Palatability of tissues in Holothuria leucospilota (Brandt) from central west coast of India

The palatability of various organs (body wall, cuvierian gland, viscera, longitudinal muscle bands and gonads) of sea cucumber Holothuria leucospilota (Brandt) was studied by feeding experiments, performed on a freshwater fish Sarotherodon mossambicus and a marine fish Therapon jarbua. The result shows that the food pellets of the body wall were less toxic and more palatable than the gonads, viscera and cuvierian gland (p<0.001).

Central cancellation of self-produced tickle sensation

A self-produced tactile stimulus is perceived as less ticklish than the same stimulus generated externally. We used fMRI to examine neural responses when subjects experienced a tactile stimulus that was either self-produced or externally produced. More activity was found in somatosensory cortex when the stimulus was externally produced. In the cerebellum, less activity was associated with a movement that generated a tactile stimulus than with a movement that did not. This difference suggests that the cerebellum is involved in predicting the specific sensory consequences of movements, providing the signal that is used to cancel the sensory response to self-generated stimulation.

Reservoir fishery resources of south-east Asia

Although the reservoir area in south-east Asia is considerable, the fish production is low in the majority of reservoirs. Although high fish production has been recorded in a number of reservoirs in Sri Lanka and Indonesia, high fish production in reservoirs has with few exceptions resulted from the introduction of typical lake species from Africa. Addition of further lake fish species especially into deeper reservoirs will probably increase present fish yields. Diversification of the lake fish fauna can be achieved by introduction of species indigenous to the region like Etroplus suratensis. In this introduction of fish species, three points may be noted with specific reference to Tilapia spp.: (a) Lakes without indigenous cyprinids show marked fluctuation in fish catch with the introduction of Tilapia, and this could be stabilised by the introduction of predators and more diverse species. (b) Lakes with a moderate diversity of fish fauna show a high stabilised production with the introduction of Tilapia, presumably because of the effect of predator pressure on excessive Tilapia breeding. (c) Lowland lakes with a rich diversity of indigenous fish species colonising lakes may not require the introduction of Tilapia. Introduction of invertebrates into reservoirs in south east-Asia has not been done deliberately so far. However, the experience in other parts of the world, notably the Soviet Union, indicates that such introductions are likely to prove beneficial and to increase fish production. The potential for a considerable increase in fish production from reservoirs exists in south-east Asia. Proper management is likely to cost less than what is required for fish culture. Rural areas are likely to benefit most from increased fish production in reservoirs, and this might be a way to provide cheap protein where it is most urgently needed.

Study of the rocky intertidal communities of central and northern California: Years III and IV

The study objectives are to describe seasonal and successional variation in rocky intertidal community structure; determine the response of rocky intertidal communities to natural and human-induced disturbances and correlate these responses with successional, seasonal, and latitudinal variation; and correlate life history information and oil toxicity data with data from this and other relevant studies. The Year III and IV report is for the third (1987) and fourth (1988) years of a five-year field experimental study investigating two biological assemblages, the Mytilus assemblage and the Endocladia/Mastocarpus papillatus assemblage, that are being studied at six sites along the California coast. Volume I includes the report, Appendix A, and Appendix B. Volume II includes Appendix C. Volume III includes Appendix D. Volume IV includes Appendix E and Appendix F. Volume V includes Appendix G, Appendix H, and Appendix I.

African origin of modern humans in East Asia: A tale of 12,000 Y chromosomes

To test the hypotheses of modern human origin in East Asia, we sampled 12,127 male individuals from 163 populations and typed for three Y chromosome biallelic markers (YAP, M89, and M130). All the individuals carried a mutation at one of the three sites.

Y chromosome evidence of earliest modern human settlement in East Asia and multiple origins of Tibetan and Japanese populations

Background: The phylogeography of the Y chromosome in Asia previously suggested that modern humans of African origin initially settled in mainland southern East Asia, and about 25,000 30,000 years ago, migrated northward, spreading throughout East Asia. H

Winter Temperature and UV Are Tightly Linked to Genetic Changes in the p53 Tumor Suppressor Pathway in Eastern Asia

The tumor suppressor p53 is a master sensor of stress. Two human-specific polymorphisms, p53 codon 72 and MDM2 SNP309, influence the activities of p53. There is a tight association between cold winter temperature and p53 Arg72 and between low UV intensity

Global distribution of Y-chromosome haplogroup C reveals the prehistoric migration routes of African exodus and early settlement in East Asia

The regional distribution of an ancient Y-chromosome haplogroup C-M130 (Hg C) in Asia provides an ideal tool of dissecting prehistoric migration events. We identified 465 Hg C individuals out of 4284 males from 140 East and Southeast Asian populations. We genotyped these Hg C individuals using 12 Y-chromosome biallelic markers and 8 commonly used Y-short tandem repeats (Y-STRs), and performed phylogeographic analysis in combination with the published data. The results show that most of the Hg C subhaplogroups have distinct geographical distribution and have undergone long-time isolation, although Hg C individuals are distributed widely across Eurasia. Furthermore, a general south-to-north and east-to-west cline of Y-STR diversity is observed with the highest diversity in Southeast Asia. The phylogeographic distribution pattern of Hg C supports a single coastal 'Out-of-Africa' route by way of the Indian subcontinent, which eventually led to the early settlement of modern humans in mainland Southeast Asia. The northward expansion of Hg C in East Asia started similar to 40 thousand of years ago (KYA) along the coastline of mainland China and reached Siberia similar to 15 KYA and finally made its way to the Americas. Journal of Human Genetics (2010) 55, 428-435; doi:10.1038/jhg.2010.40; published online 7 May 2010

