Habitat use of urban Tree Sparrows in the process of urbanization: Beijing as a case study

The Tree Sparrow (Passer montanus) is a dominant species in urban bird communities. With the development of urbanization, the habitats and sources of food for Tree Sparrows are decreasing. Can the urban Tree Sparrow adapt to changes in the urban environment? To answer this question, we studied the habitat use of Tree Sparrows in eight types of urban areas in Beijing. The results show that the number of both breeding and wintering Tree Sparrows decreased with increasing urbanization. The habitat use of Tree Sparrows, analyzed using stepwise discriminant analysis, was positively correlated with the number of brick bungalows, coniferous and broad-leaved trees and air conditioners. It was negatively correlated with the area of high buildings and hardened roads, pedestrian and automobile flux. This indicates that the Tree Sparrow had not adapted to rapid urbanization even though it is a generally adaptable species. Urban planning should take birds such as the Tree Sparrow into consideration. __________ Translated from Biodiversity Science, 2006, 14(5): 372–381 [译自:生物多样性]     

风速和持续时间对树麻雀能量收支的影响

风是自然环境中常见的因子之一,会对动物的行为以及能量收支产生不同程度的影响。为探讨不同风速和持续时间对树麻雀能量收支的影响,以3种风速(0.2-0.4、1.2-1.4、3.2-3.6 m/s)和3种持续时间(1、2、4 h)的9组树麻雀进行为期1周的不同风环境驯化,测定其体重、体温和摄食量、摄水量、排泄粪量、排泄次数、摄入能、排泄粪能、排出水热能散失、消化能、同化能并计算消化率和同化率。去除初体重影响和双因素分析的结果发现,摄水量(排出水量)和排出水热能散失随着风速增大而显著减少(P < 0.001);持续时间与树麻雀的摄入能、粪能和散热调节的次数显著相关(P < 0.01),其能量收支最高和散热调节次数最多为2 h,最低(少)为4 h;双因素交互作用对树麻雀能量收支的影响不显著。3级风速(4 m/s)和持续时间4 h以内的风环境不会对树麻雀的能量收支产生显著影响。     

Genetic variation and relationships in Laetiporus sulphureus s. lat., as determined by ITS rDNA sequences and in vitro growth rate

The aim of this study was to characterise the genetic variation and molecular relationships of the brown rot polypore, Laetiporus sulphureus s. lat., from Europe, South America, Africa, and Asia, using ITS sequences of the nu-rDNA and by comparing the growth rate in vitro. In a NJ analysis of the sequences of 130 individuals of L. sulphureus s. lat., eight distinct clusters emerged, supported by BS values of 70-100 %. Within each cluster, the ITS rDNA sequence variation was below 3 %. The sequences were also analysed together with Laetiporus sequences available from GenBank. Results demonstrated the possible presence of L. huroniensis in Europe (invalidly named L. montanus) and L. gilbertsonii in South America, and provided more information on the Pan-American and European distribution of one of the clades, currently known in North America as L. sulphureus. L. conifericola formed a separate distinct clade. Moreover, the analysis revealed two unknown Laetiporus taxa in Korea, one in South Africa, and one in Europe. As L. sulphureus is described from Europe (France), and we show that more than one taxon exist here, it is presently not possible to define L. sulphureus s. str. Certain biological differences between some of the clades (in vitro growth rates, chemical composition, and pigmentation) were demonstrated and discussed.     

