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991.
《Comptes Rendus Palevol》2014,13(1):27-40
The Cova del Rinoceront is the first site in the Iberian Peninsula where the genus Haploidoceros has been documented. This discovery of abundant remains is also its first recorded occurrence in Europe during the Upper Pleistocene. The new fossil record strengthens claims that this genus was widely distributed during the Pleistocene, occupying a longer time span at least until MIS 5. Cranial and post-cranial skeletal remains ascribed to this species were recovered from the uppermost layers of the Cova del Rinoceront. The diagnostic features that allow these remains to be unequivocally assigned to H. mediterraneus, include their cranial morphology and antler shape, comprising two sickle-shaped beams, curving backwards and laterally, and a long frontal basal tine. This paper highlights the problems of deer systematics and identification given the high degree of fragmentation of the genus, their relatively homogeneous morphology, a virtual absence of reliable characters and the overlap of measurements between species. 相似文献
992.
Papionin monkey fossils are common in the Plio‐Pleistocene aged karst cave deposits northwest of Johannesburg in South Africa. These deposits have yielded important primate and other vertebrate fauna since their discovery in the early part of the 20th century. In this article, we describe new primate cranial and dental specimens from excavations at the site of Cooper's D in the Sterkfontein Valley that date to around 1.5 million years ago. Unlike other localities in southern Africa, most of the new fossils are referred to Theropithecus oswaldi oswaldi, an extinct gramnivorous monkey related to the living gelada. Diagnostic features of T. o. oswaldi crania and teeth include large, thickly enameled molars with tall, columnar cusps, and high molar relief, an upright mandibular ramus, postorbital constriction, and anterior fusion of temporal lines. Also present in the new sample are teeth referred to Papio sp., which show low crowned bunodont molars, and a number of indeterminate papionin teeth and skull fragments. The presence of T. o. oswaldi at Cooper's D extends the list of known localities where the taxon is found, and may indicate the presence of an open, grassland environment in the area during the early Pleistocene. The abundance of theropith fossils at Cooper's suggests that Papio was not consistently the most common papionin in southern Africa over the past three million years. Am J Phys Anthropol 151:613–629, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
993.
Christophe Falguères Jean-Jacques Bahain James L. Bischoff Alfredo Pérez-González Ana Isabel Ortega Andreu Ollé Anita Quiles Bassam Ghaleb Davinia Moreno Jean-Michel Dolo Qingfeng Shao Josep Vallverdú Eudald Carbonell Jose María Bermúdez de Castro Juan Luis Arsuaga 《Journal of human evolution》2013
The Sierra de Atapuerca, northern Spain, is known from many prehistoric and palaeontological sites documenting human prehistory in Europe. Three major sites, Gran Dolina, Galería and Sima del Elefante, range in age from the oldest hominin of Western Europe dated to 1.1 to 1.3 Ma (millions of years ago) at Sima del Elefante to c.a. 0.2 Ma on the top of the Galería archaeological sequence. Recently, a chronology based on luminescence methods (Thermoluminescence [TL] and Infrared Stimulated Luminescence [IRSL]) applied to cave sediments was published for the Gran Dolina and Galería sites. The authors proposed for Galería an age of 450 ka (thousands of years ago) for the units lower GIII and GII, suggesting that the human occupation there is younger than the hominid remains of Sima de los Huesos (>530 ka) around 1 km away. 相似文献
994.
