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1.
ABSTRACT

Seasonal changes of parameters of full song were studied in a free-living population of chaffinches Fringilla coelebs during one entire reproductive period. Approximately 7000 strophes sung by 14 male chaffinches were recorded and analysed by sonography and a particular oscillographic method. While the general pattern of song strophes, i.e. characteristics of elements, number and arrangement of phrases, and final flourish, remained constant throughout the reproductive period, full song varied with respect to the repetition rate of strophes, number of strophe types used, intensity of singing, duration of strophes, and percentage of incomplete strophes sung. These changes are discussed as results of learning processes, social interactions in the population, and endogenous mechanisms activating memorized information.  相似文献   
2.
Borrelia burgdorferi sensu lato (s.l.) is the causative agent of Lyme borreliosis, the most common tick‐borne zoonosis of humans in Europe and North America. Here, we assessed the relative importance of different passerine bird species as tick hosts and their contribution to the B. burgdorferi s.l. transmission cycle in a rural residential area in Scotland. We caught 1229 birds of 22 species during the tick‐questing season. On average, 29% carried larval ticks (0.8 larvae per individual) and 5% carried nymph ticks (0.06 nymphs per individual). All attached ticks tested were Ixodes ricinus. Using a nested‐PCR, we found that 20% of nymphs tested positive to B. burgdorferi s.l. and all these were of the genospecies Borrelia garinii. We identified two new bird species carrying infected nymphs: Eurasian Siskin Carduelis spinus and European Greenfinch Carduelis chloris. Ground‐foraging species were more important than arboreal species in hosting I. ricinus nymphs and B. burgdorferi s.l. Common Blackbirds Turdus merula were the most common hosts, with Song Thrushes Turdus philomelos, Dunnocks Prunella modularis, European Greenfinches and Chaffinches Fringilla coelebs also hosting high rates of infection.  相似文献   
3.
Capsule Woodland birds were significantly less likely to occur in gardens in years of high beechmast crop.

Aim To test the hypothesis that woodland species that feed on beechmast will have significantly lower occurrence rates at garden feeders in mast years.

Methods Weekly winter occurrence rates at garden feeders between 1970/71 and 1999/2000 for 40 species were analysed in relation to annual beechmast abundance, classified into low, medium and high years. A repeated-measures logistic regression model was used to assess whether beechmast abundance explained further significant variation additional to underlying seasonal and annual trends.

Results Seven species that commonly feed on beechmast showed significantly lower occurrence in gardens in years of highest beechmast abundance: Great Spotted Woodpecker Dendrocopos major, Woodpigeon Columba palumbus, Great Tit Parus major, Coal Tit Periparus ater, Nuthatch Sitta europaea, Jay Garrulus glandarius and Chaffinch Fringilla coelebs. Blackbird Turdus merula and Siskin Carduelis spinus, which showed similar significant patterns, are likely to take beechmast as elements of their diet. Pied Wagtail Motacilla alba was the only insectivorous species to show significant effects, but occurrence was lowest in years of intermediate beechmast abundance. For the latter species, this may have been due to confounding effects of temperature, but there were no such confounding effects of either temperature, or the number of bird feeders provided in gardens, for the other nine species.

