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1.
We sampled Palaearctic naked‐toed geckos from across their range in India and used two mitochondrial and two nuclear genes to reconstruct relationships within a global phylogeny. Published sequences of Peninsular Indian Hemidactylus allow us to contrast these two groups in dating analyses – providing insights into the history of the Indian dry zone. Palaearctic naked‐toed geckos first moved onto the Indian Plate in the Oligocene, with higher‐level diversification probably linked to collision of the Indian and Eurasian plates, and subsequent dispersal into‐India and diversification with increasing Miocene aridity. An independent gekkonid radiation with species in the dry zone, Hemidactylus diversified during the same period in Peninsular India. Our results demonstrate that dry zone taxa across India may date back to at least the Miocene, with a potential historical climatic barrier between the Indus and Peninsular Indian Divisions. ‘Cyrtopodionaravallense is revealed to be a complex with seven genetically and environmentally divergent lineages that began diversifying in the late Miocene, congruent with increased aridity in north‐western India. This discovery of cryptic diversity in the Indian dry zone represents the first terrestrial vertebrate radiation from north‐western central India and highlights how little we understand of the regions’ biodiversity, emphasizing the need for systematic geographic sampling and multiline evidence to reveal true patterns of diversity. The ancestor of ‘Cyrtopodion’ aravallense came into the nascent Indian dry zone in the Miocene and has since diversified, potentially in the absence of any sympatric scansorial rupicolous geckos. Cyrtopodion scabrum represents a unique case of commensalism and shows phylogeographic structure in its presumed native range. The taxonomic implications of our study include a number of undescribed species, recognition of ‘Cyrtopodion’ as a distinct lineage and the non‐monophyly of Altiphylax.  相似文献   

2.
This article examines ‘Asian electronic music’, a generally progressive diasporic South Asian scene which fuses electronic dance music beats with instruments/sounds traditionally associated with the subcontinent, and how it became embedded into ‘majoritarian’ Indian nationalism. In India, the music's perceived ‘fusion’ aesthetic became emblematic of an emergent India which was economically prosperous while ‘respecting’ its cultural heritage. Using the case of an album which remixed India's national song, Vande Mataram, this article explores the convergences and divergences between Asian electronic musicians in Delhi and Hindu nationalists. The article concludes that the musicians in Delhi did not lend to Hindu nationalism. However, they perhaps gave secular Indian nationalism a ‘cool’ gloss. Ultimately, the production and consumption of Asian electronic music in Delhi raises significant questions regarding the scene's relationship to Indian nationalisms.  相似文献   

3.
The biogeographic and tectonic history of India   总被引:10,自引:0,他引:10  
Aim To present an up to date account of the Mesozoic history of India and its relationship to the other Gondwana continents and to Eurasia. Location Continents surrounding the Western Indian Ocean. Methods Utilization of recent evidence of continental relationships based upon research in stratigraphy, palaeomagnetism, palaeontology, and contemporary biotas. Results The physical data revealed a sequence of events as India moved northward: (1) India–Madagascar rifted from east Africa 158–160 Ma (million years ago), (2) India–Madagascar from Antarctica c. 130 Ma, (3) India–Seychelles from Madagascar 84–96 Ma, (4) India from Seychelles 65 Ma, (5) India began collision with Eurasia 55–65 Ma and (6) final suturing took place c. 42–55 Ma. However, data from fossil and contemporary faunas indicate that, throughout the late Cretaceous, India maintained exchanges with adjacent lands. There is an absence in the fossil record of peculiar animals and plants that should have evolved, had India undergone an extended period of isolation just before its contact with Eurasia. Main conclusions The depiction of India in late Cretaceous as an isolated continent is in error. Most global palaeomaps, including the most recent one, show India, as it moves northward, following a track far out in the Indian Ocean. But the evidence now indicates that India's journey into northern latitudes cannot have taken place under such isolated circumstances. Although real breaks among the lands were indicated by the physical data, faunal links were maintained by vagile animals that were able to surmount minor marine barriers. India, during its northward journey, remained close to Africa and Madagascar even as it began to contact Eurasia.  相似文献   