Robin van Velzen Niklas Wahlberg Marc S. M. Sosef Freek T. Bakker 《Biological journal of the Linnean Society. Linnean Society of London》2013,108(3):546-564
Extant clades may differ greatly in their species richness, suggesting differential rates of species diversification. Based on phylogenetic trees, it is possible to identify potential correlates of such differences. Here, we examine species diversification in a clade of 82 tropical African forest butterfly species (Cymothoe), together with its monotypic sister genus Harma. Our aim was to test whether the diversification of the Harma–Cymothoe clade correlates with end‐Miocene global cooling and desiccation, or with Pleistocene habitat range oscillations, both postulated to have led to habitat fragmentation. We first generated a species‐level phylogenetic tree for Harma and Cymothoe, calibrated within an absolute time scale, and then identified temporal and phylogenetic shifts in species diversification. Finally, we assessed correlations between species diversification and reconstructed global temperatures. Results show that, after the divergence of Harma and Cymothoe in the Miocene (15 Mya), net species diversification was low during the first 7 Myr. Coinciding with the onset of diversification of Cymothoe around 7.5 Mya, there was a sharp and significant increase in diversification rate, suggesting a rapid radiation, and correlating with a reconstructed period of global cooling and desiccation in the late Miocene, rather than with Pleistocene oscillations. Our estimated age of 4 Myr for a clade of montane species corresponds well with the uplift of the Eastern Arc Mountains where they occur. We conclude that forest fragmentation caused by changing climate in the late Miocene as well as the Eastern Arc Mountain uplift are both likely to have promoted species diversification in the Harma–Cymothoe clade. Cymothoe colonized Madagascar much later than most other insect lineages and, consequently, had less time available for diversification on the island. We consider the diversification of Cymothoe to be a special case compared with other butterfly clades studied so far, both in terms of its abrupt diversification rate increase and its recent occurrence (7 Myr). It is clear that larval host plant shift(s) cannot explain the difference in diversification between Cymothoe and Harma; however, such a shift(s) may have triggered differential diversification rates within Cymothoe. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, ●● , ●●–●●. 相似文献
995.
《Geobios》2021
The Paleo-Tokyo Bay (Kanto Plateau) that persisted during the transgression periods in the Middle-Late Pleistocene is known for its rich marine fauna that accommodated both the warm and cold water taxa brought by the Kuroshio and Oyashio Currents, respectively. However, little is known on the paleoichthyofauna in this area and the processes shaping the marine ichthyofauna of modern southern Kanto. We used fossil fish otoliths and teeth discovered in the Sha’ana Tuffaceous Sand Member belonging to the Chibanian Miyata Formation, exposed at Sha’ana-dai, Miura City, Kanagawa Prefecture, Japan, to reconstruct the paleoichthyofauna and its associated paleoenvironment and explore the content of fish assemblages during this period. The Sha’ana Tuffaceous Sand Member was composed of upper sandy mud and lower muddy sand horizons at the exposure. A total of 1,675 fish remains were collected from this site, of which 1,389 were assigned to 62 distinct taxa (20 orders, 31 families). The taxonomic composition revealed taxa from various environments, including shallow continental shelf, epi- to meso-pelagic settings, and the majority were from a generally temperate climatic zone. Paleoenvironmental analyses suggested that the fish assemblages were from the continental shelf (approximate depth of 100–200 m) in a temperate sea where both warm Kuroshio and cold Oyashio Currents had an influence on the biota. The analysis also showed that two boreal fishes, namely Clupea pallasii and Theragra chalcogramma, once had a wider distribution that extended to the southwestern areas of the Paleo-Tokyo Bay. This study provides a more complete view of the related paleobiogeography of marine fishes during the Chibanian and is essential for reconstructing the evolutionary processes of the rich ichthyofauna in the southern Kanto. 相似文献
996.
D. A. Downie 《Journal of Biogeography》2004,31(11):1759-1768
Aim The Southwest USA is characterized by fragmented habitat for a range of species in a manner analogous to island systems. This can restrict gene flow among populations and may promote genetic differentiation and the evolution of endemic populations or species among the forested terrestrial islands. The region has experienced cycles of cooling and warming throughout the Pleistocene and the current isolation among populations may date back only c. 11,000 years. Thus, some studies have found genetic structure that predates the current distribution of organisms. The effect of habitat fragmentation on genetic structure was tested using DNA sequences in a highly specialized herbivorous insect, grape phylloxera, Daktulosphaira vitifoliae, that exhibits poor dispersal capacity and natal‐host associated mating that would seem to predispose it to genetic differentiation. Location Southwestern USA. Methods Phylogenetic trees and statistical parsimony networks were estimated from 458 bp of the mitochondrial cytochrome oxidase I gene sampled from 12 populations in Arizona and New Mexico. Results There was no evidence that populations were differentiated at the level of canyon or mountain range but significant structure was found at the larger level of geographic region. The pattern was confounded by the polyphyly of Southwest (SW) grape phylloxera relative to eastern populations and the coexistence of two highly divergent lineages within populations. Main conclusions An early split of grape phylloxera into the SW has resulted in some differentiation between populations in the Transition and Sonoran + Chihuahuan geographic regions. It is hypothesized that this differentiation has been overlaid by a more recent introduction of haplotypes from midwestern USA populations that occur primarily in the Transition region. The importance of sampling broadly is stressed. 相似文献
997.
