Search

Middle Eocene interbasaltic deposits of Hareø, West Greenland, have yielded a rich leaf and fruit record, which was described in the second half of the nineteenth century. In this study, we describe dispersed spores and pollen from the Aumarûtigssâ Member of the Hareøen Formation in order to obtain a more comprehensive picture of the late middle Eocene vegetation of West Greenland. The spore/pollen assemblage, derived from a resinite-rich coal bed, comprises 123 taxa, of which 14 belong to mosses, ferns and fern-allies, 14 to gymnosperms, and 95 to angiosperms. The most diverse groups of angiosperms are Fagales, comprising 27 taxa, and Rosales, represented by nine taxa. Along with conifers belonging to Pinaceae, these groups reflect the temperate character of the Hareø flora. In addition, a few 'exotic' elements include cycads probably belonging to an extinct temperate lineage that was widespread across the Northern Hemisphere during the Paleogene, palm trees, members of Mastixioideae and Santalaceae, both of which were characteristic elements of more southern warm temperate floras of Europe. A detailed comparison with macrofossil and spore/pollen assemblages of roughly coeval sites from Axel Heiberg Island (Canada), Spitsbergen (Arctic Ocean), and ODP site 151-913B in the Norwegian-Greenland Sea, show a highly consistent picture of the vegetation during this time. [ABSTRACT FROM AUTHOR]

Late Oligocene leaf assemblages from four sites in Southwestern Siberia (Kurgan, Tyumen, Omsk oblasts) are described. Twenty-three leaf taxa and 3 reproductive structures represent local vegetation of a lake (Salvinia, Typha, Phragmites, Nelumbo, Hemitrapa, Liquidambar, Pterocarya, Alnus, Populus, Salix, Nyssa). Additionally, 57 spore and pollen taxa were recorded from one site (Shish River). Gymnosperms dominate the assemblage with ~30% Pinaceae and ~25% taxodiaceous (papillate) Cupressaceae pollen. Ferns and peat mosses (Sphagnaceae) comprised ~6%. Angiosperms were dominated by Fagaceae, Betulaceae, Juglandaceae and Ulmus and comprised a few exotic elements (Liquidambar, Eucommia, Nyssa, Symplocos); scarce herbaceous plants reflect lakeshore vegetation. The flora of the Turgay type comprised old elements (Nelumbo protospeciosa, Liquidambar europaea, taxodiaceous/papillate Cupressaceae, Quercus sect. Protobalanus) and taxa present in Siberia/Kazakhstan during the Paleogene with later arrivals in Europe (Ulmus pyramidalis, Quercus pseudocastanea, Alnus julianiformis, Byttneriophyllum tiliifolium). A few taxa were endemic in the late Oligocene of western Siberia (Trapa praeconocarpa, Platycrater iljinskajae sp. nov.). Combined macrofossil and palynological evidence places the Shish River site flora into the late Oligocene Zhuravka (Turtas) Formation. Floras of similar composition from western Eurasia are commonly middle Miocene or younger in age highlighting the dynamic spatiotemporal evolution of temperate Eurasian floras during the Cenozoic. [ABSTRACT FROM AUTHOR]

Diospyros is a large genus of woody flowering plants with a predominantly subtropical and tropical modern distribution. Fossils attributed to Diospyros are mainly leaf impressions from Cretaceous and Cenozoic strata across the Northern Hemisphere. However, it is difficult to assign such fossils to Diospyros because genus-diagnostic leaf characteristics remain to be identified. Unequivocal fossil records of Diospyros are few, including staminate flowers with in situ pollen from the late Eocene of South Australia and dispersed pollen from Cenozoic strata in the Northern Hemisphere. Here, we investigated dispersed pollen and calyx remains from Miocene deposits of Denmark using a combined scanning electron/light microscopy approach. Tricolporate, relatively large pollen with lalongate pori and long bow-shaped colpi and a distinctive micro/nanorugulate exine ornamentation together with persistent 4-lobed flower calyces allow unambiguous identification of the genus. Based on the large size of the calyx, we describe a new fossil-species of Diospyros. Further, a review of the fossil pollen record of Diospyros shows that, in addition to the Australian record, the genus was present in South China, western North America and Europe during the Eocene and in East and South Africa and Central Asia during the Oligo-Miocene. Although still scanty, the pollen record can contribute vital information for time-calibrated molecular phylogenies to resolve conflicting biogeographic inferences. A thorough description of the historical biogeography of Diospyros is still in its infancy. While we initiate such a study here, development of a comprehensive picture will require further studies of dispersed pollen grains with high taxonomic resolution. [ABSTRACT FROM AUTHOR]