Conclusion Use of artificial food sources by birds in gardens is influenced by resources in the surrounding countryside, suggesting that food provided in gardens may play a significant part in the population dynamics of these species, that population monitoring without consideration of the garden habitat may be deficient, and that volunteer-based garden bird recording may provide data that can be used as an indicator of changes in the wider countryside.  相似文献   
4.
记述采自云南大理苍山的螳螂1新种,即云南华小翅螳Sinomiopteryx yunnanensis sp.nov.,模式标本保存于大理学院生命科学与化学学院。  相似文献   
5.
中越边境地区是全球生物多样性的热点地区,近年来不断有新种、分布新记录种报道。2017年,学者首次报道了德氏瘰螈(Paramesotriton deloustali Bourret,1934)在中国的分布,但仅描述了其线粒体全序列,缺乏其他生物学信息。本研究于2013年在云南省红河州哈尼族彝族自治州河口县境内大围山保护区(22°37′N,103°52′E,海拔350 m)采集到6号标本应为德氏瘰螈,包括雄性成体标本4号和雌性成体标本2号,对其形态和生境特征进行了详细描述。此次采集标本与模式标本系列形态吻合。基于细胞色素c氧化酶亚基I(COI)基因的系统发育分析结果显示,河口大围山德氏瘰螈种群与模式产地(越南北部永福省三岛"Tam Dao,Vinh Phuc Province"风景区)种群间的遗传分化较小(p-distance为0.6%),与2017年所报道的云南标本聚为一支(p-distance为0.5%)。德氏瘰螈目前仅记录于中越边境地区,分布地极为狭窄,种群数量未知。为了更好地了解和保护包括该物种在内的中越边境生物多样性,建议两国学者进行更多的合作研究。  相似文献   
6.
三江并流区域野生青刺果植物资源及合理开发浅析   总被引:2,自引:0,他引:2  
对青刺果的植物学特性及分布范围、理化指标和营养价值进行详细的分析,从多个角度探讨了它的的开发、利用价值,并结合三江并流区域内野生青刺果植物资源的分布、利用情况,提出了开发与保护的可持续发展问题。  相似文献   
7.
晚三叠世泡孔类苔藓动物Casianopora及其种系发生关系   总被引:1,自引:1,他引:0  
本文描述了窄唇纲苔藓动物的一个新种Casianoporaheisp.nov.,此新种发现于我国滇西北宁蒗彝族自治县松桂组15层(菊石Malayites-Pseudocardioceras带),是迄今已知的全球三叠纪泡孔类的一个最新代表。重新确定了Casianopora属(卡尼中期-诺利早期)的分类位置,它和Cystitrypa属(卡尼早期)都归入Fistuliporidae科。这两个三叠纪的属,与古生代和古生代后的一些泡孔类的种系发生关系的初步探讨表明,所有古生代后的窄唇纲的各个目(除环口目外),可能都是从同一演化根系上发展而来的。  相似文献   
8.
Capsule Declining farmland species were more abundant in these crops which can be matched to the birds' requirements.

Aims To assess the use of seed-bearing crop by a range of bird species in winter.

Methods The study was carried out over three winters at a site in County Durham (England). Eleven bird species were represented, five of which are nationally targeted for conservation action.

Results Bird abundance was significantly higher where wild bird cover crops were present. Kale Brassica napus and Quinoa Chenopodium quinoa were the most used crop species, although cereals and linseed were also used.

Conclusion Simple crop mixtures can be designed to meet the needs of farmland bird communities. Our results suggest that seed production may be limited within government agri-environment schemes by restrictions on fertilizer use. The agronomy of seed-bearing crops for birds requires further investigation.  相似文献   
9.
Seed dispersal is a central process in plant ecology with consequences for species composition and habitat structure. Some bird species are known to disperse the seeds they ingest, whereas others, termed ‘seed predators’, digest them and apparently play no part in dispersal, but it is not clear if these are discrete strategies or simply the ends of a continuum. We assessed dispersal effectiveness by combining analysis of faecal samples and bird density. The droppings of seed dispersers contained more entire seeds than those of typical seed predators, but over a quarter of the droppings of seed predators contained whole seeds. This effect was further magnified when bird density was taken into account, and was driven largely by one frequent interaction: the Chaffinch Fringilla coelebs, a typical seed predator and the most abundant bird species in the area and dispersed seeds of Leycesteria formosa, a non‐native plant with berry‐like fruits. These results suggest the existence of a continuum between seed predators and seed dispersers.  相似文献   
10.
We analyzed sequences from a 275-bp hypervariable region in the 5' end of the mitochondrial DNA control region in 190 common chaffinches (Fringilla coelebs) from 19 populations in Europe and North Africa, including new samples from Greece and Morocco. Coalescent techniques were applied to estimate the time to the most recent common ancestor (TMRCA) and divergence times of these populations. The first objective of this study was to infer the locations of refugia where chaffinches survived the last glacial episode, and this was achieved by estimating the TMRCA of populations in regions surrounding the Mediterranean that were unglaciated in the late Pleistocene. Although extant populations in Iberia, Corsica, Greece, and North Africa harbor haplotypes that are basal in a phylogenetic tree, this information alone cannot be used to infer that these localities served as refugia, because it is impossible to infer the ages of populations and their divergence times without also considering the population genetic processes of mutation, migration, and drift. Provided we assume the TMRCAs of populations are a reasonable estimate of a population's age, coalescent-based methods place resident populations in Iberia, Corsica, Greece, and North Africa during the time of the last glacial maximum, suggesting these regions served as refugia for the common chaffinch. The second objective was to determine when populations began diverging from each other and to use this as a baseline to estimate current levels of gene flow. Divergence time estimates suggest that European populations began diverging about 60,000 years before present. The relatively recent divergence of populations in North Africa, Italy, and Iberia may explain why classic migration estimates based on equilibrium assumptions are high for these populations. We compare these estimates with nonequilibrium-based estimates and show that the nonequilibrium estimates are consistently lower than the equilibrium estimates.  相似文献   
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