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21.
树麻雀代谢率和器官重量在季节驯化中表型的可塑性变化   总被引:1,自引:0,他引:1  
柳劲松  李铭 《动物学报》2006,52(3):469-477
动物能量代谢的生理生态特征与物种的分布和丰富度密切相关,基础代谢率(BMR)是内温动物能量预算的重要组成部分。北温带的小型鸟类,通过增加产热来适应低温环境。增加BMR的基础之一是中心器官(代谢机器)发生明显的变化。本研究中我们测定了树麻雀(Passermontanus)的BMR、体重和各器官的重量,分析了麻雀各器官的季节性变化及与BMR的关系。方差分析表明:麻雀的BMR存在明显的季节性变化,在冬季和秋季较高。麻雀内部器官的变化同样有明显的季节性,冬季和秋季麻雀的肝脏、心脏、肌胃、小肠、直肠和整体消化道的重量,都有明显的增加。相关分析表明:麻雀的BMR与肝脏、心脏和消化道等内部器官存在明显的相关性。我们的结果验证了“中心限制假说”,即麻雀体内存在着与BMR相关的“代谢机器”,中心器官是提高麻雀BMR的基础之一。  相似文献   
22.
Primers for 15 microsatellite loci were developed for Mountain Plover, a species whose distribution and abundance have been reduced drastically in the past 30 years. In a screen of 126 individuals collected from four breeding locales across the species’ range, levels of polymorphism ranged from two to 13 alleles per locus. No two loci were found to be linked, although one locus revealed significant departures from Hardy–Weinberg equilibrium. These microsatellite loci can be used in population genetic studies, ultimately aiding in management efforts for Mountain Plover. Additionally, these markers can potentially be used in studies investigating the mating system of Mountain Plover.  相似文献   
23.
To enable the study of the population genetics of the tree sparrow (Passer montanus), which is distributed in many islands of Japan, nine polymorphic microsatellite loci were isolated from 32 individuals. The number of alleles per locus ranged from 2 to 17, and observed heterozygosities ranged from 0.1250 to 0.9375. In eight of the nine loci, the heterozygosities were not significantly different from those expected from Hardy-Weinberg equilibrium. Cross-species amplification in the russet sparrow (P. rutilans) was successful with all primer sets, which were highly polymorphic, suggesting these markers are useful for the population genetics of genus Passer.  相似文献   
24.
Social influences on food caching in willow tits: a field experiment   总被引:5,自引:1,他引:4  
We studied the food hoarding behavior of willow tits (Parusmontanus), a scatter-hoarding passerine wintering in dominance-structuredflocks. We examined social influences on microhabitat selectionand spatial cache distribution at temporary feeders. Dominantadult males stored food closer to die feeder and at a greaterrate than did subordinates. When alone, the birds stored foodcloser to the feeder than when accompanied by conspecifics.Conifers were preferred over deciduous trees as cache trees.The subordinates cached more in die outer parts of branchesthan dominants. There were no significant differences in dierelative or absolute heights of die caches, nor in the verticalor horizontal hoarding niche breadths between dominants andsubordinates. We experimentally removed die dominants from dieflock for 90 min and recorded the behavior of die remainingsubordinates immediately after die removal. The removal resultedin a decrease in die hoarding distance of die remaining birds,indicating that die presence of dominants directly affecteddie behavior of subordinates and suggesting that kleptopar-asitismby dominants may be prevented by rarhing farther away. Withdie dominants removed, die subordinates cached at a greaterrate than before die removal. The decrease in die hoarding distanceand increase in die hoarding rate were die only significanteffects of die experiment, perhaps suggesting that, during ashort absence of dominants, die subordinates do not benefitfrom changing dieir caching microhabitat They might be excludedfrom those new, possibly safer, microhabitats after die dominantbird rejoins die flock.  相似文献   
25.
麻雀种群数量与环境因素关系研究的某些进展   总被引:3,自引:0,他引:3  
胥执清 《四川动物》2004,23(4):386-390
本文主要对1986年以来国外的麻雀种群数量与环境因素的关系研究作一综述。①[树]麻雀和家麻雀间存在巢穴竞争和重叠,家麻雀有更多的防御行为和数量上占优势。[树]麻雀群体繁殖第一次比单独繁殖产更多的卵,孵出更多的雏鸟,第二:、三次则相反。②农药的使用对[树]麻雀繁殖成功有一定的影响。③麻雀可以作为环境污染的指示种:家麻雀体内非正常金属元素有铝、汞、镉和铅。当铅的积累超过2μg/g干重,病、死雏鸟的比例就会增加。④在发达国家,交通可以引起麻雀死亡。  相似文献   
26.