[树]麻雀羽再生的能量预算和水代谢散热调节

为探讨[树]麻雀的羽再生能力、能量预算对策和有效的散热调节方式,对3组(对照CF、去飞羽FF和去尾羽组TF)[树]麻雀(Passer montanus)进行4周驯养(Acclimation)。结果发现:[树]麻雀具有较强的羽再生能力和飞羽参与个体保温。羽再生[树]麻雀能量收支水平降低极显著(P﹤0.001),FF组和TF组比CF组减少依次为:摄入能19.77%和7.17%、消化能18.79%和6.47%、同化能18.73%和6.46%、粪能28.66%和13.35%、水代谢散热热能26.95%和7.43%、排泄次数33.71%和14.40%,增加依次为:消化率1.23%和0.78%、同化率1.35%和0.84%。个体能值水平,体重CF、TF和FF组(P﹤0.05)依次降低,体温组间变化不显著(P﹥0.05)。体内能量储备,血糖、肌糖原、体脂和水分含量组间差异不显著(P﹥0.05),肝糖原含量、体脂重组间差异显著(P﹤0.05)。器官水平包括心脏、肾脏、腺胃、小肠、盲肠和总消化道长度及质量出现积极的响应。日代谢水量组间差异极显著(P﹤0.001)。组间日排泄次数最少平均为56.11次和最多可达96.34次/只。结果表明:羽再生[树]麻雀分别选择了不同程度的降低能量收支水平,提高摄入食物的消化、吸收效率,动用体内能量储备来获取摄入能量不足部分,降低器官总能耗的能量预算对策和不同的新羽(再生羽枚数:飞羽部分和尾羽全部)再生的能量投资对策。泄殖腔排出(粪尿混合物)水是鸟类特有的、迅速的和有效的散热调节方式。     

Seasonal acclimatization of metabolism in Eurasian tree sparrows (Passer montanus)

Acclimatization to winter conditions is an essential prerequisite for survival of small passerines of the northern temperate zone. Changes in photoperiod, ambient temperature and food availability trigger seasonal acclimatization in physiology and behavior of many birds. In the present study, seasonal adjustments in several physiological, hormonal, and biochemical markers were examined in wild-captured Eurasian tree sparrows (Passer montanus) from the Heilongjiang Province in China. In winter sparrows had higher body mass and basal metabolic rate (BMR). Consistently, the dry mass of liver, heart, gizzard, small intestine, large intestine and total digestive tract were higher in winter than in that in summer. The contents of mitochondrial protein in liver, and state-4 respiration and cytochrome c oxidase (COX) activity in liver and muscle increased significantly in winter. Circulating level of serum triiodothyronine (T₃) was significantly higher in winter than in summer. Together, these data suggest that tree sparrows mainly coped with cold by enhancing thermogenic capacities through increased organ masses and heightened activity of respiratory enzymes activities. The results support the view that prominent winter increases in BMR are manifestations of winter acclimatization in tree sparrows and that seasonal variation in metabolism in sparrows is similar to that in other small temperate-wintering birds.     

树麻雀表型的环境适应进化

树麻雀(Passer montanus)分布范围广、海拔梯度大,也是人类活动的伴随物种。对中国837个样本的10个形态特征与温度、日照、海拔和风速等4个主要环境因子进行相关分析,结果显示:树麻雀的体重、嘴裂、翅长、尾长、跗跖长、脑骨宽、眼间距与日照因子显著相关(P0.05),体重、体长、翅长、尾长、跗跖长与海拔因子显著相关(P0.05),体重、嘴峰、翅长、脑骨长与温度因子显著相关(P0.05),表明树麻雀的形态指标易随环境因子的变化而变化。通过控制经度和海拔两个变量,对形态指标与纬度的偏相关分析表明,体重、翅长、脑骨长和脑骨宽与纬度呈显著正相关(P0.05),体表突出部分嘴峰、嘴裂与纬度呈显著负相关(P0.05),即随着纬度的升高,树麻雀身体逐渐变大,符合贝格曼规律;体表突出部分嘴峰和嘴裂随纬度升高变短,符合阿伦规律。飞行能力与海拔因子呈极显著正相关(n=92,r=0.217,P=0.038),表明树麻雀在高海拔地区具有更强的飞行能力,这也许是它成为广布种的重要原因。     

鹰鹃在橙翅噪鹛巢中寄生繁殖

2011年和2012年每年的5月到8月,在甘肃莲花山地区共发现了5例鹰鹃(Hierococcyx sparverioides)在橙翅噪鹛(Garrulax elliotii)巢中寄生繁殖的案例.鹰鹃卵为椭圆形,浅蓝色,卵壳上没有斑点.测量了其中2枚卵,卵重分别为6.9g和7.2g,长径×短径分别为29.76 mm×20.40 mm和28.40mm×21.68 mm.鹰鹃幼鸟在出壳后的第20天离巢.     