998.
Alpine biotas are paradigmatic of the countervailing roles of geographical isolation and dispersal during diversification. In temperate regions, repeated distributional shifts driven by Pleistocene climatic oscillations produced both recurrent pulses of population fragmentation and opportunities for gene flow during range expansions. Here, we test whether a model of divergence in isolation vs. with gene flow is more likely in the diversification of flightless alpine grasshoppers of the genus Podisma from the Iberian Peninsula. The answer to this question can also provide key insights about the pace of evolution. Specifically, if the data fit a divergence in isolation model, this suggests rapid evolution of reproductive isolation. Genomic data confirm a Pleistocene origin of the species complex, and multiple analytical approaches revealed limited asymmetric historical hybridization between two taxa. Genomic-based demographic reconstructions, spatial patterns of genetic structure and range shifts inferred from palaeodistribution modelling suggest severe range contraction accompanied by declines in effective population sizes during interglacials (i.e., contemporary populations confined to sky islands are relicts) and expansions during the coldest stages of the Pleistocene in each taxon. Although limited hybridization during secondary contact leads to phylogenetic uncertainty if gene flow is not accommodated when estimating evolutionary relationships, all species exhibit strong genetic cohesiveness. Our study lends support to the notion that the accumulation of incipient differences during periods of isolation were sufficient to lead to lineage persistence, but also that the demographic changes, dispersal constraints and spatial distribution of the sky islands themselves mediated species diversification in temperate alpine biotas. 相似文献
999.
王庄2号地点、吴家外地点和岳沟1号地点位于丹江口库区淅川县。2009年4月,中国科学院古脊椎动物与古人类研究所对这3处遗址进行了抢救性考古发掘,每个地点发掘面积100 m2,获得石制品数量分别为13件、33件、13件,包括石核、石片、断块、工具等多种类型。3个地点的原料均属就地取材,与各自所在区域的砾石原料构成有关,从原料选择上能看出古人类的有针对性选择。石器分析显示,3处地点的剥片技术均为硬锤直接锤击法,王庄2号地点和吴家外地点的石器大小、质量、石器面貌与南方砾石工业更接近,而岳沟1号地点则与北方石片石器技术面貌相似,表现出中国南北方主工业类型过渡的特点,为研究晚更新世古人类在汉水流域的适应生存、开发过程提供了一批资料。 相似文献
1000.
安徽东至华龙洞因发现距今约30万年的古人类头骨化石和大量动物化石及石制品受到学术界广泛关注。本文对华龙洞遗址的地质、地貌、沉积物特点及洞穴演化过程与古人类活动的关系进行分析。华龙洞地处扬子陆块区西北缘,周边呈现低山—丘陵—湖泊平原地貌景观。与华龙洞遗址密切关联的岩溶洞穴,发育在上寒武统微晶灰岩和白云质灰岩岩系内,中更新以来的地壳运动和岩溶发育是其形成的主要营力。华龙洞遗址是一处坍塌的洞穴,其发育大致经历发育初期(中更新世早期甚至更早)—稳定发育期(中更新世中期)—坍塌埋藏期(中更新世中晚期)等三个阶段,岩溶发育和洞外溪谷的侵蚀使得原始洞穴和堆积物一起在重力作用下坍塌。洞穴坍塌沉积物主要包括围岩岩块与碎屑、各种岩溶沉积物和文化遗物,胶结坚硬,不规则地埋藏于裂隙和巨石之间。古人类在遗址的活动时间处在距今约30万年前的稳定发育期,石制品和骨骼表面痕迹证据表明,华龙洞古人类具备依据不同原料的特点采取砸击法与锤击法并用的技术策略;石片边缘的使用痕迹和动物骨骼表面痕迹显示,古人类在遗址可能进行过肢解动物的行为。本研究对揭示长江下游中更新世中晚期古人类演化与适应生存行为具有重要意义。 相似文献