität des Isoenzymmusters äußert. Die Befunde bei den bislang untersuchten Säugern unter Einschluß des Menschen lassen sich formalgenetisch nach dem Modell: 1 Genlocus mit multipler Allelie interpretieren. Zur Prüfung der Frage, ob das Säugergenom einheitlich nur ein Gen für dieses Enzym enthält oder ob bei einzelnen Species eine Duplikation dieses Gens existiert, wurdene eine Anzahl Säuger verschiedener Ordnungen untersucht. In einer ersten Mitteilung wird hier über 6 verschiedene Species der Microtinae berichtet. Die Befunde sprechen durchweg für die Existenz von jeweils nur 1 Genlocus der 6-PGD. Bei Microtus oeconomus wurden 2 Allele an diesem locus nachgewiesen, bei Microtus ochrogaster 3 verschiedene Allele. Durch Familienuntersuchungen bei diesen beiden Species werden alle möglichen Kombinationen dieser Allele nachgewiesen.
The genetics of 6-PGD (EC: 1.1.1.44) in various mammals I. Studies on 6 species of Microtinae, Rodentia. Isoenzyme polymorphism and family studies in Microtus oeconomus and Microtus ochrogaster
Summary The enzyme 6-PGD exhibits a genetically determined polymorphism which results in a variability of the isoenzyme pattern. In mammals so far examined the findings are to be interpreted according to the model of multiple alleles at one single gene locus. In order to test whether the mammalian genome is uniformly endowed with one single locus for this enzyme or whether a duplication of this locus is present in certain species, we examined various mammals of different orders. Our results in this first communication on 6 different Microtinae species are all in agreement with the assumption of a single 6-PGD locus. In Microtus oeconomus 2 alleles could be demonstrated and in Microtus ochrogaster 3 different alleles. Family studies performed with both species revealed the occurrence of all the expected combinations of these alleles.
  相似文献   

15.
Lamar Cave, a late Holocene paleontological site in Yellowstone National Park, USA, has yielded 36 fossil mammal species from 10 stratigraphic units representing about 2000 years. The fossil fauna is similar to the mammals in the park today and affords a unique opportunity to investigate paleocommunity and ecosystem dynamics through time.

Remains of an extralimital species in Yellowstone today, Microtus ochrogaster are found only in the oldest cave deposits, dated at 1695 ± 60 yr B.P. Disappearance of this species by about 1550 years ago marks evolution into the ecosystem that has persisted into the present and is recognizable by a fossil mammal assemblage that is virtually identical to the modern one. Relative abundance fluctuations in the mammal populations imply community resilience through the past 2000 years. Trends in relative abundances of small mammals, particularly the inverse relationship between Microtus and Spermophilus are interpreted as evidence of declining grass cover near Lamar Cave between approximately 1500 and 1000 years ago. The initiation of this environmental change may well have stimulated the ecosystem change marked by Microtus ochrogaster extirpation. Support for this hypothesis is found in a pollen record from a nearby lake.  相似文献   

16.
T. C. Hsu  S. Pathak 《Chromosoma》1976,58(3):269-273
In two rodent species, the Chinese hamster and the montane vole (Microtus montanus), the rate of sister chromatid exchange was lower in constitutive heterochromatin than in euchromatin.  相似文献   

17.
We surveyed the natural distribution of Borrelia species associated with Lyme disease in the subalpine forests of Nagano prefecture, Japan, during 1993-94. Tick-derived isolates (n = 112) from Ixodes persulcatus and rodent-derived isolates (n = 55) from Apodemus argenteus, Apodemus speciosus, Eothenomys andersoni, Eothenomys smithii, and Microtus montebelli were classified by rRNA gene restriction fragment length polymorphism analysis (RFLP ribotyping). Ribotype group IV (an intraspecific variant of Borrelia garinii) was predominant among the tick isolates. It was also isolated repeatedly from the rodents. Ribotype group III (Borrelia afzelii) was detected in low frequencies among the tick and rodent isolates. The data suggest that humans are likely to be exposed to the group IV when they are bitten by I. persulcatus ticks.  相似文献   

