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Ten compounds isolated from the extract of the central Asian lichens comprised new glycosides and glycoside esters having 18R-hydroxy-dihydroalloprotolichesterinic, 18S-hydroxy-dihydroprotolichesterinic and 18S-hydroxy-neodihydroprotolichesterinic acids, as the aglycones and a saccharide moiety linked at C-18 and also at C-21 made by glucose, xylose or rhamnose. The structures were elucidated using extensive spectroscopic analysis (1D and 2D NMR, MS, IR, UV and ORD) and by biochemical methods. 相似文献
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The composition of two bromoallenic aliphatic fatty acids obtained from lichens collected around Lake Issyk-Kul (central Asia) is described. These compounds were identified by means of 1H and 13C NMR, MS and IR spectra. 相似文献
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Cenozoic bird tracks are known largely from North America, Europe, and the Middle East. There have been no reports of Cenozoic bird tracks from East Asia. This paper describes a series of two trackways produced by a galliform-like or gruiform-like bird from the Oligocene to Early Miocene of Tibet. The tracks are represented by tracings collected from a coal mine in Shigatse, Tibet, during the late 1970s. The tracks are comparable to Ornithoformipes and Pavoformipes and likely represent a medium-sized to large cursorial or flightless bird. In relation to modern bird tracks, the tracks bear a striking resemblance to those produced by the North American Wild Turkey (Meleagris gallopavo) except that M. gallopavo tracks often possess a small, elevated hallux impression. Due to the fact that these are tracings, however, a hallux may have been present and simply have been overlooked. The Shigatse trackways were, unfortunately, lost when the mine was closed and then backfilled during the 1980s, and there is little to no likelihood of recovery. Casts can be catalogued as holotype specimens but tracings cannot; however, all the original tracings have been donated to a public institution by their discoverer, Yimin Wu. 相似文献
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Novel brominated lipidic compounds from lichens of central Asia. 总被引:1,自引:0,他引:1
The composition of novel brominated aliphatic compounds from lichens collected during summer from stones around the lake Issyk-Kul (Central Asia) is described. The compounds, predominantly fatty acid derivatives with unique groups (bromine, cyclopropane, oxirane) and conjugated double and triple bonds, were identified by means of 1H and 13C-NMR, MS, IR and UV spectra. 相似文献
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Gerald Mayr 《Zoologica scripta》2011,40(5):448-467
Mayr, G. (2011) Cenozoic mystery birds – on the phylogenetic affinities of bony‐toothed birds (Pelagornithidae). —Zoologica Scripta, 40, 448–467. The extinct Cenozoic bony‐toothed birds (Pelagornithidae) are characterized by the occurrence of unique spiky projections of the osseous jaws and are among the most distinctive neornithine taxa. Earlier authors considered these marine birds to be most closely related to ‘Pelecaniformes’ or Procellariiformes, but recent phylogenetic analyses resulted in a sister group relationship to Anseriformes. This latter hypothesis was, however, coupled with a non‐monophyly of galloanserine or even neognathous birds, which is not supported by all other current analyses. The character evidence for anseriform affinities of pelagornithids is thus reassessed, and it is detailed that the alleged apomorphies cannot be upheld. Pelagornithids lack some key apomorphies of galloanserine birds, and analysis of 107 anatomical characters did not support anseriform affinities, but resulted in a sister group relationship between Pelagornithidae and Galloanseres. By retaining a monophyletic Galloanseres, this result is in better accordance with widely acknowledged hypotheses on the higher‐level phylogeny of birds. The (Pelagornithidae + Galloanseres) clade received, however, only weak bootstrap support, and some characters, such as the presence of an open frontoparietal suture, may even support a position of Pelagornithidae outside crown‐group Neognathae. 相似文献
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Guo P Liu Q Xu Y Jiang K Hou M Ding L Pyron RA Burbrink FT 《Molecular phylogenetics and evolution》2012,63(3):825-833
Based on a combination of six mitochondrial gene fragments (12S RNA, cyt b, ND1, ND2, ND4 and CO1) and one nuclear gene (c-mos) from 22 genera we infer phylogenetic relationships among natricine snakes and examine the date and area of origin of these snakes. Our phylogenetic results indicate: (1) the subfamily Natricinae is strongly supported as monophyletic including a majority of extant genera, and a poorly known and previously unassigned species Trachischium monticola, (2) two main clades are inferred within Natricinae, one containing solely taxa from the Old World (OW) and the other comprising taxa from a monophyletic New World (NW) group with a small number of OW relatives. Within the first clade, the genera Xenochrophis and Amphiesma are apparently not monophyletic. Divergence dating and ancestral area estimation indicate that the natricines originated in tropical Asia during the later Eocene or the Oligocene. We recover two major dispersals events out of Asia, the first to Africa in the Oligocene (28 Ma) and the second to the Western Palearctic and the New World at 27 Ma. This date is consistent with the dispersal of numerous other OW groups into the NW. 相似文献
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High-resolution analysis of Y-chromosomal polymorphisms reveals signatures of population movements from central Asia and West Asia into India 总被引:6,自引:0,他引:6
Linguistic evidence suggests that West Asia and Central Asia have been the two major geographical sources of genes in the
contemporary Indian gene pool. To test the nature and extent of similarities in the gene pools of these regions we have collected
DNA samples from four ethnic populations of northern India, and have screened these samples for a set of 18 Y-chromosome polymorphic
markers (12 unique event polymorphisms and six short tandem repeats). These data from Indian populations have been analysed
in conjunction with published data from several West Asian and Central Asian populations. Our analyses have revealed traces
of population movement from Central Asia and West Asia into India. Two haplogroups, HG-3 and HG-9, which are known to have
arisen in the Central Asian region, are found in reasonably high frequencies (41.7% and 14.3% respectively) in the study populations.
