984 resultados para vampire bat


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[EU]Lan honen helburua, ikuspuntu teoriko eta praktiko batetik ner group erakundea eta enpresa familiarra aztertzea da, erakunde honen enpresa familiarretan eta enpresa familiarrak ner groupen daukan eragina zein den ezagutzeko. Honetarako, harreman estilo berria aztertu ondoren, ner groupeko arduradunari elkarrizketa bat egin eta erakundeko bi enpresa familiar aukeratu ondoren, hauei ere elkarrizketak egin dizkiet biak hurbilagotik ezagutzeko, alderatzeko eta aztertzeko. Honela, enpresa familiarretan harreman estilo berria aplikagarria dela frogatu da baina enpresa familiar bakoitzak dituen baldintzak funtsezkoak izango dira estiloaren ezartzean. Era berean, enpresa familiarrentzat ner group erakundean barneratzea abantaila suposatzen diela aztertu da.

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Trabajo desarrollado dentro del proyecto Monumenta Linguae Vasconum III (FFI2008-04516) del MICIN y del GIC: IT-486-10 del GV.

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[EUS] Lan honetan aurkikuntza baten berri ematen dugu: Plentziako armarri batean aurkitutako hiru euskal esaera zahar (1603) aurkezten eta hizkuntzaren eta historiaren ikuspuntutik aztertzen ditugu. Hiru esaerotatik bi «Refranes y sentencias» 1596) lanean agertzen dira, eta hori datu garrantzitsua da; izan ere, Lakarrak 1996) errefrau-bilduma anonimo horren jatorriaz egindako proposamena berresteko argudio berria da. Zehazki, Bizkaiko ipar-mendebala proposatu zuen Lakarrak bildumako errefrauen jatorri gisa. Beste alde batetik, Bizkaiko ipar-mendebaleko euskararen zenbait ezaugarri baliatuta, Arrasateko erreketari buruzko zenbait kantu eremu horretan sortu zirela proposatzen dugu —zehazki, Butroeko (Gatika) dorretxearen inguruan—, hizkuntzari dagozkion argudioak historiari buruzkoekin osatuta.

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Lan honen ikergaia, Europan emandako gatazka bortitzen, eta zehazki armatuen, analisia izango da. Horretarako, gatazka armatu horien eta mobilizazio zikloen artean dauden harremanak eta zubiak aztertzen saiatuko gara. Analisi hau, 1960 hamarkadaren bukaeran eta 1970 hamarkadaren hasieran zentratuko da, izan ere, denbora tarte horretan eman ziren gatazka bortitzen espresiorik nagusienak, gatazka armatuak alegia. Hori aztertzeko, 4 kasu hartuko dira: ETA Euskal Herrian, IRA Irlandan, Brigate Rosse Italian eta Rote Armee Fraktion Alemanian.

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The Vespertilionidae is the largest family in the order Chiroptera and has a worldwide distribution in the temperate and tropical regions. In order to further clarify the karyotype relationships at the lower taxonomic level in Vespertilionidae, genome-wid

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Bats (Chiroptera) are the second-most abundant mammalian order in the world, occupying a diverse range of habitats and exhibiting many different life history traits. In order to contribute to this highly underrepresented group we describe the sleep architecture of two species of frugivorous bat, the greater short-nosed fruit bat (Cynopterus sphinx) and the lesser dawn fruit bat (Eonycteris spelaea). Electroencephalogram (EEG) and electromyogram (EMG) data were recorded from multiple individuals (>= 5) by telemetry over a 72-h period in a laboratory setting with light/dark cycles equivalent to those found in the wild. Our results show that over a 24-h period both species spent more time asleep than awake (mean 15 h), less than previous reported for Chiroptera (20 h). C sphinx spent significantly more of its non-rapid eye movement sleep (NREM) and rapid eye movement sleep (REM) quotas during the light phase, while E. spelaea divided its sleep-wake architecture equally between both light and dark phases. Comparing the sleep patterns of the two species found that C. sphinx had significantly fewer NREM and REM episodes than E. spelaea but each episode lasted for a significantly longer period of time. Potential hypotheses to explain the differences in the sleep architecture of C. sphinx with E. spelaea, including risk of predation and social interaction are discussed. (C) 2010 Published by Elsevier B.V.

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Bamboo bats are a group of small bats with unique skull and morphology. They roost inside hollow bamboo stems in tropical and subtropical Asia and the Ambon Islands (Moluccas). We examined 53 specimens of Tylonycteris from southern and southwestern China. Comparisons of skull and external characteristics, pelage color, shapes of thumbpads and footpads, and statistical analysis of cranial measurements revealed that specimens from Damenglong, Jinghong County, Xishuang-banna, Yunnan, are distinctly different from the other two species of Tylonycteris described so far. The Yunnan specimens are the smallest in size; have dark blackish brown pelage color; and have larger upper premolars, smaller first lower premolars, and longer C-M-3. They are sympatric with the previously described species. Here we review the genus Tylonycteri and describe a new species, Tylonycteris pygmaeus, from the Yunnan material.

