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51.
We studied the diets of four sympatric carnivores in the flooding savannas of western Venezuela by analysing predator DNA and prey remains in faeces. DNA was isolated and a portion of the cytochrome b gene of the mitochondrial genome amplified and sequenced from 20 of 34 scats. Species were diagnosed by comparing the resulting sequences to reference sequences generated from the blood of puma (Puma concolor), jaguar (Panthera onca), ocelot (Leopardus pardalus) and crab-eating fox (Cerdocyon thous). Scat size has previously been used to identify predators, but DNA data show that puma and jaguar scats overlap in size, as do those of puma, ocelot and fox. Prey-content analysis suggests minimal prey partitioning between pumas and jaguars. In field testing this technique for large carnivores, two potential limitations emerged: locating intact faecal samples and recovering DNA sequences from samples obtained in the wet season. Nonetheless, this study illustrates the tremendous potential of DNA faecal studies. The presence of domestic dog (Canis familiaris) in one puma scat and of wild pig (Sus scrofa), set as bait, in one jaguar sample exemplifies the forensic possibilities of this noninvasive analysis. In addition to defining the dietary habits of similar size sympatric mammals, DNA identifications from faeces allow wildlife managers to detect the presence of endangered taxa and manage prey for their conservation.  相似文献   
52.
The taxonomic status of the Iriomote cat ( Prionailurus iriomotensis Imaizumi 1967) has been the subject of considerable discussion. Wozencraft's (1993) decision that it is merely a subspecies of Prionailurus bengalensis has been adopted by IUCN, which may affect the chances of conserving this unique animal. This paper reports on an investigation into the relationship between the Iriomote cat and other species, using skull measurements to calculate skull configurations, from which species and subspecies may be compared with each other. The results prove that the Iriomote cat cannot be subsumed as a subspecies of Prionailurus bengalensis but is a species of its own. It is closely related to the genus Prionailurus but also has affinities with the genera Pardofelis and Profelis . It appears to be a very ancient species, a 'missing link', nearer to the common root of the cat tribe than any other extant species.  相似文献   
53.
Abstract

The distribution of the Indian Crested Porcupine Hystrtx indica in Iraq is described, with 19 additional new localities. The population has apparently has been declining during the last twenty years. Preganancy was recorded between April and September, suggesting at least two litters per year. The mean number of embryos was 2.3 per female. 98–100% of the stomach content consisted of plant material.  相似文献   
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During the last two centuries, lynx populations have undergone severe declines and extinctions in Europe. The Alpine lynx, once distributed across the whole Alpine arc, became extinct due to direct human prosecution and deprivation of its main prey in the 1930s. Similar to the Iberian lynx Lynx pardinus , its taxonomy has been subject to several controversies. Moreover, knowing the taxonomic status of the Alpine lynx will help to define conservation units of extant lynx populations in Europe. In this study, we investigated two mitochondrial DNA regions in museum specimens ( n =15) representing the autochthonous Alpine population and in samples from extant Eurasian lynx Lynx lynx populations in Europe and Asia ( n =17). Phylogenetic analysis (cytochrome b , 345 bp) placed the Alpine lynx within the Eurasian lynx lineage. Among all individuals examined, seven different haplotypes (control region, 300 bp) were observed but no unique Alpine haplotype was discovered. Haplotypes of the extinct Alpine population were identical to previously described haplotypes in Scandinavian lynx signifying a recent genetic ancestry with current European populations. Moreover, our genetic data suggest two distinct glacial refugia for the Carpathian and Balkan population. Overall this study demonstrates that historical DNA from extinct populations can help to disentangle the phylogenetic relationships and historical biogeography of taxa with only a limited number of extant populations remaining.  相似文献   
56.