The piggyback basin of Bezhan, southeastern Albania, was formed during the late Neogene and contains Pliocene/Pleistocene deposits. These continental deposits consist of marls, siltstones and clays separated by a thin series of lignite-seams alternating with clays (Bezhan formation). We investigated leaf fossils and dispersed pollen from marls of the upper portion of this formation. Fifty-two plant taxa comprising algae, gymnosperms, and angiosperms were recovered. Of these, at least 19% belong to extant species and less than 16% belong to taxa today extinct in western Eurasia. Tsuga is represented by three pollen taxa with affinities to modern Chinese, Japanese, and North American species. Herbaceous taxa indicative of steppe (Artemisia, Amaranthaceae) occur in low quantities (≤1%) suggesting an interglacial setting. Four vegetation units are recognised: Wet riparian and aquatic vegetation, mesic oak forest, dry sub-Mediterranean woodland, and montane conifer forest. A comparison of the Bezhan flora with well-dated Pliocene and Pleistocene floras of Italy suggests a Calabrian (late early Pleistocene) age for the upper unit. This estimate is based on the abundance of extant taxa, the absence of subtropical taxa, and threshold values of particular taxa (Tsuga, Carya). The findings are in agreement with age estimates for extant tree species from molecular studies. [ABSTRACT FROM AUTHOR]

The former family Taxodiaceae is currently treated as nine genera in five subfamilies of the family Cupressaceae. Pollen of the 'taxodiaceous' Cupressaceae typically has a papilla in the leptoma area and is common in Cenozoic strata because some of its genera were key elements in lignite forming swamp forests. Dispersed fossil pollen of this group are often assigned to particular genera and, based on the modern ecologies of these taxa, to particular palaeoenvironments. In this study, we investigated pollen of all nine genera of the former Taxodiaceae using light and scanning electron microscopy to evaluate whether pollen morphology can be used to discriminate modern genera of this paraphyletic group. We found few genus- or subfamily-diagnostic characters among members of taxodiaceous Cupressaceae. Features such as orbiculae and pollen and leptoma size cannot be used to discriminate subfamilies. However, three basal subfamilies share short papillae, whereas in two more derived clades (Sequoioideae and Taxodioideae) papillae are markedly longer. In the generally non-papillate core Cupressaceae, the leptoma (aperture) area may or may not possess a distinct circular thinning as also found in the basal grade of taxodiaceous Cupressaceae. Our results show that it is difficult if not impossible to distinguish genera of the ecologically distinct Taxodioideae and Sequoioideae based on pollen morphology. In view of a much wider ecological amplitude of many taxodiaceous Cupressaceae during large parts of the Cenozoic, we conclude that it is not recommendable to infer particular palaeoenvironments on the basis of dispersed taxodiaceous pollen grains alone. [ABSTRACT FROM AUTHOR]

The role of secularization remains underdeveloped in theoretical studies of democratization. We hold that the relation between the two processes is difficult to analyse by help of standard, cross-sectional analysis. We therefore propose a process-oriented model of democratization in relation to secularization. We suggest that these processes do not unfold in random patterns. Theoretically they follow one of four distinct paths: democratization may precede secularization, secularization may precede democratization, democratization may occur without secularization, and democratization and secularization may occur as parallel processes. The contrasts between our model and cross-sectional analysis become particularly obvious when the first and the fourth paths are considered in historical perspective: secularism (as an independent variable) is in both cases positively correlated with democracy (the dependent variable), even though these processes are reversed temporally (path one), or even occur simultaneously (path four). The model therefore demonstrates the need for further research on the relation between democratization and secularization. This includes the problem of why certain states tend to follow certain paths; whether countries may shift between paths; the problem of democratic consolidation; the role of state-formation to secularization and democratization; and the contextual dependence of the model, including the relation between institutions and values/behaviour. [ABSTRACT FROM PUBLISHER]