Impaired hatching success and male-biased embryo mortality in Tree Sparrows

During the past 30 years, many species of farmland birds have declined dramatically in numbers in Northern Europe, a trend coinciding with a tremendous intensification of agriculture, although the exact causes of these declines remain unclear. One of the worst affected species is the Tree Sparrow (Passer montanus). We studied two Swedish Tree Sparrow populations during the years 1996–2004 and found that in both populations, almost half of all laid eggs remained unhatched. This led us to investigate whether the eggs failed to hatch because of: (1) eggs not being fertilised or (2) embryo mortality. Our analyses showed that all of the eggs investigated contained sufficient number of sperm for fertilisation and that they also had other visible signs indicating that fertilisation had occurred. Hatching failure was instead shown to result from embryo mortality. Using molecular techniques, we were able to determine that embryo mortality is more likely to affect male embryos than females and that the fledgling sex ratio was consequently highly female biased. The cause of this sex-biased embryo mortality remains unknown, but various potential explanations are discussed.     

Diversimorbus metrosiderotis gen. et sp. nov. and three new species of Holocryphia (Cryphonectriaceae) associated with cankers on native Metrosideros angustifolia trees in South Africa

The Cryphonectriaceae includes important tree pathogens, especially on the Myrtales. During a routine disease survey in the Western Cape Province of South Africa, a fungus resembling the Eucalyptus pathogen Holocryphia eucalypti was observed on native Metrosideros angustifolia (Myrtales). The aims of this study were to identify the fungus and to expand surveys for fungi in the Cryphonectriaceae on M. angustifolia. Fungi were identified based on DNA sequence comparisons and morphological features, and their pathogenicity was tested on M. angustifolia under field conditions. Based on morphology and multigene phylogenetic analyses of DNA sequence data from six gene regions, we describe a new genus including a single species and three new species of Holocryphia (Cryphonectriaceae) from M. angustifolia. These fungi are provided with the names Diversimorbus metrosiderotis gen. et sp. nov., Holocryphia capensis sp. nov., Holocryphia gleniana sp. nov., and Holocryphia mzansi sp. nov. We also revise H. eucalypti, the type of the genus, to include only isolates from Eucalyptus in South Africa. Research results indicated that H. mzansi may undergo host shifts between different tree genera in the Myrtaceae. Inoculation tests showed that isolates of all the newly described species can cause lesions on the branches of M. angustifolia, indicating that they are all pathogens of this tree.     

Experimental evidence for state-dependent nest weight in the blue tit, Cyanistes caeruleus

Parental investment in reproduction is generally limited by food availability, and so avian life-history research has traditionally focused on the brood rearing phase, when food requirements are greatest. Only relatively recently has the focus extended to the incubation phase, and even more recently to the nest-building phase, where observational and comparative evidence suggest that avian nest building is an energetically expensive and time-consuming activity. We aimed to experimentally test the limitations on this cost in a hole-breeding passerine, the blue tit (Cyanistes caeruleus), by providing supplementary food to experimental pairs during the nest-building period. In comparison with control females, that did not receive supplementary food, experimental females constructed heavier nests, with greater amounts of moss base but similar amounts of cup lining, despite there being no differences in the time taken to build the nest. This study provides empirical support for the hypothesis that avian nest building is a costly behaviour, limited by food availability.     

Effects of partial dehydration of recalcitrant Haemanthus montanus zygotic embryos on vigour of recovered seedlings

Cryopreservation is the most promising route for the long-term conservation of recalcitrant seed germplasm. Partial dehydration is a standard pre-treatment for the cryopreservation of zygotic embryos or embryonic axes excised from recalcitrant seeds since it reduces the likelihood of lethal ice-crystal generation during cooling. However, there is presently little to no understanding of how pre-conditioning treatments such as partial dehydration imposed at the embryonic stage are translated or manifested during subsequent in and ex vitro seedling growth. The present study assessed the vigour of seedlings recovered from partially dried (D) zygotic embryos, excised from recalcitrant Haemanthus montanus (Baker) seeds. Seedlings recovered from fresh (F) and partially dried (D) embryos in vitro, were hardened-off ex vitro, and subsequently subjected to either 42 days of watering (W) or 42 days of water deficit (S). The adverse effects of partial dehydration on seedling dry mass accumulation observed after 60 days in vitro growth did not disappear with an extension of the in vitro growth period but did appear to be reversible during ex vitro growth. A water stress during ex vitro growth dominated over the effects of embryo pre-treatment with relative growth rates in FS-seedlings (recovered from fresh embryos and subsequently stressed) and DS-seedlings (recovered from dried embryos and subsequently stressed) being statistically comparable. D- and F-seedlings responded typically to the water stress but DS-, compared with FS-seedlings, appeared to have incurred permanent damage to their photosynthetic machinery, were exposed to lower predawn water potentials, were less efficient at adjusting leaf water potential to meet transpirational demands, did not exhibit signs of osmotic adjustment, failed to adopt growth patterns that reduce transpirational water loss, and were more susceptible to persistent turgor loss. It was therefore not surprising that ex vitro seedling mortality occurred in more DS- than FS-seedlings. These results suggest that partial dehydration of recalcitrant H. montanus zygotic embryos, even when not followed by cooling, can reduce the vigour and drought tolerance of recovered seedlings.     