Chemical secretions that are explicitly tied to species recognition may potentially be informative for phylogenetic reconstruction, especially when traditional morphological or molecular characters lack resolution. Anal sac secretions from 16 species within the family Felidae (order Carnivora) were chemically analysed and their utility as phylogenetic characters was assessed. Results were generally consistent across the different chemical data types (e.g. glycolipids, neutral lipids, or phospholipids). Two major clades were indicated, falling out according to body size: one for species greater than 30 kg (Panthera, Uncia, and Puma) and another for those less than 12 kg (remaining species). The primary solutions agreed with respect to the species pairs Prionailurus + Leptailurus, Caracal + Lynx, Oncifelis+Leopardus, Otocolobus+Felis, Panthera leo + P pardus, and P. tigris + Uncia. The only area of disagreement between chemical types was the positioning of the mountain lion (Puma concolor); however, this species appears to cluster with the cheetah (Acinonyx jubatus) in the Tjig cat clade. Although our solutions differ from six previously proposed hypotheses of felid phylogeny (morphological and molecular), the previous estimates all differ strongly amongst themselves reflecting the historical uncertainty regarding felid systematics. Phytogenies derived from the lipid data were very robust and decisive. Few equally most parsimonious trees were obtained, consistency indices were much higher than their expected values, and bootstrap and Bremer support values were also high. Thus, our findings illustrate the species-specific nature of chemical signals and their usefulness as phylogenetic characters.  相似文献   
57.
Patterns of mitochondrial restriction fragment length polymorphism (RFLP) variation were used to resolve more recent relationships among the species of the Felidae ocelot lineage, domestic cat lineage, and pantherine lineage. Twenty-five of 28 restriction enzymes revealed site variation in at least 1 of 21 cat species. The ocelot lineage was resolved into three separate sistertaxa groups: Geoffroy's cat (Oncifelis geoffroyi) and kodkod (O. guigna), ocelot (Leopardus pardalis) and margay (L. wiedii), and pampas cat (Lynchailurus colocolo) and most of the tigrina samples (Leopardus tigrina). Within the domestic cat lineage, domestic cat (Felis catus), European wild cat (F. silvestris), and African wild cat (F. libyca) formed a monophyletic trichotomy, which was joined with sand cat (F. margarita) to a common ancestor. Jungle cat (F. chaus) and black-footed cat (F. nigripes) mtDNAs diverged earlier than those of the other domestic cat lineage species and are less closely related. Within the pantherine lineage, phylogenetic analysis identified two distinct groups, uniting lion (P. leo) with leopard (P. pardus) and tiger (P. tigris) with snow leopard (P. uncia).To whom correspondence should be addressed.  相似文献   
58.
猫科动物的演化关系传统上一直是富有争议的,这很大程度上造成了猫科在属一级的分类众说纷纭。新兴的分子生物学技术为我们理解猫科动物的系统发育提供了新的视角,本文回顾了近些年来的猫科分子系统学研究,以Johnson等(2006)和李钢等(2016)的研究结果为核心,同时结合确切的化石记录进行佐证,推断了猫科的演化历史。我们发现,分子系统学提出的现代猫科动物于晚中新世开始适应辐射、先后分化出了8个支系等观点,与化石证据基本吻合;但是分子系统学对部分支系起源的推断与化石证据存在差异。结合化石记录的分析,我们认为现代猫科8个支系中除狞猫支系和虎猫支系以外,其余均最有可能起源于亚洲,现代猫科动物在演化过程中至少经历了30次洲际迁徙。结合演化历史和形态学研究,我们遵循邱占祥等(2004)的观点,将现存的猫科动物全部归于猫亚科(Felinae),并将现代猫亚科动物划分为15个属40个物种。  相似文献   
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60.
We describe a partial skeleton of Metailurus parvulus from the Turolian site of Kerassia 1 (Northern Euboea, Greece). The material, which consists of a mandible, the anterior and posterior limb-bone elements, some sternal bones and some vertebrae, is the most complete known of this species. The dental material is compared to specimens from Pikermi and Chomateri (Greece), and China. The limb-bones available offer us the possibility to discuss the status of some previously described specimens from Pikermi. The limb proportions indicate that M. parvulus had elongated posterior limbs relative to the anterior ones, which reflects developed jumping skills. M. parvulus had moderately developed cursorial abilities, intermediate between open and closed habitat felids, and probably frequented primarily relatively open woodlands.  相似文献   
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