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Article Reference Significant loss of mitochondrial diversity within the last century due to extinction of peripheral populations in eastern gorillas
Species and populations are disappearing at an alarming rate as a direct result of human activities. Loss of genetic diversity associated with population decline directly impacts species’ long-term survival. Therefore, preserving genetic diversity is of considerable conservation importance. However, to assist in conservation efforts, it is important to understand how genetic diversity is spatially distributed and how it changes due to anthropogenic pressures. In this study, we use historical museum and modern faecal samples of two critically endangered eastern gorilla taxa, Grauer’s (Gorilla beringei graueri) and mountain gorillas (Gorilla beringei beringei), to directly infer temporal changes in genetic diversity within the last century. Using over 100 complete mitochondrial genomes, we observe a significant decline in haplotype and nucleotide diversity in Grauer’s gorillas. By including historical samples from now extinct populations we show that this decline can be attributed to the loss of peripheral populations rather than a decrease in genetic diversity within the core range of the species. By directly quantifying genetic changes in the recent past, our study shows that human activities have severely impacted eastern gorilla genetic diversity within only four to five generations. This rapid loss calls for dedicated conservation actions, which should include preservation of the remaining peripheral populations.
Located in Library / RBINS Staff Publications 2018
Article Reference Silpha tyrolensis Laicharting, 1781 (Coleoptera: Silphidae), an unexpected addition to the Belgian fauna
In the course of the Belgian Silphidae Project, four specimens of Silpha tyrolensis Laicharting, 1781 were encountered when studying the unidentified Silphidae in the entomological collection of the Haute École Provinciale de Hainaut-Condorcet in Ath. These are the first records of this species for Belgium and are from the period 1990–2010. Subsequent recent trapping in the region where the specimens were found revealed no additional specimens. In this paper the records are presented and the distribution of the species in Belgium and Europe is mapped and discussed.
Located in Library / RBINS Staff Publications 2020
Inproceedings Reference Simulation of boulder transport in a flume comparing cuboid and complex-shaped boulder models
Coasts around the world are affected by high-energy wave events like storm surges or tsunamis depending on their regional climatological and geological settings. Coarse clasts (boulders to fine blocks) deposited on the shore can provide evidence for hazard-prone areas and physical characteristics of the flooding event. In order to better understand the process of boulder transport by tsunamis and to calibrate numerical hydrodynamic models, we conducted physical boulder transport experiments in a Froude-Scale of 1:50 utilizing idealized boulder shapes (cuboids) as well as realistic, complex boulder shapes based on real-world data. Comparing the behaviour of natural shaped with idealized boulders, allows identifying how the boulder shape influences the transport process in terms of transport mode (sliding, shifting, saltation), path and distance. Experiments are conducted in a 33 m long and 1 m wide flat wave flume ending on an ascending coastal profile. The gradient angle of the ramp changes from 11◦ to 4◦ ending on a flat elevated platform resulting in a total length of 4.5 m. The complex shaped boulder model (17.4x9.6x7.6 cm3) is constructed from photogrammetric data of a coastal boulder on Bonaire in the Dutch Caribbean (BOL2 in Engel and May, 2012), which is assumed to be transported by a tsunami. A cuboid boulder model of equivalent volume and weight (14x8x6 cm3) is created for comparison. The tsunami is modelled as a broken bore generated by two computer-controlled pumps. Each experimental run set-up was repeated for at least three times. The results show a significant influence of the boulder shape, in particular regarding the area of the contact surface when the bore approaches the boulder. With increasing contact surface higher transport distances occur. Due to the shape of the complex boulder tends slightly towards a rough ovoid, which is more streamlined than the idealized shape, the effectively acting drag force decreases and leads to reduced transport distances. The predominant transport mode during the experiments was sliding combined with gentle rotating around the vertical axis. However, in several experimental cases the complex boulder significantly rotates while the idealized does not. Recognizing that the transport distance, presumably due to decreasing ground contact and therefore less friction, increases during rotational transport, it is remarkable that the complex boulder still does not reach the transport distances of the idealized one. Experiments for boulder-boulder interactions generally show reduced transport distances. The bore-facing boulder generates a “flow shield” preserving the latter boulder from movement. In consequence, the bore-facing boulder hits its neighbour and stops moving. Within the range of our experiments, this boulder-boulder impact does not exceed a necessary energy-threshold for dislocating the second boulder. Beside further results regarding the influence of the initial water level, increased bottom friction and exper- iment sensitivity, insights into a numerical model based on these experiments will be presented. Engel, M.; May, S.M.: Bonaire’s boulder fields revisited: evidence for Holocene tsunami impact on the Leeward, Antilles. Quaternary Science Reviews 54, 126–141, 2012.
