行为的结构、刚性和多样性

有关动物行为的定义、结构和多样性是一个被长期忽视的研究领域。然而,动物行为多样性不仅是一个生物多样性基础理论问题,也与濒危动物的成功保护有关。本文定义了动物行为以及行为的刚性与弹性,探讨了行为表达的空间条件以及生境因素与行为多样性之间的关系。我们发现雌雄大熊猫个体在较大的活动空间里的发情行为表现的频次及活动频率显著地高于那些在较小的空间里的雌雄个体,说明活动空间对雄性或雌性大熊猫的发情行为有显著影响。圈养空间影响麋鹿的社会行为、通讯行为和聚群行为。圈养在小圈中的麋鹿没有出现同性聚群现象,当圈养麋鹿野放后即表现出这种现象。圈养环境中长大的动物个体由于缺乏行为的表达空间,仅仅表现出刚性大的行为,丧失了许多弹性大的行为,从而导致动物行为的多样性下降。对那些生活在开阔草原和荒漠上的野生有蹄类动物实施迁地保护时,必须考虑其逃逸空间,为那些动物建立自然保护区时,则必须考虑其迁移空间。此外,动物行为的多样性与生境元素有关。我们应当给圈养动物提供复杂而多样的环境,以增加圈养野生动物表达寻找食物、建立领域、筑巢和避开不利环境等行为的可能性,维持濒危个体的行为多样性。     

Passerines may be sufficiently plastic to track temperature‐mediated shifts in optimum lay date

Projecting the fates of populations under climate change is one of global change biology's foremost challenges. Here, we seek to identify the contributions that temperature‐mediated local adaptation and plasticity make to spatial variation in nesting phenology, a phenotypic trait showing strong responses to warming. We apply a mixed modeling framework to a Britain‐wide spatiotemporal dataset comprising >100 000 records of first egg dates from four single‐brooded passerine bird species. The average temperature during a specific time period (sliding window) strongly predicts spatiotemporal variation in lay date. All four species exhibit phenological plasticity, advancing lay date by 2–5 days °C^?1. The initiation of this sliding window is delayed further north, which may be a response to a photoperiod threshold. Using clinal trends in phenology and temperature, we are able to estimate the temperature sensitivity of selection on lay date (B), but our estimates are highly sensitive to the temporal position of the sliding window. If the sliding window is of fixed duration with a start date determined by photoperiod, we find B is tracked by phenotypic plasticity. If, instead, we allow the start and duration of the sliding window to change with latitude, we find plasticity does not track B, although in this case, at odds with theoretical expectations, our estimates of B differ across latitude vs. longitude. We argue that a model combining photoperiod and mean temperature is most consistent with current understanding of phenological cues in passerines, the results from which suggest that each species could respond to projected increases in spring temperatures through plasticity alone. However, our estimates of B require further validation.     

Environmental variability and population dynamics: do European and North American ducks play by the same rules?

Density dependence, population regulation, and variability in population size are fundamental population processes, the manifestation and interrelationships of which are affected by environmental variability. However, there are surprisingly few empirical studies that distinguish the effect of environmental variability from the effects of population processes. We took advantage of a unique system, in which populations of the same duck species or close ecological counterparts live in highly variable (north American prairies) and in stable (north European lakes) environments, to distinguish the relative contributions of environmental variability (measured as between‐year fluctuations in wetland numbers) and intraspecific interactions (density dependence) in driving population dynamics. We tested whether populations living in stable environments (in northern Europe) were more strongly governed by density dependence than populations living in variable environments (in North America). We also addressed whether relative population dynamical responses to environmental variability versus density corresponded to differences in life history strategies between dabbling (relatively “fast species” and governed by environmental variability) and diving (relatively “slow species” and governed by density) ducks. As expected, the variance component of population fluctuations caused by changes in breeding environments was greater in North America than in Europe. Contrary to expectations, however, populations in more stable environments were not less variable nor clearly more strongly density dependent than populations in highly variable environments. Also, contrary to expectations, populations of diving ducks were neither more stable nor stronger density dependent than populations of dabbling ducks, and the effect of environmental variability on population dynamics was greater in diving than in dabbling ducks. In general, irrespective of continent and species life history, environmental variability contributed more to variation in species abundances than did density. Our findings underscore the need for more studies on populations of the same species in different environments to verify the generality of current explanations about population dynamics and its association with species life history.     

