Skip to content. | Skip to navigation

Personal tools

You are here: Home

Search results

RSS Subscribe to an always-updated RSS feed.

3079 items matching your search terms.
Filter the results.
Item type



































New items since



Sort by relevance · date (newest first) · alphabetically
Article Reference Differentiation between two salt marsh beetle ecotypes: Evidence for ongoing speciation
The plausibility of trait divergence under divergent natural selection in the presence of gene flow in natural populations is a contentious issue in evolutionary research. Its importance lies in the fact that this process is thought to be one of the key triggers in ecological speciation in which a species splits into ecologically distinct forms when separate niches are occupied. in this study we demonstrate strong genetic divergence at the IDH1 locus between pond- and canal-inhabiting individuals of the salt marsh beetle Pogonus chalceus from the Guerande salt fields. Moreover, wing size, a trait that has a heritable basis in this species, was significantly larger in the pond populations, which is in concordance with the unstable nature of this habitat. The relationship between IDH1 allele frequencies and wing size variation was consistent with patterns seen across western European populations. By means of neutral allozymes and microsatellites we detected a small but significant degree of sexual isolation between ecotypes. We conclude that speciation is ongoing and that divergence reflects a balance between selection and gene flow.
Located in Library / RBINS Staff Publications
Article Reference Digital elevation model generation for historical landscape analysis based on LiDAR data, a case study in Flanders (Belgium)
Located in Library / No RBINS Staff publications
Article Reference Digital mapping of coastal boulders – High-resolution data acquisition to infer past and recent transport dynamics.
Located in Library / RBINS Staff Publications 2020
Article Reference Digital mapping of coastal boulders – high-resolution data acquisition to infer past and recent transport dynamics
Coastal boulder fields provide clues to long-term frequency-magnitude patterns of coastal flooding events and have the potential to play an important role in coastal hazard assessment. Mapping boulders in the field is time and labour-intensive, and work on intertidal reef platforms, as in the present study, is physically challenging. By addressing coastal scientists not specialized in remote sensing, this contribution reports on the possibilities and limitations of digital applications in boulder mapping in Eastern Samar, Philippines, where recent supertyphoons Haiyan and Hagupit induced high waves, coastal flooding and boulder transport. It is demonstrated how satellite imagery of submetre resolution (Pléiades, WorldView-3) enables efficient analysis of transport vectors and distances of larger boulders, reflecting variation in latitudes of both typhoon tracks and approaching angles of typhoon-generated waves. During the investigated events, boulders with a-axes of up to 8 m were clearly identified to have been shifted for up to 32 m, mostly along the seaward margin of the boulder field. It is, however, hard to keep track of smaller boulders, and the length of a-axes and b-axes including their orientation is often impossible to map with sufficient accuracy. Orthophotographs and digital surface models created through the application of an unmanned aerial vehicle and the ‘Structure from Motion’ technique provide ultrahigh-resolution data, and have the potential to not only improve the results of satellite image analysis, but also from field mapping and may significantly reduce overall time in the field. Orthophotographs permit unequivocal mapping of a- and b-axes including their orientation, while precise values for c-axes can be derived from the respective digital surface models. Volume of boulders is best inferred from boulder-specific Structure from Motion-based three-dimensional models. Battery power, flight speed, and altitude determine the limits of the area covered, while patches shielded by the boulders are difficult to resolve. For some tasks field mapping remains mandatory and cannot be replaced by currently available remote sensing tools: for example, sampling for rock type, density and age dating,recording of lithological separation of boulders from the underlying geological unit and of geomorphic features on a millimetre to decimetre-scale, or documentation of fine-grained sediment transport in between the boulders in supratidal settings. In terms of future events, the digital products presented here will provide a valuable reference to track boulder transport on a centimetre to decimetre-scale and to better understand the hydrodynamics of extreme-wave events on a fringing reef coastline.
Located in Library / RBINS Staff Publications 2019
Article Reference Dinoflagellate cyst biostratigraphy and palaeoecology of the early Paleogene Landana reference section, Cabinda Province, Angola