The ages estimated for these two haplogroups are less in the Indian populations than those estimated from data on Middle Eastern
populations. A neighbour-joining tree based on Y-haplogroup frequencies shows that the North Indians are genetically placed
between the West Asian and Central Asian populations. This is consistent with gene flow from West Asia and Central Asia into
India. 相似文献
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A new family, Brodavidae, with one new genus and four species, is described from the Late Cretaceous (Maastrichtian) of Asia and North America. These include the first freshwater occurrences and latest records of the order Hesperornithiformes, an extinct group of diving birds whose marine members had probably lost their powers of flight by the end of the Early Cretaceous. Minimal pachyostosis in the freshwater form suggests the possibility of volant abilities. 相似文献
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He Wang Suryendu Dutta Richard S. Kelly Arka Rudra Sha Li Qing-Qing Zhang Qian-Qi Zhang Yi-Xiao Wu Mei-Zhen Cao Bo Wang Jian-Guo Li Hai-Chun Zhang 《Palaeoworld》2018,27(4):506-513
The palaeoenvironmental reconstruction of central Tibet is key to understanding the uplift history of the Tibetan Plateau, which had a profound influence on Cenozoic global climate and biotic change. Here we report an amber layer from the lower part of the Dingqing Formation (late Oligocene) in Lunpola of central Tibet, which is the first record of amber from Tibet. Herein we find that Lunpola amber is derived from dipterocarp trees, as determined by gas chromatography-mass spectrometry, which are restricted to and dominant in Asian rainforest nowadays. This amber forest represents the northernmost dipterocarp forest and is consistent with the hypothesis of out-of-India dispersal of Asian dipterocarps. The Lunpola amber most probably was derived from the lower part of the Niubao Formation (early–middle Eocene) and suggests a tropical/subtropical wet forest was present in central Tibet at least before the late Oligocene (probably early–middle Eocene). 相似文献
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Biological Invasions - Nosema ceranae is believed to have been originally a parasite of the Asian honey bee, Apis cerana, in East Asia that later infected the Western honey bee, Apis mellifera,... 相似文献
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《Comptes Rendus Palevol》2016,15(7):877-887
The Tertiary sediments of northern Pakistan are an exceptional record of terrestrial sedimentation and represent most of Neogene time. Foremost is the Siwalik Group of the Potwar Plateau, for which multiple, superposed fossil levels span ∼18–6 Ma. Well-developed magnetostratigraphic control provides secure dating so that Siwalik fossil horizons may be interpolated into a time scale with resolution to 100,000 years. We describe the geographic setting of the Potwar, give an overview of the temporal distribution of faunas, and discuss changes in paleohabitat and paleoecology with coinciding faunal change, as seen from the Siwalik viewpoint. The long Siwalik biostratigraphy of many successive assemblages with its resolved time scale may be compared directly with other well-dated sequences. Immigrant arrival and timing of faunal change may be traced. The basins of the Iberian Peninsula show somewhat different timing of introduction of hipparionine horses, and faunal turnover in the Siwaliks clearly precedes the Vallesian crisis in Spain. In contrast to the increasingly seasonal precipitation of the late Miocene Potwar, the paleohabitat of coeval North China appears to have been moist and equable, with high diversity faunas. Continued development and comparison of resolved Neogene records allow increasing resolution of the patterns of faunal change on regional to global levels. 相似文献