燕雀和麻雀代谢产热及消化道形态特征比较   总被引:5,自引:3,他引:2  
于 2 0 0 3年 4~ 5月在黑龙江省齐齐哈尔市地区以 1 0只燕雀 (Fringillamontifringilla)和 9只麻雀(Passermontanus)的耗氧量、肝脏和肌肉的线粒体呼吸、肝脏和肌肉的细胞色素C氧化酶活性及消化道形态特征等为指标 ,探讨了燕雀和麻雀代谢产热及消化道形态的差异。燕雀的代谢率、肝脏和肌肉的线粒体呼吸及细胞色素C氧化酶活性均显著低于麻雀 ;而消化道总长度及小肠长度均明显高于麻雀。表明选择压力的不同塑造了燕雀和麻雀对环境的适应对策不同  相似文献   
27.
本文重新描述峰革赛螨Gamasellus montanus(Willmann,1936)成螨。  相似文献   
28.
When introduced into new regions, invading organisms leave many native pathogens behind and also encounter evolutionarily novel disease threats. In the presence of predominantly novel pathogens that have not co-evolved to avoid inducing a strong host immune response, costly and potentially dangerous defenses such as the systemic inflammatory response could become more harmful than protective to the host. We therefore hypothesized that introduced populations exhibiting dampened inflammatory responses will tend to be more invasive. To provide initial data to assess this hypothesis, we measured metabolic, locomotor, and reproductive responses to inflammatory challenges in North American populations of the highly invasive house sparrow (Passer domesticus) and its less-invasive relative, the tree sparrow (Passer montanus). In the house sparrow, there was no effect of phytohemagglutinin (PHA) challenge on metabolic rate, and there were no detectable differences in locomotor activity between lipopolysaccharide (LPS)-injected birds and saline-injected controls. In contrast, tree sparrows injected with PHA had metabolic rates 20–25% lower than controls, and LPS injection resulted in a 35% drop in locomotor activity. In a common garden captive breeding experiment, there was no effect of killed-bacteria injections on reproduction in the house sparrow, while tree sparrows challenged with bacteria decreased egg production by 40% compared to saline-injected controls. These results provide some of the first data correlating variation in immune defenses with invasion success in introduced-vertebrate populations.  相似文献   
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30.
ABSTRACT Mountain Plovers (Charadrius montanus) are grassland birds that often breed in close association with colonies of black‐tailed prairie dogs (Cynomys ludovicianus). However, not all colonies provide plover nesting habitat or habitat of equal quality, and the characteristics of colonies important for plovers remain poorly understood. Over two years, I used plover distribution surveys, territory mapping, and habitat sampling to study habitat use by plovers in prairie dog colonies in shortgrass prairie in northeastern New Mexico. My objective was to document important components of plover breeding habitat in colonies by comparing characteristics of used and unused habitats at three spatial scales: colony, territory, and nest‐site. I found evidence of plover breeding in 14 of 44 colonies in 2009 and 13 of 43 colonies in 2010. Based on logistic regression, the probability of a colony being occupied by plovers was positively associated with colony size, but negatively associated with mean vegetation height. Preference for larger colonies could relate to minimum habitat requirements, or a potential tendency of this species to nest in social clusters. Shorter vegetation height was strongly correlated with greater bare ground and lower forb/subshrub cover, all characteristics that may be related to plover predator avoidance and foraging microhabitat. At both the territory and nest‐site scale, areas used by plovers had shorter vegetation, more bare ground, and less forb/subshrub cover than unused areas. Nest sites were also more sloped, perhaps to reduce risk of flooding, and located further away from the nearest prairie dog burrow, perhaps to reduce risk of disturbance. Overall, my results show that plover use of prairie dog colonies was influenced by landscape and habitat features of colonies, and suggest that large colonies are particularly valuable because they are most likely to contain adequate areas with preferred habitat characteristics.  相似文献   
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