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81.
Human remains excavated from Vindija cave include a large although fragmentary sample of late Mousterian-associated specimens and a few additional individuals from the overlying early Upper Paleolithic levels. The Mousterian-associated sample is similar to European Neandertals from other regions. Compared with earlier Neandertals from south central Europe, this sample evinces evolutionary trends in the direction of Upper Paleolithic Europeans. Compared with the western European Neandertals, the same trends can be demonstrated, although the magnitude of difference is less, and there is a potential for confusing temporal with regional sources of variation. The early Upper Paleolithic-associated sample cannot be distinguished from the Mousterian-associated hominids. We believe that this site provides support for Hrdli?ka's “Neandertal phase” of human evolution, as it was originally applied in Europe.  相似文献   
82.
Aim We investigated the Quaternary history of the pine processionary moth, Thaumetopoea pityocampa, an oligophagous insect currently expanding its range. We tested the potential role played by mountain ranges during the post‐glacial recolonization of western Europe. Location Western Europe, with a focus on the Pyrenees, Massif Central and western Alps. Methods Maternal genetic structure was investigated using a fragment of the mitochondrial cytochrome c oxidase subunit I (COI) gene. We analysed 412 individuals from 61 locations and performed maximum likelihood and maximum parsimony phylogenetic analyses and hierarchical analysis of molecular variance, and we investigated signs of past expansion. Results A strong phylogeographic pattern was found, with two deeply divergent clades. Surprisingly, these clades were not separated by the Pyrenees but rather were distributed from western to central Iberia and from eastern Iberia to the Italian Peninsula, respectively. This latter group consisted of three shallowly divergent lineages that exhibited strong geographic structure and independent population expansions. The three identified lineages occurred: (1) on both sides of the Pyrenean range, with more genetically diverse populations in the east, (2) from eastern Iberia to western France, with a higher genetic diversity in the south, and (3) from the western Massif Central to Italy. Admixture areas were found at the foot of the Pyrenees and Massif Central. Main conclusions The identified genetic lineages were geographically structured, but surprisingly the unsuitable high‐elevation areas of the main mountainous ranges were not responsible for the spatial separation of genetic groups. Rather than acting as barriers to dispersal, mountains appear to have served as refugia during the Pleistocene glaciations, and current distributions largely reflect expansion from these bottlenecked refugial populations. The western and central Iberian clade did not contribute to the northward post‐glacial recolonization of Europe, yet its northern limit does not correspond to the Pyrenees. The different contributions of the identified refugia to post‐glacial expansion might be explained by differences in host plant species richness. For example, the Pyrenean lineage could have been trapped elevationally by tracking montane pines, while the eastern Iberian lineage could have expanded latitudinally by tracking thermophilic lowland pine species.  相似文献   
83.
Aim This paper evaluates global collection records, evidence of anthropogenic transport methods, and experimental and distributional data relative to temperature requirements to understand the historical and potential dispersal of a well‐known genus of estuarine crab. Location The records analysed are from temperate and tropical coastal ocean areas. Methods The study is based primarily on literature analysis and examination of museum specimens. Results The human‐mediated successful global dispersal of the European shore crabs Carcinus maenas (Linnaeus, 1758) and C. aestuarii (Nardo, 1847) occurred in three major episodes: around 1800, in the 1850s–70s, and in the 1980s–90s. The nineteenth century introductions occurred through transport by ships (probably in hull fouling or in solid ballast), while the introductions in the 1980s could have occurred through a greater variety of dispersal mechanisms (ships’ hull fouling and seawater system fouling; fouling on semisubmersible drilling platforms; ballast water; transport with fisheries products intended for food or bait; scientific research; releases from aquaria maintained for educational or scientific purposes; or intentional non‐governmental releases for human food production). These introductions have resulted in Carcinus’ establishment in five temperate regions outside of its native Europe in Atlantic North America, Australia, South Africa, Japan and Pacific North America, while releases into tropical regions have not established populations. C. maenas’ range in both its native and introduced regions appears to be regulated by similar temperature parameters, enabling an assessment of its potential distribution. Main conclusions The second episode of Carcinus’ global dispersal, the period from the 1850s to 1870s, may be part of a broader surge of world‐wide invasions caused by an increase in shipping.  相似文献   
84.