Located in Library / RBINS Staff Publications 2018
Article Reference Six new species of Elpidium Müller, 1880 (Podocopida: Limnocytheridae) from Eastern Brazil
Elpidium is the most common ostracod genus occurring in phytotelmata in the Neotropical region, with distributions ranging from Florida, USA in the north to Rio Grande do Sul, Brazil in the south. However, the genus remains poorly known both in terms of diversity and of the distributional pattern of its species. Here, we describe six new species of Elpidium, E. oxumaen. sp., E. cordiforme n. sp., E. picinguabaensen. sp., E. eriocaularumn. sp., E. higutiaen. sp., E. puriumn. sp., all from phytotelm environments in the Brazilian Atlantic rain forest. In addition, we discuss the distributional pattern and endemicity levels of Elpidium species in the light of these new taxonomic results and argue about possible misunderstandings on the distribution of the type species E. bromeliarum.
Located in Library / RBINS Staff Publications 2023
Article Reference Sixteen issid planthopper species in one day in Dong Son-Ky Thuong Nature Reserve in North Vietnam: Eight new species, one new genus and additional new records (Hemiptera: Fulgoromorpha: Issidae)
Located in Library / RBINS Staff Publications 2023
Article Reference Skull ecomorphological variation of narwhals (Monodon monoceros, Linnaeus 1758) and belugas (Delphinapterus leucas, Pallas 1776) reveals phenotype of their hybrids
Located in Library / RBINS Staff Publications 2022
Article Reference Social status as reflected in the food refuse from late medieval sites in Namur (Belgium)
Located in Library / RBINS Staff Publications
Article Reference Sogana cysana sp. nov., a new tropiduchid planthopper from Chu Yang Sin National Park in Vietnam and key to Vietnamese species of the genus (Hemiptera: Fulgoromorpha: Tropiduchidae)
Located in Library / RBINS Staff Publications 2020
Inproceedings Reference Soil Settlement and Uplift Damage to Architectural Heritage Structures in Belgium: Country-Scale Results from an InSAR-Based Analysis
Soil movement may be induced by a wide variety of natural and anthropogenic causes, which are detectable in the local scale, but may influence the movement of the soil over vast geographical expanses. Space borne interferometric synthetic aperture radar (InSAR) measurements of ground movement provide a method for the remote sensing of soil settlement and uplift over wide geographic areas. Based on this settlement and uplift evaluation, the assessment of the potential damage to architectural heritage structures is possible. In this paper an interdisciplinary monitoring and analysis method is presented that processes satellite, cadastral, patrimonial and building geometry data, used for the calculation of settlement and uplift damage to architectural heritage structures in Belgium. It uses processed InSAR data for the determination of the soil movement profile around each case study, of which the typology is determined from patrimonial information databases and the geometry is calculated from digital elevation models. The impact on the historic structures is calculated from the determined soil movement profile based on various soil-structure interaction models for buildings. The resulting damage is presented in terms of a numerical index illustrating its severity according to different criteria. In this way the potential soil movement damage is quantified in a large number of buildings in an easily interpretable and user-friendly fashion. The processing of InSAR data collected over the previous 3 decades allows the determination of the progress of settlement- and uplift-induced damage in this time period. With the integration of newly acquired and more accurate data, the methodology will continue to produce results in the coming years, both for the evaluation of soil settlement and uplift in Belgium as for introducing related damage risk data for existing architectural heritage buildings. Results of the analysis chain are presented in terms of potential current damage for selected areas and buildings.
Located in Library / RBINS Staff Publications 2021
Article Reference Soil‑litter arthropod communities under pasture land use in southern Rwanda
Land use change caused by human activities is the main driver of biodiversity loss and changes in ecosystem functioning. However, less is known about how the conversion of a natural to pasture land favour the biological diversity of soil-litter arthropods to advance efective conservation plans and management systems. To fll the gap, this study focussed on soil-litter arthropod communities under a pasture land use in southern Rwanda. Data have been collected using pitfall traps and hand collection between April and June 2021. Sampled specimens of soil-litter arthropods have been identifed to order and family levels by using dichotomous keys. Further, the species name was given when the identifcation key was available, while the morphological description was provided in absence of the identifcation keys. Results indicated a total of 3013 individuals of soil-litter arthropods grouped into 3 classes, 13 orders, 46 families and 87 morpho-species. Coleoptera showed a high number of families, while higher abundance and the number of morpho-species were found for ants (Hymenoptera: Formicidae). Higher abundance of sampled soil-litter arthropods is a sign that the studied area ofers suitable habitat for soil-litter arthropods. However, less abundance found for some groups of soil-litter arthropods might be infuenced by the used sampling techniques which were not appropriate for them. We recommend surveys using multiple sampling techniques to maximize chances of capturing a wide range of soil-litter arthropods
Located in Library / RBINS Staff Publications 2022