4.
This study sought to reconstruct the history of Lantana invasion and spread in India by considering two questions; (a) from where, by who, and when were Lantana species introduced into India? and (b) given its long history in the country, is it still spreading or more or less stable? We critically evaluated the archival and historical information on plant imports by the European powers into India during the period before and after British colonization. We then reconstructed the path of spread by analyzing the spatio-temporal patterns of occurrence and distribution of Lantana in India at both the national and local scale using a GIS platform. The spread of Lantana across the globe started as early as the 1690s. The European colonial powers moved the plants from Latin America to Europe and to their colonial countries in the early 1800s. Lantana species were introduced in India from 1807 onwards and thereafter the colonial powers moved this plant across the country. Following its introduction into India, the spread of Lantana across the country, either through subsequent multiple introductions from Europe to different British cantonments, or through moving the plants between cantonments within India, were reasonably rapid spanning only a few decades. In the absence of a rigorous control program, the spread of Lantana has gone on unabated and thereby impacting both wildlife and biodiversity.  相似文献   

5.
Summary English, Italian (including Sardinian), and Spanish populations from Europe and Muslim, Hindu, Sikh, Punjabi, and other populations from the Indian subcontinent currently living either in Birmingham or in India were screened for electrophoretically detectable genetic variants of red cell glyoxalase I (GLO), and their frequencies were reported. All the western European populations investigated, including those reported, exhibited an incidence of close to 44% for the GLO 1 gene. The frequency distribution of the GLO 1 gene in various populations from the Indian subcontinent, in contrast, was found to range between 0.15 and 0.33. These observations suggest that the European populations in general are genetically more homogeneous than are the populations of the Indian subcontinent.  相似文献   

6.
Maximum accumulation of ergosterol by Rhodotorula glutinis IIP-30 [4% (w/w) of the biomass] was at pH 4 and 28 to 30°C, wich glucose or sucrose as carbon source and (NH4)2SO4 as N-source. Molasses only gave 1% (w/w) ergosterol content, as did KNO3 or urea when used as sole N source.V.W. Johnson was and N.K. Yadav is with the Microbiology Department, School of Science, Gujarat University, Ahmedabad 380 009, India. V.W. Johnson is now with the Blotechnology Laboratory, Research Centre, Gujarat State Fertillizers Company Ltd, Baroda 391 750, India. M. Singh was with the Applied Biology Laboratory, Research Centre, Indian Petrochemicals Corporation Ltd, Baroda 391 345, India, and is now with Pfizer Limited, 178, Industrial Area, Chandigarh 160 002, India.  相似文献   

7.
The trade in live animals between India and Brazil dates from the late nineteenth century when European travellers traded animals of Indian origin for display in zoos. Considering the origin of coffee and sugar cane, as well as the expertise related to mineral evaluation, we need to consider that India was involved in important economic cycles of Brazil, even indirectly. This virtuous flow of trade has been maintained and intensified throughout modern history, especially after these two nations gained political independence from their colonisers, thereby becoming independent in mercantile affairs. This paper addresses the main points related to the use of animals of Indian origin in Brazil. We revisit some of the historical aspects of the process of colonisation of Brazil, as well as the importation of animals from India. The restrictions imposed on this process due to the occurrence of diseases in cattle and buffalo in India will be examined. At the end of the text, emphasis will be given to the risks of introducing exotic diseases into Brazil.  相似文献   

8.
The human malaria parasite Plasmodium vivax is globally widespread, causing high malaria morbidity. As P. vivax is highly endemic to India, and previous reports indicate genetic homogeneity in population samples, we tested the hypothesis of no genetic structuring in Indian P. vivax. Further, based on the reports of increasing incidence of Plasmodium falciparum infection in comparison with P. vivax in recent years in India, it was important to understand whether reduction in population size has resulted in decrease in P. vivax infection rate in India. For this, we utilized recently developed putatively neutral markers from chromosome 13 of P. vivax to score single nucleotide polymorphisms in 126 P. vivax isolates collected from 10 different places in India. The overall results indicated that Indian P. vivax bears high nucleotide diversity within population samples but moderate amount of genetic differentiation between population samples. STRUCTURE analysis grouped 10 population samples into three clusters based on the proportion of the genetic ancestries in each population. However, the pattern of clustering does not correlate with sampling locations in India. Furthermore, analyses of past demographic events indicated reduction in population size in majority of population samples, but when isolates from all the 10 samples were considered as a single population, the data fit to the demographic equilibrium model. All these observations clearly indicate that Indian P. vivax presents complex evolutionary history but possesses several features of being a part of ancestral distribution range of this species.  相似文献   