The uppermost Eocene Florissant Formation, Rocky Mountains, Colorado, has yielded numerous insect, vertebrate and plant fossils. Three previous comprehensive palynological studies investigated sections of lacustrine deposits of the Florissant Formation and documented the response of plant communities to volcanic eruptive phases but overall found little change in plant composition throughout the investigated sections. These studies reported up to 150 pollen and spore phenotypes. In the present paper, we used a taxonomic approach to the investigation of dispersed pollen and spores of the Florissant Formation. Sediment samples from the shale units containing macrofossils were investigated using light microscopy (LM) and scanning electron microscopy (SEM). The general picture of the palynoflora is in agreement with previous studies. However, the combined LM and SEM investigation provides important complementary information to previous LM studies. While a fairly large amount of previous pollen determinations could be confirmed, the purported taxonomic affinities of several pollen phenotypes need to be revised. For example, pollen referred to asPodocarpusorPodocarpiditessp. belongs to the PinaceaeCathaya, Malus/Pyrusactually belongs to Dryadoideae, pollen of the form genusBoehlensipollisreferred to as Proteaceae/Sapindaceae/Elaeagnaceae orCardiospermumbelongs to Sapindaceae but not toCardiospermum, and pollen ofPersicarioipollissp. B with previously assumed affinities to Polygonaceae actually belongs to Thymelaeaceae.Pandaniiditesand one type ofMalvacipolliscannot be linked with Pandanaceae and Malvaceae. A few taxa are new records for Florissant (Ebenaceae:Diospyros; Mernispermaceae; Trochodendraceae:Tetracentron). In general, SEM investigations complement the LM palynological studies and improve the identification of dispersed pollen and spores and enable integration of data from dispersed fossil pollen into a wide range of comparative morphological, taxonomic, evolutionary, biogeographic and phylogenetic studies. [ABSTRACT FROM AUTHOR]

It has been suggested that pollen ornamentation can be used to distinguish infrageneric groups inQuercus. Here, we document pollen morphology of nearly all species ofQuercusGroup Ilex and show that they share distinctive microrugulate pollen ornamentation. Furthermore, pollen ultrastructure of all six infrageneric groups ofQuercuswas studied comparatively and evaluated using a phylogenetic framework for Fagaceae. Characteristics of the foot layer, such as its thickness and continuity, and the ratio foot layer to tectum are not stable within infrageneric groups ofQuercus. The foot layer in derived groups (Groups Cerris, Quercus, Lobatae) is irregular, discontinuous and thin (type 2 foot layer). Members of Groups Cyclobalanopsis and Ilex either have a regular, continuous, and comparatively thick foot layer (type 1), or a type 2 foot layer. Only Group Protobalanus consistently has a type 1 foot layer and is similar toTrigonobalanusandColombobalanusamong trigonobalanoids, and to castanoids. Because (I) all except for one species ofCastaneaandNothofagushave a type 1 foot layer and (II) basal groups inQuercusmay have a type 1 foot layer, we suggest that this is the ancestral state in Fagaceae, and that the type 2 foot layer ofFagusis derived. [ABSTRACT FROM AUTHOR]

This article takes as a point of departure a well-known but rarely tested assumption in the literature on state-building and democratisation, namely that democratic regimes in newly established states are politically unstable. When states take their first steps as independent entities, the state-building process is often incomplete, the political institutions fragile and democratic routines yet to be established. However, with increasing years of independence, these democratic shortcomings are expected to be remedied. This makes it reasonable to assume that the likelihood of democratic failure decreases with increasing years as an independent state. Based on an extensive empirical data set, the conclusion was reached that there is indeed a negative relationship between the length of independence and democratic failure and that this association is insensitive to the period in time when the countries received their independence. Furthermore, the results suggest that the length of democratic rule has a positive impact on democratic stability. However, this pattern is detectable only in states created after 1946. [ABSTRACT FROM AUTHOR]

Does size of municipality have an impact on political support? This study investigates the connection between municipality size and political support in 55 Swedish municipalities. Three hypotheses about the connection between municipality size and political support are developed from previous research. These hypotheses claim negative, positive, and no connection between municipality size and political support. In the empirical analysis, two aspects of size (area and population) and eleven aspects of political support (five aspects of political trust, participation in parliamentary and municipal elections, political interests, party identification, and activity in associations) are included. The analysis also includes six aspects of municipality composition (age, education, ethnicity, income, labour market activity and urbanisation). When the three hypotheses are empirically tested, the analysis indicates that several aspects of political support have negative correlations with area size, while only one of the aspects has a negative correlation with population size. However, a major part of the investigated aspects has no connection with municipality size and the connections that are indicated by the analysis are only moderate in their strength. [ABSTRACT FROM AUTHOR]

This article presents a new methodology for multilevel analysis using a small number of cases, named Comparative Multilevel Analysis (CMA). A classic problem in comparative studies has been the presence of too many variables and too few cases. One traditional solution to this problem has been to study subsystems within a system. However, the approach has fundamental limitations: it cannot analyse subsystems from different contexts, nor can it determine how conditions on the system level influence subsystems. By proposing four additions to traditional methodology, this article offers a new method of comparing subsystems from different contexts in order to analyse the effect of context on subsystems. The author also illustrates how CMA can be combined with Qualitative Comparative Analysis and Fuzzy-set, thereby enabling these methods to be used in the study of subsystem and context effects. [ABSTRACT FROM AUTHOR]

