Search publications of the members of the Royal Belgian institute of natural Sciences
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Book review of Delange, E. & H. Jaritz — Elephantine XXV. Der Widderfriedhof des Chnumtempels. Mit Beiträgen zur Archäozoologie und zur Materialkunde. Mit einem Beitrag von Françoise Dunand. (Archäologische Veröffentlichungen, 105). Verlag Otto Harrasso
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Piscivory in a Miocene Cetotheriidae of Peru: first record of fossilized stomach content for an extinct baleen-bearing whale
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Les premiers carnivoraformes du Paléocène d’Europe : implications concernant l’origine et la radiation des carnivores (Carnivoramorpha, Mammalia) en Laurasie
- Jusqu’en 2014, le Paléocène d’Europe était caractérisé par l’absence de mammifères carnassiers spécialisés tels que les Carnivoramorpha, ancêtres des Carnivora actuels, des Hyaenodonta et des Oxyaenodonta. Cependant, des fouilles réalisées dans les années 1990 en Roumanie et au milieu des années 2000 en France dans des gisements datant du Paléocène terminal ont permis de découvrir plusieurs fossiles de mammifères carnassiers spécialisés. Les spécimens, que nous avons récemment étudiés, appartiennent tous aux Carnivoraformes (un des deux sousgroupes des Carnivoramorpha). L’espèce la plus complète a été découverte à Rivecourt (Oise, France). Elle est notamment représentée par un dentaire portant plusieurs dents (p4, m1 et m2). Le taxon est nouveau et présente les caractères distinctifs du genre Vassacyon. La seconde espèce provient de la localité de Jibou (Roumanie). Les trois spécimens retrouvés dans ce gisement sont des fragments de dents isolées ; malgré leur usure, des ressemblances avec le genre Gracilocyon sont visibles. Les deux taxons identifiés sont les plus anciennes occurrences pour chacun des genres. Les localités de Rivecourt et de Jibou datant du Paléocène terminal, elles sont considérées comme étant pratiquement contemporaines des gisements américains regroupés au sein du Clarkforkien (North American Land Mammal Age, NALMA). Cet âge est notamment caractérisé par la présence du plus ancien carnivoraforme connu ; la seule espèce identifiée à ce jour appartient au genre Uintacyon. Ce dernier présente des adaptations totalement différentes de celles de Vassacyon et Gracilocyon. Cette diversité des formes laurasiatiques au Paléocène terminal plaide donc pour l’existence d’une radiation des Carnivoraformes dès le Paléocène. En outre, cette diversité paléocène est en accord avec la diversité des formes recensées au tout début de l’Eocène inférieur en Laurasie. La diversité paléocène, ainsi que l’apparition tardive de Carnivoraformes – déjà dérivés – en Amérique du Nord et en Europe suggère que l’origine de ce groupe est à chercher ailleurs que sur ces deux continents. Les Carnivoraformes apparaissant sur ces deux continents vraisemblablement en même temps que les rongeurs (dont l’origine est asiatique), nous proposons une origine asiatique pour ces mammifères carnassiers. Cette hypothèse explique également les apparitions de Carnivoraformes observées au début de l’Eocène inférieur, à la fois en Europe et en Amérique du Nord. Enfin, et de manière générale, l’étude des échanges intralaurasiatiques aux alentours de la transition Paléocène-Eocène est importante afin de comprendre l’apparition et l’évolution des mammifères modernes (carnivores, primates, rongeurs, périssodactyles, artiodactyles).
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Testing for Depéret’s Rule (body size increase) in Mammals using Combined Extinct and Extant Data
- Whether or not evolutionary lineages in general show a tendency to increase in body size has often been discussed. This tendency has been dubbed “Cope’s rule” but because Cope never hypothesized it, we suggest renaming it after Depéret, who formulated it clearly in 1907. Depéret’s rule has traditionally been studied using fossil data, but more recently a number of studies have used present-day species. While several paleontological studies of Cenozoic placental mammals have found support for increasing body size, most studies of extant placentals have failed to detect such a trend. Here we present a method to combine information from present-day species with fossil data in a Bayesian phylogenetic framework. We apply the method to body mass estimates of a large number of extant and extinct mammal species, and find strong support for Depéret’s rule. The tendency for size increase appears to be driven not by evolution towards larger size in established species, but by processes related to the emergence of new species. Our analysis shows that complementary data from extant and extinct species can greatly improve inference of macroevolutionary processes.
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Towards a cumulative collision risk assessment of local and migrating birds in North Sea offshore wind farms.