Aim Interpretation of fossil pollen assemblages may benefit greatly from comparisons with modern palynological and vegetation analogues. To interpret the full‐ and late‐glacial vegetation in eastern‐central Europe we compared fossil pollen assemblages from this region with modern pollen assemblages from various vegetation types in southern Siberia, which presumably include the closest modern analogues of the last‐glacial vegetation of central Europe. Location Czech and Slovak Republics (fossil pollen assemblages); Western Sayan Mountains, southern Siberia (modern pollen assemblages). Methods Eighty‐eight modern pollen spectra were sampled in 14 vegetation types of Siberian forest, tundra and steppe, and compared with the last‐glacial pollen spectra from seven central European localities using principal components analysis. Results Both full‐ and late‐glacial pollen spectra from the valleys of the Western Carpathians (altitudes 350–610 m) are similar to modern pollen spectra from southern Siberian taiga, hemiboreal forest and dwarf‐birch tundra. The full‐glacial and early late‐glacial pollen spectra from lowland river valleys in the Bohemian Massif (altitudes 185–190 m) also indicate the presence of patches of hemiboreal forest or taiga. Other late‐glacial pollen spectra from the Bohemian Massif suggest an open landscape with steppe or tundra or a mosaic of both, possibly with small patches of hemiboreal forest. Main conclusions Our results are consistent with the hypothesis that during the full glacial and late glacial, the mountain valleys of the north‐western Carpathians supported taiga or hemiboreal forest dominated by Larix, Pinus cembra, Pinus sylvestris and Picea, along with some steppic or tundra formations. Forests tended to be increasingly open or patchy towards the west (Moravian lowlands), gradually passing into the generally treeless landscape of Bohemia, with possible woodland patches in locally favourable sites.  相似文献   
85.
86.
The study of planktonic foraminifera from the Lower Cretaceous succession at Angles (Southeastern France) directly correlated with ammonites, confirms that the origin of morphotypes with radially elongated chambers occur earlier than previously recorded. In particular, the species Hedbergella semielongata and Hedbergella roblesae bearing subclavate to clavate chambers first appear in the upper Hauterivian, just predating the onset of the oceanic anoxic Faraoni event. Based on these observations, a new zonation is proposed.  相似文献   
87.
Europe has at present the most extensive network of palynological sites covering the Late Pliocene and the Early Pleistocene or roughly the Gelasian-Calabrian Stages. This paper covers 10 points of recent progress in the palynology of this time period: 1) the contribution of palynology to truly global stratigraphy, 2) the existence and steps of vegetation succession after a glacial period, 3) the causes for the disappearance from Europe of some taxa, 4) the location and the types of vegetation refugia, 5) the causes of the low arboreal pollen representation in glacial times, 6) the extent of extreme glacial conditions, 7) the input of long marine records to short terrestrial ones, 8-9) cyclopalynostratigraphy for wiggle matching dating and duration estimations and, finally, 10) short glacial periods and long interglacial ones in an obliquity-forced climate.  相似文献   
88.
In the Bifrons to Aalensis Ammonite Zones of the Vrines section (Toarcian stratotype), woody phytoclasts, nonsaccate pollen grains, and marine assemblages (dinoflagellate cysts, acritarchs, and foraminiferal linings) dominate the palynofacies. The dinoflagellate cyst assemblage is cosmopolitan with minor Boreal influences, characterized by relatively high quantities of Micrhystridium, Baltisphaeridium, Mendicodinium spinosum, Nannoceratopsis, and the Parvocysta suite, dominating in turn the marine assemblages. Marine assemblage compositions, both dinoflagellate cysts and acritarchs, and calcareous nannofossil abundances are different in marl and limestone lithotypes of the Vrines section. Calcareous nannofossils are generally more abundant in marls than in limestones, they display however a cyclic pattern of semiquantitative abundances in phase with lithological cycles. Although a diagenetic overprint cannot be completely excluded to explain such a difference, it seems likely that these dissimilarities are in part primary, the results of variations in terms of proximality-distality, and climatic fluctuations. A mean duration of 117.6 Kyr per marl-limestone alternation, and the stacking of four marl-limestone alternations for 470.6 Kyr, suggest a control by the Earth's two orbital eccentricity cycles. It is likely that the palaeoenvironmental conditions, which influenced the formation of marl-limestone alternations, also controlled the variations in marine phytoplankton assemblages.  相似文献   
89.
Quantitative surveys of the chrysopid fauna from southwestern Europe, namely the Iberian and Italian peninsulas, France south of 46° N, and the west-Mediterranean Islands, were analysed. A total of 56 species of Chrysopidae were reported, of which three species were abundant. These, Chrysoperla carnea (Stephens, 1836) sensu lato, Dichochrysa prasina (Burmeister, 1839) and D. flavifrons (Brauer, 1850), comprised a large percentage of the specimens. For the rarer species, comments are made on their distributions, the enhanced geographic range of exotic ones, and on levels of endemism and stenotopy.  相似文献   
90.
Species richness of migratory birds is influenced by global climate change   总被引:2,自引:2,他引:0  
Aim  Global climate change is increasingly influencing ecosystems. Long-term effects on the species richness and composition of ecological communities have been predicted using modelling approaches but, so far, hardly demonstrated in the field. Here, we test whether changes in the composition of bird communities have been influenced by recent climate change.
Location  Europe.
Methods  We focus on the proportion of migratory and resident bird species because these groups are expected to respond differently to climatic change. We used the spatial relationship between climatic factors and bird communities in Europe to predict changes in 21 European bird communities under recent climate change.
Results  Observed changes corresponded significantly to predicted changes and could not be explained by the effects of spatial autocorrelation. Alternative factors such as changes in land use were tested in a first approximation as well but no effects were found.
Main conclusions  This study demonstrates that global climate change has already influenced the species richness and composition of European bird communities.  相似文献   
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