Research on citizen participation has been guided by two core issues: first, the observation of a widening repertory of modes of participation, and second, the argument that participation is not an undifferentiated phenomenon, but must be conceived as an inherently multidimensional reality. In this article, we argue that conventional participation research has focused too one-sidedly on quantitatively expanding the range of types of activities, while the complex dimensionality is not reflected in the measures used. We formulate a methodological critique by using the metaphor of the 'black box', which refers to the implicit and unquestioned assumption that distinct types of activities and associations represent homogeneous and consistent realities that do not warrant further analytical decomposition. Surveys of participation allocate individuals to different 'participation boxes' by means of a binary logic, leaving a void of what is actually happening inside the boxes. To conclude, we reflect upon the fundamental dilemmas the black box of participation raises for theory and research, and offer conceptual and methodological keys to unlock the participation box. [ABSTRACT FROM AUTHOR]

The starting point for this article is the need for empirical knowledge about organizational configuration for societal risk and safety management activities in a modern welfare society. In this paper, we use Sweden as an empirical frame to analyze the administrative management structure at the local governmental level. The analysis is based on statistical analysis of information from a web-survey with administrative chief/head officials (n = 1283) with responsibilities for different municipal functions and sectors. The sample represented 25% of the Swedish municipalities (n = 290) and the response rate was approximately 60% (n = 766). The responses to two sets of questions (25 and 45 questions) are used for statistical analyses of management structures and task distribution within the municipal organizations. Principal component factor analyses with Varimax and Kaiser's Normalization was applied as a structure detection method. The results indicate a clear and uniform way to institutionalize societal risk and safety management at the local level. Furthermore, the management course of action is found to have different types of value characters. The implications that arise from the patterns identified in this study are considered to be of general relevance and topicality for research and practice in this area. [ABSTRACT FROM AUTHOR]

Dispersed pollen, fruits, and leaves of Tetracentron (Trochodendraceae) are described from the Miocene of Iceland and assigned to a new species, Tetracentron atlanticum. The Icelandic fossils represent the first unambiguous record of Tetracentron for the Cainozoic of Europe. Well-preserved dispersed grains of Tetracentron are also identified from the Eocene and Miocene of western North America and compared to the Icelandic fossils. In general, Tetracentron pollen is rather uniform through the Eocene to Recent, only displaying minor variation in ornamentation. Leaves are diagnostic at the species level. The findings add substantial new information to the generally poor fossil record of Tetracentron and indicate a more circumpolar distribution of the genus than previously assumed. The north-eastern Asian - western North American Cainozoic distribution for plant taxa presently confined to East Asia is relatively common. In contrast, the extension to Iceland is remarkable, particularly in view of the absence of the genus in the fossil record from eastern North America, Greenland, and Central Asia and mainland Europe. [ABSTRACT FROM AUTHOR]

Pollen of Platanus was studied using light (LM) and electron microscopy (SEM and TEM). Overall, pollen is uniform in modern Platanus (small, tricolpate, prolate to spheroidal, reticulate, semitectate). A number of characters, however, display remarkable variability within a taxon and even a single anther (size; foveo‐reticulate, fine to coarse reticulate ornamentation). Platanus kerrii (subgenus Castaneophyllum ) differs from the remaining species by its high and “folded” reticulum and possibly the smooth colpus membrane. Moreover, to our knowledge, pollen of the P. kerrii – type is not known from the fossil record. The exine in modern and fossil Platanaceae shows great structural similarity, but the thickness of the foot layer within the ectexine is less variable and normally smaller in modern taxa. Furthermore, in Early Cretaceous to Early Cainozoic Platanaceae a number of distinct pollen types occurred that are not known within the modern Platanus . Considering pollen of Platanaceae from the Early Cretaceous to today, a dynamic picture of the evolution of the family emerges. In the first phase (Early Cretaceous) pollen of extinct genera such as Aquia differed considerably from modern Platanus and shows strong similarity to basal eudicot taxa such as Ranunculales (e.g. Lardizabalaceae). The Late Cretaceous Platananthus hueberi displays a distinct coarse reticulum that is unknown from modern Platanus but similar to some taxa of Hamamelidaceae (e.g. Exbucklandia ). After the first phase of eudicot radiation that appears to have been characterized by strongly reticulate evolution, platanaceous diversity decreased in the course of the Cainozoic. Despite this, the pollen type of the modern subgenus Castaneophyllum ( P. kerrii type) seems to be an innovation that originated after the initial radiation of the family. [ABSTRACT FROM AUTHOR]