幼年蝙蝠下丘神经元的听空间特性

实验分别在出生后４周龄的幼年和成年鲁氏菊头蝠（Ｒｈｉｎｏｌｏｐｈｕｓｒｏｕｘｉ）上进行。使用移动声刺激装置,高频喇叭可在动物头部前方水平方向１８０度、垂直方向６０度的范围内移动。玻璃微电极记录单个神经元的听反应。实验考察了幼年和成年动物下丘神经元的听空间特性,共观察了３０１个神经元,其中幼年动物１４８个,成年动物１５３个。结果表明,４周龄的幼年动物下丘听神经元已表现出方向敏感性,即每个听神经元均有一个特定的最佳反应中心和反应域。但神经元听反应中心在听空间的分布相当弥散,大多数位于对侧水平方向２０—８０度、垂直方向上下１５度范围内。而成年动物听神经元反应中心的分布则相当集中,局限地分布于对侧水平方向２８－５０度,垂直方向０—１０度范围内,两者构成明显差异。     

Bayesian analysis of wildlife age-at-harvest data

SUMMARY: State and federal natural resource management agencies often collect age-structured harvest data. These data represent finite realizations of stochastic demographic and sampling processes and have long been used by biologists to infer population trends. However, different sources of data have been combined in ad hoc ways and these methods usually failed to incorporate sampling error. In this article, we propose a "hidden process" (or state-space) model for estimating abundance, survival, recovery rate, and recruitment from age-at-harvest data that incorporate both demographic and sampling stochasticity. To this end, a likelihood for age-at-harvest data is developed by embedding a population dynamics model within a model for the sampling process. Under this framework, the identification of abundance parameters can be achieved by conducting a joint analysis with an auxiliary data set. We illustrate this approach by conducting a Bayesian analysis of age-at-harvest and mark-recovery data from black bears (Ursus americanus) in Pennsylvania. Using a set of reasonable prior distributions, we demonstrate a substantial increase in precision when posterior summaries of abundance are compared to a bias-corrected Lincoln-Petersen estimator. Because demographic processes link consecutive abundance estimates, we also obtain a more realistic biological picture of annual changes in abundance. Because age-at-harvest data are often readily obtained, we argue that this type of analysis provides a valuable strategy for wildlife population monitoring.     

Assessing the impact of deforestation and climate change on the range size and environmental niche of bird species in the Atlantic forests,Brazil

Aim Habitat loss and climate change are two major drivers of biological diversity. Here we quantify how deforestation has already changed, and how future climate scenarios may change, environmental conditions within the highly disturbed Atlantic forests of Brazil. We also examine how environmental conditions have been altered within the range of selected bird species. Location Atlantic forests of south‐eastern Brazil. Methods The historical distribution of 21 bird species was estimated using Maxent . After superimposing the present‐day forest cover, we examined the environmental niches hypothesized to be occupied by these birds pre‐ and post‐deforestation using environmental niche factor analysis (ENFA). ENFA was also used to compare conditions in the entire Atlantic forest ecosystem pre‐ and post‐deforestation. The relative influence of land use and climate change on environmental conditions was examined using analysis of similarity and principal components analysis. Results Deforestation in the region has resulted in a decrease in suitable habitat of between 78% and 93% for the Atlantic forest birds included here. Further, Atlantic forest birds today experience generally wetter and less seasonal forest environments than they did historically. Models of future environmental conditions within forest remnants suggest generally warmer conditions and lower annual variation in rainfall due to greater precipitation in the driest quarter of the year. We found that deforestation resulted in a greater divergence of environmental conditions within Atlantic forests than that predicted by climate change. Main conclusions The changes in environmental conditions that have occurred with large‐scale deforestation suggest that selective regimes may have shifted and, as a consequence, spatial patterns of intra‐specific variation in morphology, behaviour and genes have probably been altered. Although the observed shifts in available environmental conditions resulting from deforestation are greater than those predicted by climate change, the latter will result in novel environments that exceed temperatures in any present‐day climates and may lead to biotic attrition unless organisms can adapt to these warmer conditions. Conserving intra‐specific diversity over the long term will require considering both how changes in the recent past have influenced contemporary populations and the impact of future environmental change.     