9.
The HLA system may play an important role in natural selection processes through its involvement in immune response and because of the HLA association of some diseases. Linkage disequilibrium in the HLA system poses many interesting questions. India. a melting pot of races and cultures in sympatric isolation, provides an ideal opportunity to study these aspects. Linkage disequilibrium and haplotype data are valuable in the comparison of various populations. An analysis of the available HLA A-B haplotype data for the Indian population documents the heterogeneous nature of the latter: each endogamous caste group, major group or even regional group has its characteristic haplotype profile. The haplotypeA1-B17 is present in most Indian populations butA10-B8 occurs mostly in North India: this may be a consequence of founder effects. The haplotypeAl-B8 a typical Caucasian haplotype, is absent in the Indian subcontinent: this may be due to the selective disadvantageA1-B8 confers in the Indian environment. The different regional and caste groups of India possessing diverse haplolype combinations provide an ideal opportunity to evaluate the selective values of these haplotypes and to study human immunogenetics.  相似文献   

10.
The golden jackal (Canis aureus) is one of the most common and widely distributed carnivores in India but phylogeographic studies on the species have been limited across its range. Recent studies have observed absence of mitochondrial (mt) DNA diversity in European populations while some North African populations of golden jackal were found to carry gray wolf (Canis lupus lupaster) mtDNA lineages. In the present study, we sequenced 440 basepairs (bp) of control region (CR) and 412 bp of cytochrome b (cyt b) gene of mtDNA from 62 golden jackals sampled from India (n = 55), Israel (n = 2) and Bulgaria (n = 5), to obtain a total of eighteen haplotypes, comprising sixteen from India and one each from Israel and Bulgaria. Except for three previously described haplotypes represented by one cyt b and one CR haplotype both from India, and one CR haplotype from Bulgaria, all haplotypes identified in this study are new. Genetic diversity was high in golden jackals compared to that reported for other canids in India. Unlike the paraphyletic status of African conspecifics with the gray wolf, the Indian (and other Eurasian) golden jackal clustered in a distinct but shallow monophyletic clade, displaying no evidence of admixture with sympatric and related gray wolf and domestic dog clades in the region. Phylogeographic analyses indicated no clear pattern of genetic structuring of the golden jackal haplotypes and the median joining network revealed a star-shaped polytomy indicative of recent expansion of the species from India. Indian haplotypes were observed to be interior and thus ancestral compared to haplotypes from Europe and Israel, which were peripheral and hence more derived. Molecular tests for demographic expansion confirmed a recent event of expansion of golden jackals in the Indian subcontinent, which can be traced back ~ 37,000 years ago during the late Pleistocene. Our results suggest that golden jackals have had a potentially longer evolutionary history in India than in other parts of the world, although further sampling from Africa, the Middle East and south-east Asia is needed to test this hypothesis.  相似文献   

11.
Perspectives of diverse constituencies need to be incorporated when developing conservation strategies. In Menri (Medicine Mountains) of the Eastern Himalayas, Tibetan doctors and professional botanists were interviewed about conservation of useful plants. We compare these two perspectives and find they differ significantly in conservation priorities (Wilcoxon Signed Ranks P < 0.05), both in how they prioritized, as well as the priorities themselves. Tibetan doctors first consider which plants are most important to their medical practice and, then secondarily, the conservation status of these plants. Additionally, perceptions of threatened medicinal plants differ among Tibetan doctors who received medical training in Lhasa, who were local trained, and who were self-taught. In contrast, professional botanists came to a consensus among themselves by first considering the conservation status of plants and then considering use. We conclude that, in order to effect community based conservation, opinions from both Tibetan doctors and professional botanists should be considered in establishing conservation priorities and sustainable conservation programs. Furthermore, we set our own research agenda based on combined perspectives.  相似文献   

12.
Reintroducing megafauna to their historic range is an effective strategy to halt their extinctions and restore ecosystems. Wild water buffalo (Bubalus arnee) is an endangered megaherbivore that is lost from 95% of its range. About 90% of its global population (less than 4000) resides within India, in two isolated populations: northeast and central India. The central Indian population is on the verge of extinction and warrants urgent conservation interventions. We assess the potential and provide a strategy for reintroducing buffaloes in Kanha National Park, India. Habitat suitability using the global occurrence of buffalo revealed low-lying grasslands with least human pressure found in Kanha (390 km2) to be suitable. Within this suitable range, we evaluated vegetation composition, forage biomass, and potential carrying capacity. Multidimensional ordination classified these suitable sites into moist and dry grassland clusters. Moist grasslands were found to better suit reintroduction due to lower grazing pressure, higher productivity, and availability of perennial water sources. Distinct matriarchal clades of swamp and river buffalo were observed. Within the river buffalo clade, Indian wild buffaloes formed a distinct cluster with close proximity between northeast and central Indian samples, suggesting northeast buffaloes could be sourced for a founding population in Kanha. Following IUCN guidelines, we discuss the reintroduction strategy that could sustain approximately 200 buffaloes in the area and subsequently expand to other suitable habitats in central India. If implemented as proposed, recovery of this lost ecosystem engineer will help to restore grasslands, and swamp habitats, as well as contribute to its global conservation efforts.  相似文献   