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Analysis of the available data on the findings and taxonomical structure of caddisflies (Insecta, Trichoptera) in the Cenozoic fossil resins of Europe shows that there are four European amber regions (Baltic, Rovno, Saxonian, and Danish) are characterized by a relatively abundant trichopteran fauna, comprising 27 families, 72 genera, and 256 species. These faunas show the dominance of Psychomyioidea (families Polycentropodidae, Psychomyiidae, and Ecnomidae) with Polycentropodidae comprising up to 75% of all records. The amber faunas are second in the dominance of Polycentropodidae only to the terminal Eocene of Florissant (84% of Polycentropodidae). No modern caddisfly species have been found. The amber regions are significantly different in the species composition of Trichoptera although the generic and family structures are similar. Comparison with the modern faunas of Europe shows the absence of advanced Limnephilidae, which are characteristic of the Holocene faunas of Europe, and the rarity of recently abundant Hydropsychidae and Hydroptilidae. The overall composition of amber Trichoptera suggests that it is structurally related to the faunas of Caucasus and Southeastern Asia and might be evidence of seasonally low-contrast (equable) climate in the Late Eocene of Europe. 相似文献
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Chaix R Quintana-Murci L Hegay T Hammer MF Mobasher Z Austerlitz F Heyer E 《Current biology : CB》2007,17(1):43-48
Pastoral and farmer populations, who have coexisted in Central Asia since the fourth millennium B.C., present not only different lifestyles and means of subsistence but also various types of social organization. Pastoral populations are organized into so-called descent groups (tribes, clans, and lineages) and practice exogamous marriages (a man chooses a bride in a different lineage or clan). In Central Asia, these descent groups are patrilineal: The children are systematically affiliated with the descent groups of the father. By contrast, farmer populations are organized into families (extended or nuclear) and often establish endogamous marriages with cousins. This study aims at better understanding the impact of these differences in lifestyle and social organization on the shaping of genetic diversity. We show that pastoral populations exhibit a substantial loss of Y chromosome diversity in comparison to farmers but that no such a difference is observed at the mitochondrial-DNA level. Our analyses indicate that the dynamics of patrilineal descent groups, which implies different male and female sociodemographic histories, is responsible for these sexually-asymmetric genetic patterns. This molecular signature of the pastoral social organization disappears over a few centuries only after conversion to an agricultural way of life. 相似文献
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Migratory ducks, Canada geese, and sandhill crane from the Pacific North American Flyway have been screened for Campylobacter spp. Samples (298) from these birds were examined and the incidence of Campylobacter spp. in the samples were as follows: sandhill crane (Grus canadensis tabida), 81%; ducks (Aythya collaris, Anas carolinensis, Aythya americana, and Anas platyrhynchos), 73%; and Canada geese (Branta canadensis), 5%. All isolates were identified as Campylobacter jejuni. To our knowledge this is the first report of the isolation of C. jejuni from sandhill crane. The high frequency of isolation in both the sandhill crane and migratory ducks indicated that these bird populations may play a significant role in the dissemination of the bacterium. Because of their migratory habits, these birds may be particularly important in spreading C. jejuni to remote areas. 相似文献
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The first Cenozoic avian remains from Venezuela are described. The material comprises an associated right tarsometatarsus and tibiotarsus from the earliest Pliocene of the Codore Formation, northwestern Venezuela. The fossil-bearing horizon represents a deltaic paleoenvironment. The elements are long and narrow, and the presence of a circular incisura intercondylaris bordered proximally by a prominent and centrally-situated tuberculum m. tibialis anticus on the tibiotarsus, allows confident referral to the Ciconiidae (storks). The elements are a close match in morphology and size to the extantJabiru mycteria (Jabiru Stork), although the presence on the distal tibiotarsus of a well-defined caudal sulcus, a narrower sulcus extensorius and shallower angled pons supratendineus, and on the tarsometatarsus of a narrower and deeper sulcus on the plantar surface and a less prominent ridge laterally bordering the fossa supratrochlearis plantaris indicate that this is a new species,Jabiru codorensis n. sp.Jabiru mycteria, the only living species, still occurs in Venezuela, where it is found mostly in grassy wetlands. These specimens represent the first fossil record ofJabiru, as well as the first pre-Pleistocene record of fossil birds from Venezuela. 相似文献