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1.
Three descendants of Koch, Indo-Mongolid populations, have been studied for their 12 genetic markers of blood group, red cell enzyme and serum protein. Distribution of their phenotype and allele frequencies shows some variants apart from their common alleles. Analysis on genetic material reveals very low differentiation coefficient (GST) value for the total population, and in the distance measure the Poliya and the Tiyor stand close to each other compared to other populations. Data on ethnohistory of the peoples have been discussed in the light of the results obtained from genetic analysis.  相似文献   

2.
Morphological variations of the dental crown and roots provide valuable data for determining the genetic affinities and evolutionary adaptedness of prehistoric human skeletal populations. This paper documents morphological variations of a sample of deciduous teeth from the late Chalcolithic farming village of Inamgaon (1600-700 B.C.) in western India. Hanihara's (1963) grading system of deciduous dental traits was employed in assessing the degree of expression of shovel-shape of incisors, cusp number of upper and lower first molars, hypocone variation, Carabelli's trait, cusp number of lower second molars and the protostylid. Turner's (1970) classification was used to determine presence and size of accessory cusps: entoconulid (C-6) and metaconulid (C-7). Comparative evaluation of the Inamgaon deciduous dental data is hampered by the absence of data for dental features of living and prehistoric South Asian populations. Many of the traits observed in the Inamgaon series exhibit a frequency of occurrence intermediate between figures characteristic of the "Mongoloid" dental complex and the "Caucasoid" dental complex.  相似文献   

3.
Carbon and oxygen isotopic analyses from upper Palaeogene molluscs collected in the Hampshire Basin (S. England) show that, in addition to long‐term trends in the data caused by climatic change, there is variation within samples collected from any one horizon. This variation is not attributable to diagenesis or other “noise”;. Linear trends in data from the meso‐ and oligohaline organisms are salinity‐dependent, as is a differentiation into clusters of the marine and brackish water animals. Within the marine organisms there is further distinction between taxa, controlled by micro‐environment. This is quite distinct from disequilibrium precipitation, as shell growth occurs in equilibrium with local isotopic ratios, though this may not necessarily be the same as contemporary mean ocean values. This “ecological fractionation”; can seriously affect the isotopic signal from a suite of fossils. Its existence should therefore be borne in mind when interpreting any biogenic isotope data from diverse taxa, localities, or micro‐habitats.  相似文献   

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Aim The plant diversity of one location on the Guiana Shield, Kaieteur National Park in Guyana, is used to examine the various hypothesized origins of the flora and to evaluate which may best explain the current plant distributions. Location Kaieteur National Park is located on eastern edge of the Potaro Plateau in central Guyana, South America. The species examined have distributions that vary from local to global. Methods The distribution patterns of the families, genera and species known from Kaieteur are examined using generalized distribution patterns. Results Data on distribution patterns, elevation and habitat were gathered from 131 flowering plant families, 517 genera and 1227 species. These plants represent all taxa that are currently known to occur in the area of the original Kaieteur National Park. Families tend to have cosmopolitan or pantropical distribution, genera are mostly neotropical and at the species level, most species are restricted to the Guiana Shield (c. 40%), northern South America (69%) or neotropical (96%) in distribution, each level inclusive of the previous. Conclusions The flora at the study site in Kaieteur National Park has its strongest affinity with the Guiana Shield; 42.1% of the species have a distribution that corresponds with the Shield or is more restricted within the Shield. There is a distinct flora on the Guiana Shield and its affinities lie with the flora of northern South American and beyond that, the neotropics. The flora is not closely affiliated with the floras of the Brazilian Shield, the Amazon, the Andes, the eastern coastal forests of Brazil, southern South America, or Africa as has been previous suggested.  相似文献   

6.
Western Ghats of Karnataka, an important biodiversity hot spot in the world, rich in insect fauna including termites. Diversity of termites from this region poorly understood. In the present study, we have redescribed 12 species and termites belonging to two families viz., Rhinotermitidae and termitidae based on morphological and molecular differences employing mitochondrial 16s rRNA. Further we have employed Bayesian inference in order to understand phylogenetic relationships among different termite species studied. The integrative taxonomic approach was successful in delimiting the species studied in the present investigation.  相似文献   