13.
This article focuses on the political struggles between Hindu and Muslim Indian immigrant groups in the United States over the definition of "Indianness". Hindu Indian American organizations define India as a Hindu society and are strong supporters of the Hindu nationalist movement in India. Muslim Indian American organizations, on the other hand, view India as a multi-religious and multicultural society. They are striving to safeguard India's secularism and towards this end, have entered into coalitional relationships with lower caste groups. Both types of organizations are working to influence American and Indian politics in line with their respective interests, leading to an exacerbation of the conflict between the two immigrant groups. This article examines the reasons for this development and its implications, both for the development of an Indian American community in the United States and for religion and politics in India.  相似文献   

14.
Indigenous cattle of India belong to the species, Bos indicus and they possess various adaptability and production traits. However, little is known about the genetic diversity and origin of these breeds. To investigate the status, we sequenced and analyzed the whole mitochondrial DNA (mtDNA) of seven Indian cattle breeds. In total, 49 single-nucleotide variants (SNVs) were identified among the seven breeds analyzed. We observed a common synonymous SNV in the COII gene (m.7583G?>?A) of all the breeds studied. The phylogenetic analysis and genetic distance estimation showed the close genetic relationship among the Indian cattle breeds, whereas distinct genetic differences were observed between Bos indicus and Bos taurus cattle. Our results indicate a common ancestor for European Zwergzebu breed and South Indian cattle. The estimated divergence time demonstrated that the Bos indicus and Bos taurus cattle lineages diverged 0.92 million years ago. Our study also demonstrates that ancestors of present zebu breeds originated in South and North India separately ~30,000 to 20,000 years ago. In conclusion, the identified genetic variants and results of the phylogenetic analysis may provide baseline information to develop appropriate strategies for management and conservation of Indian cattle breeds.  相似文献   

15.
Cynocephalid dermopterans (flying lemurs) are represented by only two living genera (Cynocephalus and Galeopterus), which inhabit tropical rainforests of South‐East Asia. Despite their very poor diversity and their limited distribution, dermopterans play a critical role in higher‐level eutherian phylogeny inasmuch as they represent together with Scandentia (tree‐shrew) the sister group of the Primates clade (Plesiadapiformes + Euprimates). However, unlike primates, for which the fossil record extends back to the early Palaeogene on all Holarctic continents and in Africa, the evolutionary history of the order Dermoptera sensu stricto (Cynocephalidae) has so far remained undocumented, with the exception of a badly preserved fragment of mandible from the late Eocene of Thailand (Dermotherium major). In this paper, we described newly discovered fossil dermopterans (essentially dental remains) from different regions of South Asia (Thailand, Myanmar, and Pakistan) ranging from the late middle Eocene to the late Oligocene. We performed microtomographic examinations at the European Synchrotron Radiation Facility (ESRF, Grenoble, France) to analyse different morphological aspects of the fossilized jaws. The abundant material from the late Oligocene of Thailand (Nong Ya Plong coal mine) allows us to emend the diagnosis of the genus Dermotherium and to describe a new species: Dermotherium chimaera sp. n. This species exhibits an interesting mosaic of plesiomorphic cynocephalid characters shared with Cynocephalus and Galeopterus, and as such, it probably documents a form close to the ancestral morphotype from which the two extant forms are derived (supported by cladistic assessment of the dental evidence). The discovery of Palaeogene cynocephalids is particularly significant since it attests to the great antiquity of the order Dermoptera in Asia, and besides, it provides the first spatio‐temporal glimpse into the evolutionary history of that enigmatic mammal group. In that respect, these fossils testify to a long history of endemism in South Asia for dermopterans, and demonstrate that their modern geographic restriction in south‐eastern Asia is clearly a relictual distribution. Cynocephalids had a more widespread distribution during the Palaeogene, which extended from the Indian subcontinent (the rafting Greater India) to South‐East Asia. Their subsequent extinction on the Indian subcontinent was probably mediated by the major palaeogeographic and geomorphologic events related to the India‐Eurasia collision (retreat of the Paratethys Sea, formation of orogenic highlands) that have strongly affected the climate of South Asia at the end of the Oligocene.  相似文献   