济南市城市绿地可达性分析

以济南市1989、1996和2004年SPOT遥感卫星影像数据解译的城市绿地分类图、道路图和水系图为基础数据资料,在遥感(RS)和地理信息系统(GIS)技术支持下,运用景观可达性的概念与原理,采用费用加权距离方法,对济南市整体绿地系统和公园与广场绿地可达性的时空动态变化及其原因进行了分析。研究结果表明:1)济南市城市绿地的可达性不断提高与改善;2)济南市城市绿地可达性的空间格局变化明显,但仍不均衡、不太合理;3)城市绿地面积和斑块数量的不断增加、绿地分布格局的日益均衡和道路网的日臻完善是可达性不断提高的主要原因;4)城市绿地可达性分析是衡量城市绿地服务功能社会公平性的有力手段,充分体现城市建设“以人为本”的理念,是目前生态城市评价指标体系的必要补充。因此,城市绿地可达性分析结果可为合理调整与设计城市绿地系统提供科学依据。     

气生植物的生物学特性及研究展望

气生植物是指不需要土壤,生长所需的水分和营养可以全部来自空气的植物。它既不同于附生植物．也不同于具有气生根的植物。主要包括地衣、苔藓、蕨、凤梨科和兰科植物中的某些附生类群。它们没有根或者根不发达,仅起固定植株的作用。因为气生植物直接从空气中吸收水分和养分,但空气中的水分和养分毕竞是有限的,所以这些植物一般都具有很强的利用水分及养分的能力,很多植物已经成为有效地检测环境变化的“指示生物”和去除环境污染的修复植物。另外,因为这些植物具有忍受恶劣环境条件的生理基础,还可能成为适应空间环境的先锋植物,在空间植物学研究中将具有特殊的意义。     

前入路腹膜前修补腹股沟疝82 例临床分析

目的:探讨Modified Kugel补片治疗腹股沟疝的手术操作要点,并评价其疗效。方法:对2010年1~12月我院应用ModifiedKugel补片行开放性前入路腹膜前修补术的82例临床资料进行回顾性分析。结果:平均手术时间(55±10)min,术后住院(5.2±1.4)d。术后无尿潴留、切口感染等并发症。全组病人伤口一期愈合,无浆液肿及感染发生。术后随访12-23个月,无复发。结论:应用Modified Kugel补片修补腹股沟疝是一种创伤小、无张力、安全的手术方式,术后恢复快,近期疗效满意。     

Beyond barcoding: A mitochondrial genomics approach to molecular phylogenetics and diagnostics of blowflies (Diptera: Calliphoridae)

Members of the Calliphoridae (blowflies) are significant for medical and veterinary management, due to the ability of some species to consume living flesh as larvae, and for forensic investigations due to the ability of others to develop in corpses. Due to the difficulty of accurately identifying larval blowflies to species there is a need for DNA-based diagnostics for this family, however the widely used DNA-barcoding marker, cox1, has been shown to fail for several groups within this family. Additionally, many phylogenetic relationships within the Calliphoridae are still unresolved, particularly deeper level relationships. Sequencing whole mt genomes has been demonstrated both as an effective method for identifying the most informative diagnostic markers and for resolving phylogenetic relationships. Twenty-seven complete, or nearly so, mt genomes were sequenced representing 13 species, seven genera and four calliphorid subfamilies and a member of the related family Tachinidae. PCR and sequencing primers developed for sequencing one calliphorid species could be reused to sequence related species within the same superfamily with success rates ranging from 61% to 100%, demonstrating the speed and efficiency with which an mt genome dataset can be assembled. Comparison of molecular divergences for each of the 13 protein-coding genes and 2 ribosomal RNA genes, at a range of taxonomic scales identified novel targets for developing as diagnostic markers which were 117–200% more variable than the markers which have been used previously in calliphorids. Phylogenetic analysis of whole mt genome sequences resulted in much stronger support for family and subfamily-level relationships. The Calliphoridae are polyphyletic, with the Polleninae more closely related to the Tachinidae, and the Sarcophagidae are the sister group of the remaining calliphorids. Within the Calliphoridae, there was strong support for the monophyly of the Chrysomyinae and Luciliinae and for the sister-grouping of Luciliinae with Calliphorinae. Relationships within Chrysomya were not well resolved. Whole mt genome data, supported the previously demonstrated paraphyly of Lucilia cuprina with respect to L. sericata and allowed us to conclude that it is due to hybrid introgression prior to the last common ancestor of modern sericata populations, rather than due to recent hybridisation, nuclear pseudogenes or incomplete lineage sorting.