The circadian clock contributes to diurnal patterns of plant indirect defense in nature

The plant circadian clock regulates the rhythms of plant metabolism.Many herbivore-induced plant volatiles(HIPVs)fluctuate,diurnally,but the role of the circadian clock in the emission of HIPVs and their ecological consequences remains largely unknown.Here,we show that the timing of herbivore attack can alter the outcome of tri-trophic interactions,and this is mediated by the circadian clock,under both field and glasshouse conditions.Although most HIPV emissions did not have a circadian rhythm,the circadian clock modulated HIPV emissions in a time-dependent manner.HIPVs mediate tri-trophic interactions,and the circadian clock may affect these interactions by modulating HIPV emission in nature.

Delayed sexual maturity in males of Vespa velutina

Vespa velutina var nigrithorax （Lepelletier, 1835） is an invasive predator of bees accidentally introduced in France in 2004, and it is having a serious impact on apiculture and ecosystems. Studying the reproduction of an invasive species is key to assess its population dynamic. This study explores the sexual maturation of IT. velutina males and the evolution of their fertility. The main studied parameters were physiologic （spermiogenesis, spermatogenesis） and anatomic （testes size and structure, head width）. Two populations of males were described based on their emergence period： early males in early summer or classic males in autumn. Each testis has an average of 108 testicular follicles. Spermatogenesis is synchronous, with only 1 sperm production wave, and completed, on average, at 10.3 d after emergence with the degeneration of the testes. The sperm counts in seminal vesicles of mature males are 3 x 106 in October/November and 0.8 ~ 106 in June. In com- parison, females store 0.1 x 106 sperm in their spermathecae. The early males emerged from colonies made by fertilized queens. The reproductive potential of these early males seemed limited, and their fimction in the colony is discussed. The sperm stock evolution in autumn males suggests the occurrence of a reproductive pattern of male competition for the access to females and a single copulation per male. The synchronicity of male and foundress emergences and sexual maturation is of primary importance for the mating success and the future colony development.

Development of a multiprimer metabarcoding approach to understanding trophic interactions in agroecosystems

To understand trophic interactions and the precise ecological role of each predatory species,it is important to know which arthropod and plant resources are used by generalist predators in agroecosystems.Molecular approaches,such as the use of high-throughput sequencing(HTS),play a key role in identifying these resources.This study develops a multiprimer metabarcoding approach for screening the most common trophic interactions of two predatory arthropods with contrasting morphologies,Rhagonycha fulva(Coleoptera:Cantharidae)and Anthocoris nemoralis(Hemiptera:Anthocoridae)collected from a peach crop.To reduce the time and cost of this metabarcoding approach,we first evaluated the effect of using two different predator-pools of different size(10 and 23 individuals of the same species).We also used our system to analyze the performance of one and two primer pairs in the same library.Our results show that the analysis of 23 individuals together with the use of two primer pairs in the same library optimize the HTS analysis.Using these best-performing conditions,we then analyzed the entire bodies of field-collected predators as well as the washing solutions used to clean the insect bodies.We were able to identify both gut content(i.e.,diet)and external pollen load(i.e.,on the insects’bodies).This study also demonstrates the importance of washing predatory insects’bodies prior to HTS analysis when the target species have a considerable size(>10 mm)and hairy structures.This metabarcoding approach has significant potential for the study of trophic links in agriculture,revealing expected and unexpected trophic relationships.

社会解组理论与自杀

社会学家早期对凶杀和自杀的考察认为这两种形式的偏离行为是相似的。然而,近些年来凶杀与自杀之间的确切联系并没有得到探讨。不过,分别考察凶杀与自杀的研究通常显示同样的结构性因素预示着两种形式的偏离现象的增多。与此同时,有关凶杀和自杀的研究显示出某种反相关关系。本文利用美国疾病控制和预防中心和美国人口普查局的数据,同时使用社会解组理论作为指南,探讨了预测凶杀的因子是否可以适用于研究自杀。多因素回归分析显示,社会解组理论所总结的一些因素同样可以用于预测自杀率的升高。本文证明,有关犯罪的理论也许适用于研究自杀,从而使人们对偏离行为有更充分的了解。

Assurance of the existence of a trans-boundary population of the snow leopard(Panthera uncia)at Tsagaanshuvuut-Tsagan-Shibetu SPA at the Mongolia-Russia border

The existence of a trans-boundary population of the snow leopard(Panthera uncia)that inhabits the massifs of Tsagaanshuvuut(Mongolia)-Tsagan-Shibetu(Russia)was determined through non-invasive genetic analysis of scat samples and by studying the structure of territory use by a collared female individual.The genetic analysis included species identification of samples through sequencing of a fragment of the cytochrome b gene and individual identification using a panel of 8 microsatellites.The home range of a female snow leopard marked with a satellite Global Positioning System(GPS)collar was represented by the minimum convex polygon method(MCP)100,the MCP 95 method and the fixed kernel 95 method.The results revealed insignificant genetic differentiation between snow leopards that inhabit both massifs(minimal fixation index[FST]),and the data testify to the unity of the cross-border group.Moreover,5 common individuals were identified from Mongolian and Russian territories.This finding clearly shows that their home range includes territories of both countries.In addition,regular movement of a collared snow leopard in Mongolia and Russia confirmed the existence of a cross-border snow leopard group.These data support that trans-boundary conservation is important for snow leopards in both countries.We conclude that it is crucial for Russia to study the northern range of snow leopards in Asia.