- Bird collision assessments are generally made at the scale of a single wind farm. While especially in offshore situations such assessments already hold several assumptions, even bigger challenges exist on estimating the cumulative impact of multiple wind farms and the impacts at population level. In this paper, the number of collision victims at Belgian offshore wind farms was estimated with a(theoretical) collision risk model based on technical turbine specifications, bird-related parameters and bird density data of both local seabirds and passerine migrants. Bird density data were gathered by visual censuses and radar registrations. The outcome of the model was extrapolated to future development scenarios in the Belgian part of the North Sea and in the entire North Sea, and then further used for a preliminary assessment of the impact at population level for the species at risk. The results indicate that the cumulative impact of a realistic scenario of 10,000 turbines in the North Sea might have a significant negative effect at population level for lesser and great black-backed gull. We further show that during a single night of intense songbird migration, the number of collision victims among passerine migrants might be in the order of magnitude of several thousands in the entire North Sea. We argue that it is of great importance to further develop methods to quantify the uncertainties and to minimise the assumptions, in order to assure more reliable cumulative impact assessments.
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Country update for Belgium
- Belgium is located in the center of Europe, far from tectonic plate boundaries, volcanoes or other regions of high crustal heat flow. Despite this, over the last 10 years shallow and deep-medium enthalpy geothermal energy has experienced a slow but positive renaissance. Nevertheless, geothermal energy lags behind other renewable energy sources (RES), still making only a small contribution to a rapidly growing renewable energy sector. In this paper we provide an update on the status of the geothermal energy sector in Belgium, with a focus on the developments over the last 5 years. We also discuss the apparent barriers that currently inhibit the industry and the changes that are expected to pave the way for future expansion.
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The Zemst borehole, first record of the EECO in the North Sea Basin and implications for Belgian Ypresian-Lutetian stratigraphy
- Integration of new data in sedimentology, micropalaeontology and organic carbon isotope analysis of upper Ypresian strata in central Belgium (Zemst hole) enables differentiation of a series of biotic events and carbon isotope trends, which are believed to be associated with the 1.5-million-year-long period of global warming, known as the Early Eocene Climatic Optimum (EECO). The relatively low values in δ13Corg (-26.5‰ to -27.1‰) in the interval from the Panisel Sand to the Merelbeke Clay Members (upper NP12-lower NP13) are shown to be coinciding with a fairly high frequency in Apectodinium (>3%, up to 14%) and a Discoaster-bloom (16%-50%, essentially D. kuepperi). This is quite analogous, although less prominent, to what has been observed during the Paleocene- Eocene Thermal Maximum (PETM: Apectodinium abundance of 75% at middle and high latitudes and Discoaster blooms in tropical areas). The abrupt positive shift of up to 1‰ in δ13Corg values at the base of the overlying Pittem Clay Member (mid-NP13, mid-chron C22r), which is coincident with the virtual disappearances of Apectodinium (<0.1%) and Discoaster (<0.5%) seems to mark the end of the EECO in the southern North Sea Basin. The Zemst data allow the identification of the NP12/NP13 boundary, virtually coinciding with chron C23n/C22r boundary, at the depositional break between the Panisel Sand Member and the overlying Kwatrecht Member. The new data also allow to substantially refine the calcareous nannofossil stratigraphy during Biochron NP15 (mid-Lutetian) at middle latitudes. This is corroborated by additional data from Belgium, which furthermore reveal that the primary criterion for identifying the base of the Lutetian (LO of Blackites inflatus), as adopted in the Gorrondatxe GSSP (Spain), cannot be applied in the North Sea Basin s.s. (excluding the Paris Basin) and that there is an urgent need for defining appropriate substitutes for this boundary at these latitudes.
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Characteristics of direct human impacts on the rivers Karun and Dez in lowland south-west Iran and their interactions with earth surface movements
- Two of the primary external factors influencing the variability of major river systems, over river reach scales, are human activities and tectonics. Based on the rivers Karun and Dez in south-west Iran, this paper presents an analysis of the geomorphological responses of these major rivers to ancient human modifications and tectonics. Direct human modifications can be distinguished by both modern constructions and ancient remnants of former constructions that can leave a subtle legacy in a suite of river characteristics. For example, the ruins of major dams are characterised by a legacy of channel widening to 100's up to c. 1000 m within upstream zones that can stretch to channel distances of many kilometres upstream of former dam sites, whilst the legacy of major, ancient, anthropogenic river channel straightening can also be distinguished by very low channel sinuosities over long lengths of the river course. Tectonic movements in the region are mainly associated with young and emerging folds with NW-SE and N-S trends and with a long structural lineament oriented EeW. These earth surface movements can be shown to interact with both modern and ancient human impacts over similar timescales, with the types of modification and earth surface motion being distinguishable. This paper examines the geomorphological evidence and outlines the processes involved in the evolution of these interactions through time. The analysis shows how interactions between earth surface movements and major dams are slight, especially after ancient dam collapse. By contrast, interactions between earth surface movements and major anthropogenic river channel straightening are shown to be a key factor in the persistence of long, near-straight river courses. Additionally, it is suggested that artificial river development, with very limited river channel lateral migration, may promote incision across an active fold at unusually long distances from the fold “core” and may promote markedly increased sinuosity across a structural lineament.