18.
A comparison of terrestrial small mammal coenoses belonging to nine different biotopes in the tips of the Iberian and Italian peninsulas was carried out using the pitfall trapping method. The influence of both habitat type and peninsular effect on composition of small mammal coenoses was analysed. In Southern Italy, 203 specimens belonging to seven species were trapped: Suncus etruscus (Savi, 1822), Crocidura suaveolens (Pallas, 1811), C. leucodon (Hermann, 1780), Microtus savii (de Sélys-Longchamps, 1838), Apodemus sylvaticus (L., 1758), A. flavicollis (Melchior, 1834) and Mus musculus domesticus Schwarz & Schwarz, 1943. In Southern Spain 428 specimens belonging to five species were trapped: Suncus etruscus, Crocidura russula (Hermann, 1780), Microtus duodecimcostatus (de Sélys-Longchamps, 1839), Apodemus sylvaticus and Mus spretus Lataste, 1883. The relative density of small mammals occurring in the nine Spanish sampling stations was twice that recorded in the Italian stations; however the number of species recorded in the different biotopes show similar mean values, ranging from three to five in Andalusia and from three to six in Calabria. Apodemus sylvaticus was the dominant species in the Calabrian stations, whereas Crocidura russula prevailed in Andalusia. The biotic diversity values are very similar in the Calabrian and Andalusian biotopes. By contrast, the Insectivora/Rodentia ratio was always higher in Andalusia. The more xerophytic biotopes showed greater similarities between the communities in Southern Spain and Southern Italy, while the cooler biotopes differed between these two peninsulas.  相似文献   

19.
Since voles, mice and shrews are important animals in food chains of river floodplains, there is a need for data on their spatial and temporal distribution in periodically flooded areas. During a live trapping study between two successive floods in an embanked river floodplain, the ’Afferdensche en Deestsche Waarden (ADW)’, six species were frequently observed, viz,Microtus arvalis (Pallas, 1778),Clethrionomys glareolus (Schreber, 1780),Sorex araneus (Linnaeus, 1758),Crocidura russula (Hermann, 1780),Micromys minutus (Pallas, 1771) andApodemus sylvaticus (Linnaeus, 1758). Ungrazed rough herbaceous vegetation appeared to be rich in numbers and species, whereas no spoors of small mammals were observed in large parts of the ADW floodplain (eg bare substrates and maize fields). Vegetation structure seemed to be very important in guiding the recolonisation process after flood events. Throughout the year the highest numbers of small mammals were captured on and near the non-flooded elevated parts functioning as refugia during inundation. Poor habitat connectivity, sparseness of non-flooded recolonisation sources and small numbers of survivors led to slow recolonisation. The time between two successive floods (eight months) was not long enough for entire recolonisation of ADW. Small mammal densities at more than 30 m from the non-flooded areas were always lower than in non-flooded areas.  相似文献   

20.
In nuclei of the inactive thyroid gland of Microtus agrestis the constitutive heterochromatin is heteropycnotic and forms large chromocenters. After specific activation of the thyroid gland with thyroid stimulating hormone (TSH), or with the thyrostatic methylthiouracil (MTU), an enlargement of cells and nuclei, a high mitotic activity and a despiralization of the contitutive heterochromatin are observed. The facultative heterochromatin, on the contrary, remains condensed. The structure of the nuclei of the parathyroid gland is not altered by the treatment with TSH or MTU. The findings permit the assumption that constitutive heterochromatin has specific functions, e.g. as a nucleolus organizer, which are blocked in the heteropycnotic state and active in the isopycnotic state.Supported by the Bundesministerium für Bildung und Wissenschaft of the Federal Republic of Germany.  相似文献   

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