7.
The Los Colorados Formation constitutes a continuous continental succession deposited in Western Argentina during the Late Triassic, a time period that is crucial to the record of the faunistic turnover at the Triassic-Jurassic boundary. Many authors have pointed out that its rich tetrapod fauna represents a unique transitional assemblage with elements typical of both Late Triassic and Early Jurassic. However, the possibility that the fauna represented a mixture of Triassic and Jurassic horizons was also proposed. Recently, stratigraphic control of the fossiliferous levels was developed in order to correlate the different localities of the extense Los Colorados outcrops, and a revision of the taxonomic status of most tetrapods recovered is currently undergoing. Preliminary results confirm previous assumptions about the transitional nature of the assemblage where typical Triassic taxa are associated with dinosaur groups known from Early Jurassic levels in other Gondwanan areas. The fossiliferous levels of the upper third of the sequence included several basal archosaurs (aetosaurs, rauisuchids, sphenosuchians), protosuchian crocodiles, dinosaurs (sauropodomorphs, tetanuran theropods), derived therapsids and primitive chelonians. New evidence about tetrapod ichnites of chirotheroid affinities is added to the fossiliferous association.  相似文献   

8.
《Palaeoworld》2015,24(3):293-323
A diverse assemblage of plant macrofossils and the associated representative palynofloral elements are documented from the early Eocene subsurface beds of the Cambay Shale Formation exposed in an open cast lignite mine at Vastan Village in the Surat District, western India. The Vastan mine succession is cyclic, each cycle representing a transgressive burial event terminating in the low energy lagoonal conditions. The higher energy cycle begins with sandy lenses having rich biotic remains, followed by mudstones and molluscan shell beds and ends with lignite seams. The dominantly muddy facies and the associated biota demonstrate predominantly low energy near shore or coastal plain depositional setting with conditions varying from dominantly marine (shallow) through brackish to fresh water. The Vastan mine is a well dated fossil locality with a rich and diverse biota of mammals, birds, snakes, lizards, fish, insects, molluscs, foraminifers, dinoflagellates, and plants. The plants comprise leaf and fruit impressions, seeds, fruits, wood fragments, mangrove rooting structures, fungal thalli and spores, pteridophytic spores, and angiosperm pollen grains. Thirteen macrofossil species, including several morphotaxa, are represented by the families Calophyllaceae, Rutaceae, Anacardiaceae, Rubiaceae, Combretaceae, Lythraceae, Sapindaceae, Malvaceae, and Ebenaceae. The palynological assemblage representing fourteen taxa includes the new species, Notothyrites undulatus, Callimothallus semicircularis, and Carallioipollenites integerrimoides. Habitat and distribution of modern taxa comparable with the fossil assemblage from Vastan suggest a terrestrial lowland environment. The macrofossil taxa are indicative of mesophytic, mixed forest growing under tropical to subtropical climate with sufficient humidity. The occurrence of dipterocarp elements along with taxa such as Swintonia, Pterospermum and Diospyros, etc. seems to suggest the presence of a tropical rain forest in the vicinity of Vastan.  相似文献   

9.
Abstract

Jurassic deposits of shallow to marginal marine (delta) environments are widely reported from different continents of the world. This study shows inter-relationship of the animal-sediment behaviours in shallow and marginal marine conditions, suggesting an interpretation of the possible ichnodisparity. The Jurassic succession exposed at Washtawa Dome and Adhoi Anticline of Wagad highland, Kachchh comprises an approximately 341 m thick succession, divided into two formations – Lower Washtawa and Upper Wagad Sandstone. Eight sparsely to highly bioturbated sedimentary units show twenty-three identifiable ichnospecies from fifteen ichnogenera representing five ichnoassemblages broadly attributable to the Skolithos and the Cruziana ichnofacies, and developed in shallow-marine strandplain shoreface and delta depositional facies. The relative frequency statistical data reveals the dominant occurrence of feeding structures generated by polychaetes preferentially in quartz arenites. These structures represent sub-horizontal, sub-vertical and complex burrows, and show twelve and six categories of architectural designing Callovian-Oxfordian of shallow-marine shoreface and Oxfordian-Kimmeridgian shallow-water delta successions, respectively. The lower ichnodiversity and ichnodisparity associated with the Oxfordian-Kimmeridgian deltaic intervals represents a decrease in the exploitation of under-used ecospace, due to unfavourable environmental conditions rather than an expression of evolutionary radiation.  相似文献   