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Animals at ancient Sagalassos. Evidence of the faunal remains
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3D cranium models of fossils of large canids (Canis lupus) from Goyet, Trou des Nutons and Trou Balleux, Belgium
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A 5000-year pollen and plant macrofossil record from the Osogovo Mountain, Southwestern Bulgaria: Vegetation history and human impact
- Abstract Pollen and plant macrofossil analyses were performed on a sequence 105 cm deep obtained from a peat bog (1750 m) that is located above the present timber-line in the Osogovo Mountain, Southwestern Bulgaria. The palaeovegetation reconstruction, supported by a radiocarbon chronology, revealed the vegetation dynamics and human impact during the last 5000 years. The peat bog formed when a coniferous belt of Abies alba and Pinus (Pinus sylvestris, Pinus nigra) covered the high mountain slopes. Charcoal fragments indicate the presence of a broad-leaved tree community composed of Quercus, Corylus, Carpinus, Tilia, Acer and Ulmus at lower altitudes. Stands of Fagus sylvatica in places with higher air and soil humidity, like river valleys and deep ravines, became established. The pollen assemblages after c. 3200 cal. \BP\ record an important change in the forest composition that led to the replacement of the conifers, mostly A. alba, by the invading communities of F. sylvatica. The reasons for this replacement included factors related to both climate change and anthropogenic disturbance. During the last centuries a large-scale degradation of the woodlands in the mountain has occurred. On a regional scale the palaeoecological evidence is compared with information from palynological, archaeological and historical sources in Southwestern Bulgaria.
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Origin of the forest steppe and exceptional grassland diversity in Transylvania (central-eastern Europe)
- Aim The forest steppe of the Transylvanian Plain is a landscape of exceptionally diverse steppe-like and semi-natural grasslands. Is this vegetation a remnant of a once continuous temperate forest extensively cleared by humans, or has the area, since the last glacial, always been a forest steppe? Understanding the processes that drive temperate grassland formation is important because effective management of this biome is critical to the conservation of the European cultural landscape. Location Lake Stiucii, north-western Romania, central-eastern Europe. Methods We analysed multi-proxy variables (pollen, coprophilous fungi, plant macroremains, macrocharcoal) from a 55,000 year discontinuous sequence (c. 55,000–35,000; 13,000–0 cal. yr bp), integrating models of pollen-based vegetation cover, biome reconstruction, global atmospheric simulations and archaeological records. Results Needleleaf woodland occurred during glacial Marine Isotope Stage (MIS) 3, but contracted at the end of this period. Forest coverage of c. 55% (early Holocene) and 65% (mid-Holocene) prevailed through the Holocene, but Bronze Age humans extensively cleared forests after 3700 cal. yr bp. Forest coverage was most widespread between 8600 and 3700 cal. yr bp, whereas grasses, steppe and xerothermic forbs were most extensive between 11,700 and 8600 cal. yr bp and during the last 3700 cal. yr bp. Cerealia pollen indicate the presence of arable agriculture by c. 7000 cal. yr bp. Main conclusions We have provided the first unequivocal evidence for needleleaf woodland during glacial MIS 3 in this region. Extensive forests prevailed prior to 3700 cal. yr bp, challenging the hypothesis that the Transylvanian lowlands were never wooded following the last glaciation. However, these forests were never fully closed either, reflecting dry growing season conditions, recurrent fires and anthropogenic impacts, which have favoured grassland persistence throughout the Holocene. The longevity of natural and semi-natural grasslands in the region may explain their current exceptional biodiversity. This longer-term perspective implies that future climatic warming and associated fire will maintain these grasslands.