Genetic studies of human diversity in East Asia

East Asia is one of the most important regions for studying evolution and genetic diversity of human populations. Recognizing the relevance of characterizing the genetic diversity and structure of East Asian populations for understanding their genetic his

Cytogenetics, morphology and evolution of four subspecies of the Giant Sheep argali (Ovis ammon) of Asia

Dalai-lamae (Ovis ammon dalai-lamae), Gobi (O. a. darwini), Kara Tau (O. a. nigrimontana) and Tibetan (O. a. hodgsoni) argali share a 2n = 56 diploid chromosome number and a karyotype consisting of 2 pairs of biarmed and 25 pairs of acrocentric autosomes, a large acrocentric X and a minute Y chromosome. The Giemsa-banding patterns of the largest pair of biarmed chromosomes were identical to those of the largest biarmed chromosomes in all wild sheep and domestic sheep of the genus Ovis. The banding patterns of the second pair of biarmed chromosomes (metacentric) were identical to the third pair of biarmed chromosomes in Ovis with 2n = 54 and to the third largest pair of chromosomes in the 2n = 52 karyotype of Siberian snow sheep (O. nivicola). The G-banded karyotypes of dalai-lamae, darwini, hodgsoni and nigrimontana are consistent with all subspecies of argali (O. ammon), except that the Y chromosome is acrocentric instead of metacentric as typical of the argaliform wild sheep and Ovis. The Dalai-lamae and Tibetan argali specimens exhibit the light-colored, long-haired ruffs and body coloration typical of argalis from the Tibetan Plateau. The Gobi argali, from the extreme western Gobi, is similar to the dark phase argali.

Pitfalls in the analysis of ancient human mtDNA

The retrieval of DNA from ancient human specimens is not always successful owing to DNA deterioration and contamination although it is vital to provide new insights into the genetic structure of ancient people and to reconstruct the past history. Normally, only short DNA fragments can be retrieved from the ancient specimens. How to identify the authenticity of DNA obtained and to uncover the information it contained are difficult. We employed the ancient mtDNAs reported from Central Asia (including Xinjiang, China) as an example to discern potentially extraneous DNA contamination based on the updated mtDNA phylogeny derived from mtDNA control region, coding region, as well as complete sequence information. Our results demonstrated that many mtDNAs reported are more or less problematic. Starting from a reliable mtDNA phylogeney and combining the available modern data into analysis, one can ascertain the authenticity of the ancient DNA, distinguish the potential errors in a data set, and efficiently decipher the meager information it harbored. The reappraisal of the mtDNAs with the age of more than 2000 years from Central Asia gave support to the suggestion of extensively (pre)historical gene admixture in this region.

Evolutionary history of the mtDNA 9-bp deletion in Chinese populations and its relevance to the peopling of east and southeast Asia

In total, 1218 Chinese from twelve ethnic groups and nine Han geographic groups were screened for the mtDNA 9-bp deletion motif. The frequency of the 9-bp deletion in all samples was 14.7% but ranged from 0% to 32% in the various ethnic groups. Three individuals had a triplication of the 9-bp segment. Phylogenetic and demographic analyses of the mtDNA hypervariable segment 1 (HVS1) sequences suggest that the 9-bp deletion occurred more than once in China. The majority of the Chinese deletion:haplotypes (about 90%) have a common origin as a mutational event following an initial expansion of modem humans in eastern Asia. Other deletion haplotypes and the three haplotypes with a 9-bp triplication may have arisen independently in the Chinese, presumably by replication error. HVS1 haplotype analysis suggests two possible migration routes of the 9-bp deletion in east and southeast Asia. Both migrations originated in China with one route leading to the Pacific Islands via Taiwan, the other to southeast Asia and possibly the Nicobar Islands. Along both routes of peopling, a decrease in HVS1 diversity of the mtDNA haplotypes is observed. The "Polynesian motif (16217T/C, 16247A/G, and 16261C/T)" and the 16140T/C, 16266C/A, or C/G polymorphisms appear specific to each migration route.

Molecular systematics of Xenocyprinae (Teleostei : Cyprinidae): Taxonomy, biogeography, and coevolution of a special group restricted in east Asia

We surveyed mitochondrial DNA (mtDNA) sequence variation in the subfamily Xenocyprinae from China and used these data to estimate intraspecific, interspecific, and intergeneric phylogeny and assess biogeographic scenarios underlying the geographic structu

Molecular phylogeny of wood mice (Apodemus, Muridae) in East Asia

Sequences of the mitochondrial cytochrome b (1140 bp) and nuclear IRBP (1152 bp) genes were used to assess the evolutionary history of Apodemus, using the complete set of Asian species. Our results indicate that speciation in Asia involved three radiations, which supports an earlier study. The initial radiation yielded A. argenteus (Japanese endemic), A. gurkha (Nepalese endemic), and the ancestral lineage of the remaining Asian species. This lineage subsequently diverged into four groups: agrarius-chevrieri (agrarius group), draco-latronum-semotus (draco group), A. peninsulae, and A. speciosus (Japanese endemic). The final step consisted of divergence within two species groups as a consequence of the geography of the Yunnan-Guizhou plateau and Taiwan. The ecological ability of two Apodemus-species to inhabit one locality via niche partitioning likely drove the second radiation and shaped the basic geographical pattern seen today: A. argenteus and A. speciosus in Japan, A. agrarius and A. peninsulae in northern China, and the A. agrarius and A. draco groups in southern China. The three radiations are estimated to have occurred 7.5, 6.6, and 1.8-0.8 Mya respectively, using the IRBP clock, based on rat-mouse divergence 12 Mya. (C) 2003 The Linnean Society of London.