Isolation ofRoumegueriella rufula as a new record from East Asia

Roumegueriella rufula (Ascomycota; Hypocreales) isolated from a soil sample collected in Taiwan is described as a new record from East Asia. Some observations are recorded, particularly on cultural characteristics of aGliocladium anamorph of this fungus, which has scarcely been reported since Bainier described both ascosporic and conidial forms as species ofGliocladium.     

Population prehistory of East Asia and the pacific as viewed from craniofacial morphology: The basic populations in East Asia,VII

Distance analyses were applied to 11 craniofacial measurements recorded in samples from East and Southeast Asia, Australia, Melanesia, Polynesia, and Micronesia for the purpose of assessing the biological affinities and possible origins of these populations. A clear separation between Australomelanesians and other populations from East and Southeast Asia and the Pacific is evident. The craniofacial variations suggest that the generalized Asian populations (Negritos, Dayaks, Lesser Sunda Islands, etc.) represent at least part of the morphological background of not only the majority of present Southeast Asians, but also the Neolithic Jomon people and their lineage in Japan, Polynesians, and western Micronesians. The original craniofacial features of Southeast Asians may have occurred as the result of convergent microevolution due to similar environmental conditions such as tropical rain forest. This supports the local-evolution hypothesis for modern Southeast Asian craniofacial features. © 1993 Wiley-Liss, Inc.     

Xylodon subflaviporus sp. nov. (Hymenochaetales,Basidiomycota) from East Asia

Xylodon subflaviporus (Hymenochaetales, Basidiomycota) is described as a new species collected from tropical and subtropical regions of East Asia. This new species is characterized by resupinate basidiocarps, a poroid hymenophore, pseudodimitic hyphal system, nodose-septate hyphae, four types of cystidia (capitate, acicular to cylindrical, subulate to ventricose, and apically-encrusted), and thin-walled, colorless, smooth and ellipsoid basidiospores. Bayesian, Maximum Likelihood and Maximum Parsimony algorithms were used to construct phylogenies inferred from the internal transcribed spacer (ITS) region of rDNA. Morphological and molecular studies, along with intercompatibility tests, confirmed the independent status of this species. Also, based on morphological and molecular evidence, six new combinations of Xylodon are proposed to accommodate species originally classified under Hyphodontia s.l., i.e. X. bubalinus, X. chinensis, X. mollissimus, X. nongravis, X. reticulatus and X. subtropicus. A key to known species of Hyphodontia s.l. with poroid, irpicoid or raduloid hymenophores is provided for the convenience in identification.     

Origin of modern humans in East Asia: clues from the Y chromosome

East Asia is one of the most important regions for studying modern human origin and evolution. A lot of efforts have been made to detect the genetic diversity and to reconstruct the evolutionary history of East Asians, especially using Y chromosome genetic data, in recent years. The Y chromosome data supports the African origin of modern humans in East Asia and the later migration to East Asia through the southern tropic coastline route, and then the northward migration occurred, leading to peopling of the main continent. The genetic data of the Y chromosome reflects a clear prehistoric evolution and migration course of East Asians. As well, the Y chromosome data of East Asians provides clues to elucidate modern human origins and evolution in the neighboring regions, i.e. America, Oceania and the Pacific Islands.     

Origin of modern humans in East Asia: clues from the Y chromosome

East Asia is one of the most important regions for studying modern human origin and evolution. A lot of efforts have been made to detect the genetic diversity and to reconstruct the evolutionary history of East Asians, especially using Y chromosome genetic data, in recent years. The Y chromosome data supports the African origin of modern humans in East Asia and the later migration to East Asia through the southern tropic coastline route, and then the northward migration occurred, leading to peopling of the main continent. The genetic data of the Y chromosome reflects a clear prehistoric evolution and migration course of East Asians. As well, the Y chromosome data of East Asians provides clues to elucidate modern human origins and evolution in the neighboring regions, i.e. America, Oceania and the Pacific Islands.     

Genetic variation of two apterous wasps Haplogonatopus apicalis and H. oratorius (Hymenoptera: Dryinidae) in East Asia

The females of Haplogonatopus (Hymenoptera: Dryinidae) are wingless. Thus, the migration ability of adult wasps should be highly restricted. However, passive dispersal of larvae parasitizing their hosts may be possible. In this study we discuss the genetic variation of H. apicalis Perkins and H. oratorius (Westwood) in East Asia, from the perspective of the geographical distribution and the long-distance migration ability of their hosts, using 807 bp of mitochondrial COI gene sequences. Genetic variation of H. apicalis parasitizing Sogatella furcifera (Horváth) was examined on the basis of individuals from western Japan, southern China, and northern Vietnam. High genetic diversity was observed but geographical populations were not recognized. For H. oratorius parasitizing Laodelphax striatellus (Fallén), individuals from the northern and southern coasts of eastern Japan, western Japan, eastern China, and Taiwan were examined. The southern coast of eastern Japan population was discriminated from the other populations, and three core haplotype groups moderately associated with geographical distribution were apparent. However, the population sampled at Hokuriku, located on the northern coast of eastern Japan, was composed of a mixture of haplotypes dominant in other locations, even geographically far separated from China. This may imply the occurrence of the migration pathway of L. striatellus from continental China toward eastern Japan. The results for two parasitoid species can be explained on the basis of the migration ability of the host species.     