First report of Pandora neoaphidis resting spore formation in vivo in aphid hosts

The entomopathogenic fungus Pandora neoaphidis is a recognized pathogen of aphids, causes natural epizootics in aphid populations, and interacts and competes with aphid predators and parasitoids. Survival of entomophthoralean fungi in periods of unsuitable weather conditions or lack of appropriate host insects is accomplished mainly by thick-walled resting spores (zygospores or azygospores). However, resting spores are not known for some entomophthoralean species such as P. neoaphidis. Several hypotheses of P. neoaphidis winter survival can be found in the literature but so far these hypotheses do not include the presence of resting spores. Resting spores were found in an aphid population where P. neoaphidis was the only entomophthoralean fungus observed during surveys conducted in organic horticultural crops in greenhouses and open fields in Buenos Aires province, Argentina. This study sought to use molecular methods to confirm that these resting spores were, in fact, those of P. neoaphidis while further documenting and characterizing these resting spores that were produced in vivo in aphid hosts. The double-walled resting spores were characterized using light and transmission electron microscopy. The Argentinean resting spores clustered together with P. neoaphidis isolates with bootstrap values above 98 % in the small subunit ribosomal RNA (SSU rRNA) sequence analysis and with bootstrap values above 99 % the Internal Transcribed Spacer (ITS) II region sequence analysis. This study is the first gene-based confirmation from either infected hosts or cultures that P. neoaphidis is able to produce resting spores.     

Identification key for European strand-forming house-rot fungi

An identification key for 20 common strand-forming indoor wood decay fungi is given. The key is based on observations of material from affected buildings and on wood samples that have been incubated in the laboratory. The key is with macro- and microscopic photographs.     

Semicircular canal system in early primates

Mammals with more rapid and agile locomotion have larger semicircular canals relative to body mass than species that move more slowly. Measurements of semicircular canals in extant mammals with known locomotor behaviours can provide a basis for testing hypotheses about locomotion in fossil primates that is independent of postcranial remains, and a means of reconstructing locomotor behaviour in species known only from cranial material. Semicircular canal radii were measured using ultra high resolution X-ray CT data for 9 stem primates (“plesiadapiforms”; n = 11), 7 adapoids (n = 12), 4 omomyoids (n = 5), and the possible omomyoid Rooneyia viejaensis (n = 1). These were compared with a modern sample (210 species including 91 primates) with known locomotor behaviours. The predicted locomotor agilities for extinct primates generally follow expectations based on known postcrania for those taxa. “Plesiadapiforms” and adapids have relatively small semicircular canals, suggesting they practiced less agile locomotion than other fossil primates in the sample, which is consistent with reconstructions of them as less specialized for leaping. The derived notharctid adapoids (excluding Cantius) and all omomyoids sampled have relatively larger semicircular canals, suggesting that they were more agile, with Microchoerus in particular being reconstructed as having had very jerky locomotion with relatively high magnitude accelerations of the head. Rooneyia viejaensis is reconstructed as having been similarly agile to omomyids and derived notharctid adapoids, which suggests that when postcranial material is found for this species it will exhibit features for some leaping behaviour, or for a locomotor mode requiring a similar degree of agility.     

Evolutionarily conserved thermal biology across continents: The North American lizard Plestiodon gilberti (Scincidae) compared to Asian Plestiodon

1.

The lizard genus Plestiodon (Scincidae; formerly Eumeces) is widespread in North America and Asia, but the thermal biology of only a few species has been studied.