10.
Cocos sahnii Kaul, a fossil palm fruit, is validated and described from the Fuller's earth deposits of Kapurdi village of Rajasthan considered as Early Eocene in age. The fossil best resembles the genus Cocos, particularly Cocos nucifera L., which is now a common coastal element thriving in highly moist conditions. The recovery of this coconut-like fruit, along with earlier described evergreen taxa from the same formation, suggests the existence of typical tropical, warm and humid coastal conditions during the depositional period. The present arid to semi-arid climatic conditions occurring in Rajasthan indicate drastic climate change in the region during the Cenozoic. The possible time for the onset of aridity in the region which caused the total eradication of semi-evergreen to evergreen forests is discussed, as well as the palaeobiogeography of coconuts.  相似文献   

11.
Cyathophora Michelin, 1843, hitherto well known from the Upper Jurassic and Cretaceous, has been found in the Middle Jurassic (Bajocian) of the Kachchh Basin, western India. Eleven specimens ofCyathophora bourgueti (Defrance, 1826) from the Babia Cliff Sandstone member of the Kaladongar Formation, exposed along the northern scarp of the Kala Dongar, Pachchham Island, Kachchh, are described and illustrated as the earliest Jurassic record of the family CyathophoridaeVaughan & Wells, 1943. It is suggested that the monospecific occurrence ofCyathophora bourgueti was controlled by salinity.   相似文献   

12.
Pollen from modern tree bark samples collected in the Manendragarh Forest Range, Koriya District, Chhattisgarh, India, was investigated with the objective to understand the pollen rain in and around the study area, using modern tree bark samples as a new tool. The palyno-assemblages revealed the dominance of non-arboreals (herbs) over arboreals (trees and shrubs). Trees constitute an average of 17.23% pollen in the total pollen rain, whereas the average contribution of shrubs is only 0.33%. The non-arboreals have an average of 82.44% pollen in the total pollen rain. This bias in the form of representation of trees and shrubs, despite their ample presence in the forest, could be due to the differences in pollen production, dispersal and preservation of taxa, which depends on plant species and climatic conditions.  相似文献   

13.
A small assemblage of macro- and micro floral remains comprising fossil leaf impressions, silicified wood, spores, and pollen grains is reported from the Paleocene–lower Eocene Vagadkhol Formation (=Olpad Formation) exposed around Vagadkhol village in the Bharuch District of Gujarat, western India. The fossil leaves are represented by five genera and six species, namely, Polyalthia palaeosimiarum (Annonaceae), Acronychia siwalica (Rutaceae), Terminalia palaeocatapa and T. panandhroensis (Combretaceae), Lagerstroemia patelii (Lythraceae), and a new species, Gardenia vagadkholia (Rubiaceae). The lone fossil wood has been attributed to a new species, Schleicheroxylon bharuchense (Sapindaceae). The palynological assemblage, consisting of pollen grains and spores, comprises eleven taxa with more or less equal representation of pteridophytes, gymnosperms, and angiosperms. Angiospermous pollen grains include a new species Palmidites magnus. Spores are mostly pteridophytic but some fungal spores were also recovered. All the fossil species have been identified in the extant genera. The present day distribution of modern taxa comparable to the fossil assemblage recorded from the Vagadkhol area mostly indicate terrestrial lowland environment. Low frequency of pollen of two highland temperate taxa (Pinaceae) in the assemblage suggests that they may have been transported from a distant source. The wood and leaf taxa in the fossil assemblage are suggestive of tropical moist or wet forest with some deciduousness during the Paleocene–early Eocene. The presence of many fungal taxa further suggests the prevalence of enough humidity at the time of sedimentation.  相似文献   

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15.
报道和描述了一件平额象左侧M3化石.新材料产自Nangal村附近火山灰层之下的泥岩层,该火山灰是出露于查谟-克什米尔桑巴地区Barakhetar上西瓦立克亚群Nagrota组中年龄为2.48 Ma的火山灰层的延伸.根据齿板数,臼齿长和宽,齿冠长、宽和高,釉质和齿质厚度,齿板长和宽,齿脊频率,冠高指数以及白垩质厚度等齿冠形态参数,暂时将之归为Elephas cf.E.planifrons.新材料的发现将该种的分布上限从2.6 Ma提高到2.48 Ma.  相似文献   

16.
This paper presents the first result of the study on the jumping spiders collected during the India 2002 Expedition held by P. Sipek and M. Fikacek from the Charles University, Prague. Hitherto only 3 species of the genus Curubis were known from Sri Lanka, no females were found (SIMON 1902, ZABKA 1988, PROSZYNSKI 2003). A new species from India, Curubis sipeki sp. nov. (also only in male sex), is described. Bristowia heterospinosa REIMOSER, 1934 is reported for the first time from India.  相似文献   