Marine incursion into East Asia: a forgotten driving force of biodiversity

Episodic marine incursion has been a major driving force in the formation of present-day diversity. Marine incursion is considered to be one of the most productive ‘species pumps’ particularly because of its division and coalescence effects. Marine incursion events and their impacts on diversity are well documented from South America, North America and Africa; however, their history and impacts in continental East Asia largely remain unknown. Here, we propose a marine incursion scenario occurring in East Asia during the Miocene epoch, 10–17 Ma. Our molecular phylogenetic analysis of Platorchestia talitrids revealed that continental terrestrial populations (Platorchestia japonica) form a monophyletic group that is the sister group to the Northwest Pacific coastal species Platorchestia pacifica. The divergence time between the two species coincides with Middle Miocene high global sea levels. We suggest that the inland form arose as a consequence of a marine incursion event. This is the first solid case documenting the impact of marine incursion on extant biodiversity in continental East Asia. We believe that such incursion event has had major impacts on other organisms and has played an important role in the formation of biodiversity patterns in the region.     

Determinants of Influenza Transmission in South East Asia: Insights from a Household Cohort Study in Vietnam

To guide control policies, it is important that the determinants of influenza transmission are fully characterized. Such assessment is complex because the risk of influenza infection is multifaceted and depends both on immunity acquired naturally or via vaccination and on the individual level of exposure to influenza in the community or in the household. Here, we analyse a large household cohort study conducted in 2007–2010 in Vietnam using innovative statistical methods to ascertain in an integrative framework the relative contribution of variables that influence the transmission of seasonal (H1N1, H3N2, B) and pandemic H1N1pdm09 influenza. Influenza infection was diagnosed by haemagglutination-inhibition (HI) antibody assay of paired serum samples. We used a Bayesian data augmentation Markov chain Monte Carlo strategy based on digraphs to reconstruct unobserved chains of transmission in households and estimate transmission parameters. The probability of transmission from an infected individual to another household member was 8% (95% CI, 6%, 10%) on average, and varied with pre-season titers, age and household size. Within households of size 3, the probability of transmission from an infected member to a child with low pre-season HI antibody titers was 27% (95% CI 21%–35%). High pre-season HI titers were protective against infection, with a reduction in the hazard of infection of 59% (95% CI, 44%–71%) and 87% (95% CI, 70%–96%) for intermediate (1∶20–1∶40) and high (≥1∶80) HI titers, respectively. Even after correcting for pre-season HI titers, adults had half the infection risk of children. Twenty six percent (95% CI: 21%, 30%) of infections may be attributed to household transmission. Our results highlight the importance of integrated analysis by influenza sub-type, age and pre-season HI titers in order to infer influenza transmission risks in and outside of the household.     

基于ITS序列的东亚当归属植物的分类学研究

采用PCR直接测序法,测定了东亚地区狭义当归属Angelica s.s.及其近缘共7属40种代表植物的核糖体DNA ITS序列,并结合GenBank中相关植物的ITS序列(含外类群3种),应用遗传距离与系统树分析法对东亚地区狭义当归属植物内部以及当归属与其近缘属植物之间的亲缘关系进行了分析。结果表明:(1)广义当归属中的狭义当归属、柳叶芹属Czernaevia和高山芹属Coelopleurum之间的亲缘关系较近,山芹属Ostericum与它们的亲缘关系较远,这与果实形态、化学分析的结果一致,建议将山芹属作为一个相对独立的分类群处理。(2)ITS序列分析结果支持狭义当归属不是单起源的自然分类群,而应该被分成若干组的观点。(3)ITS序列以及化学成分分析结果表明,前胡属Peucedanum与狭义当归属之间的亲缘关系很近。(4)形态、化学成分以及ITS等多方面分析结果显示,当归A.sinensis与狭义当归属的多数植物之间均有一定的差距,其归属问题值得商榷。(5)ITS序列与化学成分的分析结果均显示藁本属Ligusticum不是一个自然类群。     

Phylogenetic Relationships of Sheep Populations from Coastal Areas in East Asia

Using the method of random sampling in typical colonies of the central area of the habitat and several electrophoresis techniques, the variations of 12 structural loci encoding blood protein of 60 Small-tailed Han sheep were examined and compared with those of four other sheep populations from coastal areas in East Asia to explore their phylogenetic relationships. Average heterozygosity of the five populations was: Kharkhorin sheep 0.3447, Ulaanbaatar sheep 0.3285, Small-tailed Han sheep 0.3157, Hu sheep 0.3884, and Cham Tribe sheep 0.2300. The earlier researchers' conclusion through documentary research, indicating that Small-tailed Han sheep and Hu sheep both evolved from Mongolian sheep, was further verified by the results of this study. Hu sheep, Small-tailed Han sheep, and Cham Tribe sheep were decreasingly affected by the bloodline of Mongolian sheep. A partial founder population, i.e., Mongolian sheep forming current Small-tailed Han sheep, possibly made a contribution to the bloodline of Cham Tribe sheep.