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本文研究了栖息在高寒地区的高原鼠兔(Ochotona curzoniae)的体温、热代谢和肩胛部BAT随个体发育的变化,讨论了高原鼠兔热代谢发育特征及发育策略。结果表明新生个体具有初步的热调节能力,但环境温度变化时,还不能维持稳定的体温。体重为12.5克的幼体(约1-3日龄),其最低代谢离为3.028(mlO_2/g·h),相对于Kleiber期望值的百分率为167%,热传导率为0.518(mlO_2/g·h· ℃),相对于Bradley-Deavers期望值的百分率为200%,热中性区下临界温度为32.7 ℃。随着个体的发育,最低代谢率趋于下降,但其相对于Kleiber期望值的百分率在体重增长到大约90克前,趋于增加,其后才略有下降,热传导率及其相对于Bradley-Deavers期望值的百分率和热中性区的下临界温度随个体的发育趋于降低。所以在各环境温度下,高原鼠兔的体温随着个体发育表现出上升的变化。高原鼠兔BAT在整个发育时期都存在。刚出生时BAT发达,相对重量高,结构成熟,BAT细胞充满小而多的脂肪滴,线粒分布致密。随着个体发育,BAT相对重量和水分含量均迅速降低,结构呈退化趋势。高原鼠兔幼体主要利用小气候环境和BAT产热抵抗低温压力,高原鼠兔热调节发育的特征和对小气候环境的利用有利于减少体温调节耗能,促进生长发育。而发育到成体时,最低代谢率和热传导率对其期望值的偏离反映出高原鼠兔对西息环境的适应。另外,高原鼠兔通过行为热调节对生理调节加以补充。

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Eleven polymorphic microsatellite marker loci were developed from a Leisler's bat (Nyctalus leisleri) genomic enriched library. Assessment of the usefulness of these markers for population genetics studies of Leisler's bats was carried out by screening 100 specimens sampled from eight locations in Ireland and two in Northeastern France. Both moderately and highly polymorphic marker loci were identified. Five to 28 alleles were found to be segregating per locus with observed heterozygosities values ranging from 28.4 to 94%. Initial evaluation indicates that these microsatellites will be useful for genetic based studies aiming, for instance, at parentage and population structure of Leisler's bats.

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Aim To examine the effect of climate change on the occurrence and distribution of Pipistrellus nathusii (Nathusius' pipistrelle) in the United Kingdom (UK).Location We modelled habitat and climatic associations of P. nathusii in the UK and applied this model to the species' historical range in continental Europe.Methods A binomial logistic regression model was constructed relating the occurrence of P. nathusii to climate and habitat characteristics using historical species occurrence records (1940-2006) and CORINE land cover data. This model was applied to historical and projected climate data to examine changes in suitable range (1940-2080) of this species. We tested the predictive ability of the model with known records in the UK after 2006 and applied the model to the species' known range in Europe.Results The distribution of P. nathusii was related positively to the area of water bodies, woodland and small areas of urbanization, and negatively related to the area of peat/heathland. Species records were associated with higher minimum temperatures, low seasonal variation in temperature and intermediate rainfall. We found that suitable areas have existed in the UK since the 1940s and that these have expanded. The model had high predictive power when applied to new records after 2006, with a correct classification rate of 70%, estimated by receiver operating characteristic analysis. Based on climate projections, our model suggests a potential twofold increase in the area suitable for P. nathusii in the UK by 2050. The single most influential climate variable contributing to range increase was the projected increase in minimum temperature. When applied to Europe, the model predictions had best predictive capability of known records in western areas of the species' range, where P. nathusii is present during the winter.Main conclusions We show that a mobile, migratory species has adapted its range in response to recent climate change on a continental scale. We believe this may be the first study to demonstrate a case of range change linked to contemporary climate change in a mammal species in Europe.

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The recent identification of Myotis brandtii in Ireland raised the possibility that many roosts previously identified as M. mystacinus had the potential of being misidentified M. brandtii. Thus, the distribution and population estimates for M. mystacinus may have been over-estimated, while M. brandtii may have been under-estimated. Results from an all Ireland genetic survey of known M. mystacinus maternity roosts confirm that no long term misidentification has taken place. All specimens caught and sampled were M. mystacinus. Additonally, no further records of M. brandtii were found during six nights of woodland trapping using the acoustic lure. While the status of M. mystacinus in Ireland is now listed as ‘least concern’ in the Irish Red List, M. brandtii is listed as ‘data deficient’ and cannot currently be considered a resident species

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Recent evidence suggests that bats can detect the geomagnetic field, but the way in which this is used by them for navigation to a home roost remains unresolved. The geomagnetic field may be used by animals both to indicate direction and to locate position. In birds, directional information appears to be derived from an interaction of the magnetic field with either the sun or the stars, with some evidence suggesting that sunset/sunrise provides the primary directional reference by which a magnetic compass is calibrated daily. We demonstrate that homing greater mouse-eared bats (Myotis myotis) calibrate a magnetic compass with sunset cues by testing their homing response after exposure to an altered magnetic field at and after sunset. Magnetic manipulation at sunset resulted in a counterclockwise shift in orientation compared with controls, consistent with sunset calibration of the magnetic field, whereas magnetic manipulation after sunset resulted in no change in orientation. Unlike in birds, however, the pattern of polarization was not necessary for the calibration. For animals that occupy ecological niches where the sunset is rarely observed, this is a surprising finding. Yet it may indicate the primacy of the sun as an absolute geographical reference not only for birds but also within other vertebrate taxa.

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Much is known about the way bats adjust their echolocation behaviour in response to environmental structure or to locate insect prey. By contrast, little is known about how echolocation calls are modulated in response to familiarity of the environment and objects within it. Here we show that the echolocating Megachiropteran bat Rousettus aegyptiacus produces echolocation signals at the same rate whether an obstacle is predictable or unpredictable in location, but that it has a reduced rate of echolocation signal production in a familiar environment with no obstacle present. This suggests that signal production is reduced in a familiar environment absent of 'clutter' but that probing the environment for maximum information is more important for this species than minimizing any cost of probing the environment in a cluttered space.