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Origin of the forest steppe and exceptional grassland diversity in Transylvania (central-eastern Europe)
- Aim The forest steppe of the Transylvanian Plain is a landscape of exceptionally diverse steppe-like and semi-natural grasslands. Is this vegetation a remnant of a once continuous temperate forest extensively cleared by humans, or has the area, since the last glacial, always been a forest steppe? Understanding the processes that drive temperate grassland formation is important because effective management of this biome is critical to the conservation of the European cultural landscape. Location Lake Stiucii, north-western Romania, central-eastern Europe. Methods We analysed multi-proxy variables (pollen, coprophilous fungi, plant macroremains, macrocharcoal) from a 55,000 year discontinuous sequence (c. 55,000–35,000; 13,000–0 cal. yr bp), integrating models of pollen-based vegetation cover, biome reconstruction, global atmospheric simulations and archaeological records. Results Needleleaf woodland occurred during glacial Marine Isotope Stage (MIS) 3, but contracted at the end of this period. Forest coverage of c. 55% (early Holocene) and 65% (mid-Holocene) prevailed through the Holocene, but Bronze Age humans extensively cleared forests after 3700 cal. yr bp. Forest coverage was most widespread between 8600 and 3700 cal. yr bp, whereas grasses, steppe and xerothermic forbs were most extensive between 11,700 and 8600 cal. yr bp and during the last 3700 cal. yr bp. Cerealia pollen indicate the presence of arable agriculture by c. 7000 cal. yr bp. Main conclusions We have provided the first unequivocal evidence for needleleaf woodland during glacial MIS 3 in this region. Extensive forests prevailed prior to 3700 cal. yr bp, challenging the hypothesis that the Transylvanian lowlands were never wooded following the last glaciation. However, these forests were never fully closed either, reflecting dry growing season conditions, recurrent fires and anthropogenic impacts, which have favoured grassland persistence throughout the Holocene. The longevity of natural and semi-natural grasslands in the region may explain their current exceptional biodiversity. This longer-term perspective implies that future climatic warming and associated fire will maintain these grasslands.
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Pollen analysis of 15th century cesspits from the palace of the dukes of Burgundy in Bruges (Belgium): evidence for the use of honey from the western Mediterranean
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Fischknochen als Indikatoren für Gewässerzustand und menschliche Fischselektion. Eine zusammenfassende Auswertung mittelalterlicher und neuzeitlicher Fischreste aus dem Rheineinzugsgebiet der Schweiz
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Onderzoek van de macrobotanische resten aangetroffen in de Kartuizerstraat (BR111)
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Onderzoek van de macrobotanische resten aangetroffen in de Korte Beenhouwersstraat (BR229)
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Carpologisch onderzoek Arme Klaren (BR 100, US 412)
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Carpologisch onderzoek Schuitenkaai no5 (BR 249)
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A phylogeny of Cichlidogyrus species (Monogenea, Dactylogyridea) clarifies a host switch between fish families and reveals an adaptive component to attachment organ morphology of this parasite genus
- Background: Parasite switches to new host species are of fundamental scientific interest and may be considered an important speciation mechanism. For numerous monogenean fish parasites, infecting different hosts is associated with morphological adaptations, in particular of the attachment organ (haptor). However, haptoral morphology in Cichlidogyrus spp. (Monogenea, Dactylogyridea), parasites of African cichlids, has been mainly linked to phylogenetic rather than to host constraints. Here we determined the position of Cichlidogyrus amieti, a parasite of species of Aphyosemion (Cyprinodontiformes, Nothobranchiidae) in the phylogeny of its congeners in order to infer its origin and assess the morphological changes associated with host-switching events. Methods: The DNA of specimens of C. amieti isolated from Aphyosemion cameronense in Cameroon was sequenced and analyzed together with that of Cichlidogyrus spp. from cichlid hosts. In order to highlight the influence of the lateral transfer of C. amieti on the haptoral sclerotised parts we performed a Principal Component Analysis (PCA) to compare the attachment organ structure of C. amieti to that of congeners infecting cichlids. Results: Cichlidogyrus amieti was found to be nested within a strongly supported clade of species described from Hemichromis spp. (i.e. C. longicirrus and C. dracolemma). This clade is located at a derived position of the tree, suggesting that C. amieti transferred from cichlids to Cyprinodontiformes and not inversely. The morphological similarity between features of their copulatory organs suggested that C. amieti shares a recent ancestor with C. dracolemma. It also indicates that in this case, these organs do not seem subjected to strong divergent selection pressure. On the other hand, there are substantial differences in haptoral morphology between C. amieti and all of its closely related congeners described from Hemichromis spp.. Conclusions: Our study provides new evidence supporting the hypothesis of the adaptive nature of haptor morphology. It demonstrates this adaptive component for the first time within Cichlidogyrus, the attachment organs of which were usually considered to be mainly phylogenetically constrained.