Forty-four rock samples from the Landana section, belonging to the historical Dartevelle collection of the Royal Museum for Central Africa (RMCA) at Tervuren, Belgium, were palynologically processed and analysed. Systematic analysis of the samples from the Landana sea cliff locality has revealed 90 dinoflagellate cyst taxa spanning an interval that ranges at least from the middle Paleocene to the late Eocene/early Oligocene. This locality represents the first extensive sub-equatorial African Paleogene dinoflagellate cyst record. Dinoflagellate cyst occurrences were calibrated and evaluated against newly revised foraminiferal ranges. This novel dinoflagellate cyst biostratigraphic record was compared and correlated with contemporaneous records relatively close by in the Gulf of Guinea, as well as with records from more distant locations such as Antarctica, Australia and New Zealand. A preliminary dinoflagellate cyst zonation is here proposed comprising three zones and five unzoned yet otherwise distinct intervals. The lower part of the Landana section records a large portion of the early to middle/ late Selandian, which is made apparent by the presence of taxa such as Isabelidinium cingulatum, Isabelidinium? viborgense, and Spinidinium densispinatum. The Thanetian through Lutetian part of the section is more fragmentary and is devoid of any significant marker taxa normally typical for this time interval elsewhere. The upper part of the record is largely devoid of dinoflagellate cysts, with the few dinoflagellate cyst-bearing samples pointing to an Eocene to early Oligocene age. Dinoflagellate cyst assemblages are relatively variable and often largely dominated by a single particular taxon or complex. We record remarkably abundant peridinioid cysts signalling high palaeoproductivity for protracted periods of time, resulting from either heightened terrestrial influence or enhanced upwelling.
Located in Library / RBINS Staff Publications 2018
Article Reference Dinoflagellate cyst events and depositional history of the Paleocene/Eocene boundary interval in the southern North Sea Basin
Located in Library / RBINS Staff Publications
Article Reference Dinosaur egg nests, mammals and other vertebrates from a new Maastrichtian site of the Hateg Basin (Romania)
About ten dinosaur nests of large megaloolithid-type eggs have been discovered in the new Maastrichtian locality of Tote¸sti-baraj (Ha¸teg Basin, Romania). This is the largest dinosaur egg nest site discovered in Romania. Teeth and other micro-remains of vertebrates such as hadrosaurs, ankylosaurs, theropods, lizards and amphibians are associated with the eggs in the sediments, reflecting the great biodiversity of the Ha¸teg Basin during the Maastrichtian. But the most remarkable collected micro-remains are teeth of mammals representing at present the richest multituberculate collection from the Upper Cretaceous of Europe.
Located in Library / RBINS Staff Publications
Article Reference Dipterological survey in Mitaraka Massif (French Guiana) reveals megadiverse dolichopodid fauna with an unprecedented species richness in Paraclius Loew, 1864 (Diptera: Dolichopodidae)
Located in Library / RBINS Staff Publications 2018
Article Reference Direct and indirect effects of metal stress on physiology and life history variation in field populations of a lycosid spider
1. Under stress, life history theory predicts reduced growth rates and adult sizes, reduced reproductive allocation, production of larger offspring and postponed reproduction. Both direct and indirect effects of metals can explain these trends, mainly linked to energetic constraints. Metallothionein-like proteins (MTLP's) are believed to be an important defense mechanism against the adverse effects of metals and other stressors. 2. We tested these predictions comparing six field populations of the wolf spider Pardosa saltans, three of which were on sites that are historically polluted with heavy metals. 3. As expected for life histories evolving under energetic constraints, adult size and condition correlated negatively and egg mass positively with Cd concentrations for a subset of four populations. In the population that showed the highest cadmium and zinc body burdens, reproductive output and allocation were lowest and reproduction was postponed. 4. Contrary to our expectation, for all six study populations MTLP concentrations did not increase in exposed populations, indicating that this defense mechanism cannot explain the observed variation in life histories. 5. We conclude that indirect and synergistic effects of metal pollution may be more important than physiological defense mechanisms in shaping life history traits in field populations. (C) 2011 Elsevier Inc. All rights reserved.
Located in Library / RBINS Staff Publications
Article Reference Discerning geological and geographical sources of Belgian Upper Paleolithic fluorites by Rare Earth Elements and Sr-isotopic geochemistry.
Located in Library / RBINS Staff Publications