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71.
两种鼠耳蝠回声定位叫声的比较 总被引:7,自引:3,他引:4
对鼠耳蝠属两种蝙蝠飞行状态下的声发射进行了比较研究.结果表明两种鼠耳蝠声发射信号的声谱图都呈调频(FM)型,但在波形及频率范围上有明显差异.大鼠耳蝠(四川亚种)的声脉冲宽度很小(1.6±0.3ms),能率环较低(4.0%),其主频率(DF=44.6±4.3kHz)也较低;而水鼠耳蝠的声脉冲宽度较大(4.2±1.6ms),能率环(9.6%)及主频率(DF=83.0±4.0kHz)也较高.文中结合两种蝙蝠的形态及食性分析了回声定位对捕食生境及捕食策略的适应性. 相似文献
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Host and parasite life history interplay to yield divergent population genetic structures in two ectoparasites living on the same bat species 下载免费PDF全文
Host–parasite interactions are ubiquitous in nature. However, how parasite population genetic structure is shaped by the interaction between host and parasite life history remains understudied. Studies comparing multiple parasites infecting a single host can be used to investigate how different parasite life history traits interplay with host behaviour and life history. In this study, we used 10 newly developed microsatellite loci to investigate the genetic structure of a parasitic bat fly (Basilia nana). Its host, the Bechstein's bat (Myotis bechsteinii), has a social system and roosting behaviour that restrict opportunities for parasite transmission. We compared fly genetic structure to that of the host and another parasite, the wing‐mite, Spinturnix bechsteini. We found little spatial or temporal genetic structure in B. nana, suggesting a large, stable population with frequent genetic exchange between fly populations from different bat colonies. This contrasts sharply with the genetic structure of the wing‐mite, which is highly substructured between the same bat colonies as well as temporally unstable. Our results suggest that although host and parasite life history interact to yield similar transmission patterns in both parasite species, the level of gene flow and eventual spatiotemporal genetic stability is differentially affected. This can be explained by the differences in generation time and winter survival between the flies and wing‐mites. Our study thus exemplifies that the population genetic structure of parasites on a single host can vary strongly as a result of how their individual life history characteristics interact with host behaviour and life history traits. 相似文献
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- 1 Studies of habitat use in which the individual animal is the sampling unit should ideally sample each individual sufficiently to achieve a stable estimate of its habitat use. Data are typically obtained by radio-tracking, which can be labour-intensive. Hence, optimization of sampling effort is desirable. A method to determine optimum sampling effort is described with reference to an example from a study of Natterer's bat Myotis nattereri, in which data were collected by radio-tracking with individual bats followed continuously for entire nights.
- 2 Habitat use by Natterer's bat was assessed by compositional analysis, which compares the composition of habitats used with those potentially available. Therefore, we plotted running per cent foraging time spent over a range of habitat types against the cumulative foraging time recorded. We visually estimated the optimum sum of foraging time required to determine stable estimates of the composition of habitat use from the plots. Then, by reference to the full-time budget, the total tracking effort expended at the point when this optimum amount of foraging data had been recorded was determined and expressed in units of the number of nightly tracking sessions that had been undertaken to collect that amount of foraging data.
- 3 Stable estimates of habitat use were attained after a mean of 22 ± 7.7 h of foraging time, which were obtained in a mean of 4.6 ± 1.9 nights of radio-tracking effort. Thus, in this Natterer's bat study, where habitat preference was assessed by compositional analysis, it was appropriate to aim to collect foraging data during five nights of radio-tracking for each bat sampled.
- 4 The method presented is also applicable to studies where tracking data are discontinuous. A variation of the method can be applied in studies where a Euclidean distance method is to be used for the analysis of habitat use.