17.
The palaeoenvironment and age of coal-bearing lacustrine deposits in the Jidong Basin, Heilongjiang Province, is poorly understood. New pollen data from the Yongqing Formation and the overlying lower part of the Daqingshan Formation recovered in borehole 91-205 revealed a rich and diverse palynoflora representing approximately 70 taxa at the genus/family level. Of these taxa, Ulmus, Quercus, Carya, Liquidambar, Pinus, Tilia, Fagus, and Alnus are the main woody elements; these occur together with numerous pteridophytes, subordinate herbs, and rare algae and acritarchs. Abundant woody taxa suggest a mixed deciduous/conifer forest in the region in association with local shrubs, herbs and algal communities. Some of the pollen types, especially those of climate sensitive genera such as Ulmus, Carya, Liquidambar and Fagus, vary considerably in relative abundances, suggesting climate variability. The reflected climate shows an overall trend towards cooling or deterioration which is largely in agreement with global climate change during the Neogene.Comparisons of the pollen record with representative datasets from neighbouring areas, together with the appearance of the highly-evolved genus Artemisia, suggest that the Yongqing Formation and the lower part of the Daqingshan Formation are of Miocene age.  相似文献   

18.
Seventy one fish species belonging to 27 families and 50 genera were collected from various sampling sites spread along the upstream and downstream parts of the Chalakudy river, in the Western Ghats biodiversity hotspot in Kerala, South India. Cyprinids were the most dominant group represented by 24 species belonging to 13 genera, followed by the catfishes of the family Bagridae (7 species from 2 genera) and loaches belonging to the family Balitoridae (5 species from 5 genera). Of the 71 species, 4 belong to the ‘critically endangered’ (CR) and 16 to the ‘endangered’ (EN) category. 3 of the critically endangered species are strictly endemic to the Chalakudy river system. We also collected 5 exotic species several of them categorized as potential pest. Fish species richness (FSR) showed a direct relationship with increasing stream order with maximum values observed in the downstream/low elevation regions. Considerable differences were observed in the FSR between different microhabitats with maximum values observed in bed rock and pool riffle and the lowest in regimes followed by step pools. Diversity and species richness decreased with increasing altitude and higher diversity and species richness were observed in sampling sites located between 0–200 m above sea level. A definite temporal partitioning was also observed with regard to FSR with higher richness during the day time and the lowest observed at dawn. Indiscriminate collection of endemic and threatened ornamental fish species for export, exploitation of endangered food fishes by forest-dwelling communities and local fisher folk, pollution, loss of riparian cover, damming and exotic species threaten the rich ichthyofaunal diversity of Chalakudy River. An urgent need exists for studying the life history traits and demography of the most important endemic and threatened fishes, as lack of information on these aspects have significantly affected conservation efforts. The implementation of strong management strategies like fixing total allowable catch (TAC), and the use of quotas are needed to reduce the overall collection pressure with regard to the trade in native ornamental species from the river.  相似文献   

19.
Hymenopterans Xyelula alexandri Rasnitsyn, sp. nov. (Sepulcidae) and Kotaphialtites frankmortoni Rasnitsyn, gen. et sp. nov. (Ephialtitidae) are described from the Lower or Middle Jurassic Kota Formation, Andhra Pradesh, India. These finds prove a considerable similarity between the Gondwanan and Laurasian hymenopteran faunas during the Jurassic, as well as during the Triassic and Cretaceous.  相似文献   

20.
《Palaeoworld》2015,24(3):324-335
We describe the cricetid rodents represented by Megacricetodon daamsi, Megacricetodon sivalensis, and Myocricetodon sivalensis, recovered from two localities, Dehari and Jhajjar Kotli, lying in the upper part of the Lower Siwalik Subgroup of Jammu Province. The cricetid fauna is similar to that reported from the Pakistan Siwaliks. Based on the species identifications and the stratigraphic range of the cricetid taxa in the Siwalik succession of Pakistan, the age of the Dehari locality is correlated to between 13.8 and 13.2 Ma, whereas an age of 13.8–12.5 Ma would be assigned to the Jhajjar Kotli rodent yielding level. The occurrence of similar rodent taxa at the two investigated sites points to the homotaxial nature of the fossiliferous beds.  相似文献   

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