BIODIVERSITY AND CONSERVATION OF FRESHWATER FISH IN HONG KONG, CHINA

Hong Kong Special Administrative Region,China,has an area of1095km2and is located at the edge of thenorthern tropical zone.The landscape is dominated byhills and ravines withflat landrestrictedtothe lowflood-plains and coastal regions.Inthis hilly domain,the smallrocky streams are typically fast flowing at their uplandsources,and graduallyreduceinspeed asthey wind alonghill cuttings to reach the lowlands.While streams arecommonlyfound,rivers are very limited in number.Thefewlong and meanderi…     

Ecophysiological attributes of adult overwintering in insects: insights from a field study of the nut weevil,Curculio nucum

Abstract Diapausing insect species have evolved a great diversity of life cycles, although overwintering occurs at a single development stage within most species. Understanding why diapause has evolved towards a given life stage requires investigation of both the ecological and physiological attributes. Notably, it is suggested that adult overwintering is more energy‐demanding than larval overwintering but it brings fitness gains by allowing adults to be synchronized with their seasonal requisites through an early spring emergence. This hypothesis is tested in field conditions in the nut weevil Curculio nucum, whose life cycle comprises an obligate 2‐year, nonfeeding underground phase, including a larval, followed by an adult, overwintering. In this species, adult wintering leads to an early spring emergence; at first glance, however, this does not enhance synchronization between weevils and their host because adults emerge more than 1 month before starting to breed. It is suggested that adult overwintering ultimately evolved in response to the phenology of the host, by allowing females to oviposit in nuts before their full sclerotinization. Adult overwintering appears to be costly because adults postpone reproduction for 1 year, incur a significant weight loss and require feeding before egg laying. Surprisingly, lipids are unaffected during diapause, lipogenesis even being likely in the summer metamorphosis. These results suggest that the lipids involved in egg production may entirely come from the larval stages, whereas the other nutrients are acquired through adult feeding but this remains to be tested.     

A novel simple extracellular leucine-rich repeat (eLRR) domain protein from rice (OsLRR1) enters the endosomal pathway and interacts with the hypersensitive-induced reaction protein 1 (OsHIR1)

Receptor-like protein kinases (RLKs) containing an extracellular leucine-rich repeat (eLRR) domain, a transmembrane domain and a cytoplasmic kinase domain play important roles in plant disease resistance. Simple eLRR domain proteins structurally resembling the extracellular portion of the RLKs may also participate in signalling transduction and plant defence response. Yet the molecular mechanisms and subcellular localization in regulating plant disease resistance of these simple eLRR domain proteins are still largely unclear. We provided the first experimental evidence to demonstrate the subcellular localization and trafficking of a novel simple eLRR domain protein (OsLRR1) in the endosomal pathway, using both confocal and electron microscopy. Yeast two-hybrid and in vitro pull-down assays show that OsLRR1 interacts with the rice hypersensitive-induced response protein 1 (OsHIR1) which is localized on plasma membrane. The interaction between LRR1 and HIR1 homologs was shown to be highly conserved among different plant species, suggesting a close functional relationship between the two proteins. The function of OsLRR1 in plant defence response was examined by gain-of-function tests using transgenic Arabidopsis thaliana . The protective effects of OsLRR1 against bacterial pathogen infection were shown by the alleviating of disease symptoms, lowering of pathogen titres and higher expression of defence marker genes.     

Scent-Matching Dogs Determine Number of Unique Individuals From Scat

ABSTRACT Noninvasive scat sampling methods can generate large samples sizes, collected over vast landscapes, ideal for addressing wildlife conservation and management questions. However, the cost of genotyping scat samples limits the accessibility of these techniques. We describe detection-dog methods for matching large numbers of scat samples to the individual, reducing or eliminating the need for sample genotyping. Three dogs correctly matched 25 out of 28 samples from 6 captive maned wolves (Chrysocyon brachyurus) of known identity. Sample scent-matching can increase overall accessibility and breadth of applications of noninvasive scat-collection methods to important landscape scale problems in wildlife sciences.     

尼日利亚西南部森林区域中大猩猩的状况调查

我们利用标准化调查和广泛调查两种方法对尼日利亚西南部森林中黑猩猩(Pan troglodytes)的分布状态进行了调查。本研究确认该地区总计2 443·58 km2的15个森林保护区内存在该物种。然而基于间接证据,该地区之前仅有8个森林保护区共计1 920·48 km2被调查过。我们将独立收集的年度数据根据不同保护区进行分类总结并且估计了建巢黑猩猩的个体密度。研究结果显示该地区的黑猩猩呈低密度高分散分布,其中只有Eba和Ise两个森林保护区中黑猩猩的分布密度显著大于0·20/km2。研究区域内四个森林保护区中黑猩猩的建巢数大于10 (Akure/Ofosu森林保护区,13个; Oluwa森林保护区, 11个;Ise森林保护区22个; Ago-Owu森林保护区,11个)。此外,在Ise森林保护区内我们观察到黑猩猩其它活动(例如观望行为,发声行为,取食迹象和粪便)的频次显著高于其它森林保护区。研究结果表明,残余且易于管理的黑猩猩种群分布于该调查区域。建议采取适当的保护措施来保证它们的继续生存     

The regional variation of aboveground live biomass in old-growth Amazonian forests

The biomass of tropical forests plays an important role in the global carbon cycle, both as a dynamic reservoir of carbon, and as a source of carbon dioxide to the atmosphere in areas undergoing deforestation. However, the absolute magnitude and environmental determinants of tropical forest biomass are still poorly understood. Here, we present a new synthesis and interpolation of the basal area and aboveground live biomass of old‐growth lowland tropical forests across South America, based on data from 227 forest plots, many previously unpublished. Forest biomass was analyzed in terms of two uncorrelated factors: basal area and mean wood density. Basal area is strongly affected by local landscape factors, but is relatively invariant at regional scale in moist tropical forests, and declines significantly at the dry periphery of the forest zone. Mean wood density is inversely correlated with forest dynamics, being lower in the dynamic forests of western Amazonia and high in the slow‐growing forests of eastern Amazonia. The combination of these two factors results in biomass being highest in the moderately seasonal, slow growing forests of central Amazonia and the Guyanas (up to 350 Mg dry weight ha^?1) and declining to 200–250 Mg dry weight ha^?1 at the western, southern and eastern margins. Overall, we estimate the total aboveground live biomass of intact Amazonian rainforests (area 5.76 × 10⁶ km² in 2000) to be 93±23 Pg C, taking into account lianas and small trees. Including dead biomass and belowground biomass would increase this value by approximately 10% and 21%, respectively, but the spatial variation of these additional terms still needs to be quantified.     

Morphology and phylogenetic interpretation of a new Cambrian edrioasteroid (Echinodermata) from Spain

Abstract: The edrioasteroid, Aragocystites belli gen. nov. sp. nov. from the middle Cambrian Murero Formation of Spain, is described based on a small number of very well‐preserved specimens. Important anatomical characteristics include star‐shaped and pseudoclavate theca, rare or absent epispires, well‐developed interradially positioned oral plates and several unorganized cover plates associated with each widely exposed flooring plate. A phylogenetic analysis including several Cambro–Ordovician species shows it is more derived than Stromatocystites and Totiglobus but is a sister group to a clade comprising Cambraster and Edriodiscus. Ontogenetic observations based on juveniles of 5 mm in diameter suggest that this species changed thecal shape markedly during growth. A. belli gen. nov. sp. nov. probably lived in quiet environments where it attached directly to the sea floor on stabilized substrates.