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Eero J. Vesterinen Lasse Ruokolainen Niklas Wahlberg Carlos Peña Tomas Roslin Veronika N. Laine Ville Vasko Ilari E. Sääksjärvi Kai Norrdahl Thomas M. Lilley 《Molecular ecology》2016,25(7):1581-1594
Optimal foraging theory predicts that predators are selective when faced with abundant prey, but become less picky when prey gets sparse. Insectivorous bats in temperate regions are faced with the challenge of building up fat reserves vital for hibernation during a period of decreasing arthropod abundances. According to optimal foraging theory, prehibernating bats should adopt a less selective feeding behaviour – yet empirical studies have revealed many apparently generalized species to be composed of specialist individuals. Targeting the diet of the bat Myotis daubentonii, we used a combination of molecular techniques to test for seasonal changes in prey selectivity and individual‐level variation in prey preferences. DNA metabarcoding was used to characterize both the prey contents of bat droppings and the insect community available as prey. To test for dietary differences among M. daubentonii individuals, we used ten microsatellite loci to assign droppings to individual bats. The comparison between consumed and available prey revealed a preference for certain prey items regardless of availability. Nonbiting midges (Chironomidae) remained the most highly consumed prey at all times, despite a significant increase in the availability of black flies (Simuliidae) towards the end of the season. The bats sampled showed no evidence of individual specialization in dietary preferences. Overall, our approach offers little support for optimal foraging theory. Thus, it shows how novel combinations of genetic markers can be used to test general theory, targeting patterns at both the level of prey communities and individual predators. 相似文献
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2013年4月在湖北省十堰市房县野人洞(31°55'8.3″N,110°43'56.5″E,海拔282 m)捕捉到11号鼠耳蝠标本(5雄6雌),同时在江苏省宜兴市灵谷洞(31°13'20.9″N,119°44'23.3″E,海拔123 m)捕捉到5号鼠耳蝠标本(1雄4雌)。上述鼠耳蝠标本体型较小,前臂长33.6~37.5 mm,颅全长11.2~13.8 mm;后足长不及胫骨长之半;背毛基部黑色,毛尖棕色有时更多显现浅红灰色,腹毛基部黑色但毛尖淡灰白;上颌前臼齿(P3)位于齿列之中。经鉴定均为尼泊尔鼠耳蝠(Myotis nipalensis),分别为湖北省和江苏省翼手目新纪录。本文给出了尼泊尔鼠耳蝠的外形和头骨特征及其相关测量数据,并与来自青海、尼泊尔的标本进行了对比;同时对其回声定位信号进行室内录制及分析;此外对其分类地位和分布状况进行了讨论。标本保存于广东省昆虫研究所。 相似文献
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Aim Three mechanisms have been proposed to explain the adaptive radiations and species diversifications of Madagascar’s biota: the ecogeographical constraint, the riverine barrier and the micro‐endemism models. On the intraspecific level, each model predicts different patterns of gene flow across the island’s physical and ecological features. To evaluate these models, phylogeographical analyses were conducted on a widespread and endemic species of bat, Myotis goudoti (Vespertilionidae). Location Madagascar. Methods In order to reconstruct the phylogeographical history of M. goudoti, the mitochondrial D‐loop and the cytochrome b gene were sequenced for 195 bats from 41 localities. Phylogenetic reconstructions and a minimum spanning tree were used to infer haplotype relationships. The effect of barriers on gene flow was evaluated using analyses of molecular variance and pairwise population differentiation. Mismatch distribution and coalescence‐based estimates were conducted to infer the demographic history of M. goudoti. Results The sequenced individuals showed 159 distinct D‐loop haplotypes, most of them being unique to a single location. Populations were significantly structured (ΦST = 0.170, P < 0.001) across Madagascar, but only a minor part of the overall genetic variance was explained by any of the three models. Shared ancestry of lineages across most physical or ecological barriers was common, whereas the uncovered genetic differences between southern and central‐northern populations were unexpected. Main conclusions Major barriers predicted by the three biogeographical models do not explain the segregation of mitochondrial lineages of M. goudoti across Madagascar. This is not simply attributable to the high dispersal ability of this species, as populations are notably structured. The genetic contrast between southern and central‐northern populations, separated by a zone of admixture, suggests that these areas currently support populations that expanded during the Late Pleistocene. This latitudinal differentiation of populations has been observed in less vagile animals, such as geckos and lemurs, suggesting that climate fluctuations of the Pleistocene had an impact across several groups and resulted in northern and southern refugia in Madagascar. 相似文献
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2010年4月16日,在陕西省安康市镇坪县一岩洞内(31°44.888’N,109°22.736’E,海拔1290m)采获1号雄性蝙蝠标本,经鉴定为西南鼠耳蝠Myotis altarium,属陕西省翼手类新纪录,标本保存于陕西省动物研究所标本室。本文对西南鼠耳蝠的形态特征和相关测量数据进行了报道,并对其分布和保护现状进行了简要分析。 相似文献