16.
Viable cells of H2-producers (Bacillus licheniformis and a mixed microbial culture) were immobilized on brick dust and in calcium alginate beads. In batch culture, cells of the mixed culture in the free state yielded 8.2 l H2/mol glucose utilized, whereasB. licheniformis evolved 13.1 l H2. Immobilized cells, however, gave 4-fold more H2 than the free bacteria. Highest yields were from the cells immobilized on brick dust. High H2-production rates continued over two rounds of re-use of the immobilized cells.A. Kumar, S.R. Jain and A.P. Joshi were and V. C. Kalia is with the Centre for Biochemical Technology (CSIR), University Campus, Mall Road, Delhi-110 007, India; C.B. Sharma is with the Department of Biosciences and Biotechnology, University of Roorkee, Roorkee-247 667, India. A. Kumar is now with the Biochemistry Laboratory, Department of Chemistry, Indian Institute of Technology, New Delhi-110 016, India, S.R. Jain is now with the Centre for Biomedical Engineering, Indian Institute of Technology, New Delhi-110 016, India, and A.P. Joshi is now with the Chemical Engineering Division, National Chemical Laboratory, Pune-411 008, India.  相似文献   

17.
18.
Utilization of multiple putatively neutral DNA markers for inferring evolutionary history of species population is considered to be the most robust approach. Molecular population genetic studies have been conducted in many species of Anopheles genus, but studies based on single nucleotide polymorphism (SNP) data are still very scarce. Anopheles minimus is one of the principal malaria vectors of Southeast (SE) Asia including the Northeastern (NE) India. Although population genetic studies with mitochondrial genetic variation data have been utilized to infer phylogeography of the SE Asian populations of this species, limited information on the population structure and demography of Indian An. minimus is available. We herewith have developed multilocus nuclear genetic approach with SNP markers located in X chromosome of An. minimus in eight Indian and two SE Asian population samples (121 individual mosquitoes in total) to infer population history and test several hypotheses on the phylogeography of this species. While the Thai population sample of An. minimus presented the highest nucleotide diversity, majority of the Indian samples were also fairly diverse. In general, An. minimus populations were moderately substructured in the distribution range covering SE Asia and NE India, largely falling under three distinct genetic clusters. Moreover, demographic expansion events could be detected in the majority of the presently studied populations of An. minimus. Additional DNA sequencing of the mitochondrial COII region in a subset of the samples (40 individual mosquitoes) corroborated the existing hypothesis of Indian An. minimus falling under the earlier reported mitochondrial lineage B.  相似文献   

19.
Cysticercosis, caused by Taenia solium larva is a major public health problem, especially in the developing world and neurocysticercosis (NCC) is considered to be the most common parasitic infestation of the central nervous system. NCC is identified as the single most common cause of community acquired active epilepsy; 26.3% to 53.8% active epilepsy cases in the developing world including India and Latin America are due to NCC. It is also becoming more common in the developed world because of increased migration of people with the disease or Taenia solium carriers and frequent travel to the endemic countries. It is estimated that three quarters of the estimated 50 million people with active epilepsy live in the poor countries of the world. Recent Indian studies using neuroimaging techniques suggest that the disease burden in India surpasses many other developing countries. Hence it is important to know the epidemiology, pathogenesis and diagnostic criteria so as to assess the disease burden and adopt interventional strategies for its control. Literature search was done for this review with special emphasis on Indian studies to create awareness about the disease in India, since cysticercosis is preventable and potentially eradicable.  相似文献   

20.
Seventy isolates of Fusarium oxysporum f.sp. ciceris (Foc) causing chickpea wilt representing 13 states and four crop cultivation zones of India were analysed for their virulence and genetic diversity. The isolates of the pathogen showed high variability in causing wilt incidence on a new set of differential cultivars of chickpea, namely C104, JG74, CPS1, BG212, WR315, KWR108, GPF2, DCP92‐3, Chaffa and JG62. New differential cultivars for each race were identified, and based on differential responses, the isolates were characterized into eight races of the pathogen. The same set of isolates was used for molecular characterization with four different molecular markers, namely random amplified polymorphic DNA, universal rice primers, simple sequence repeats and intersimple sequence repeats. All the four sets of markers gave 100% polymorphism. Unweighted paired group method with arithmetic average analysis grouped the isolates into eight categories at genetic similarities ranging from 37 to 40%. The molecular groups partially corresponded to the states of origin/chickpea‐growing region of the isolates as well as races of the pathogen characterized in this study. The majority of southern, northern and central Indian populations representing specific races of the pathogen were grouped separately into distinct clusters along with some other isolates, indicating the existence of variability in population predominated by a single race of the pathogen. The present race profiling for the Indian population of the pathogen and its distribution pattern is entirely new. The knowledge generated in this study could be utilized in resistance breeding programme. The existence of more than one race, predominated by a single one, in a chickpea cultivation zone as supported by the present molecular findings is also a new information.  相似文献   

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