Skip to content. | Skip to navigation

Personal tools

You are here: Home

Search results

RSS Subscribe to an always-updated RSS feed.

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



































New items since



Sort by relevance · date (newest first) · alphabetically
Article Reference BIRDIE: A data pipeline to inform wetland and waterbird conservation at multiple scales
Introduction: Efforts to collect ecological data have intensified over the last decade. This is especially true for freshwater habitats, which are among the most impacted by human activity and yet lagging behind in terms of data availability. Now, to support conservation programmes and management decisions, these data need to be analyzed and interpreted; a process that can be complex and time consuming. The South African Biodiversity Data Pipeline for Wetlands and Waterbirds (BIRDIE) aims to help fast and efficient information uptake, bridging the gap between raw ecological datasets and the information final users need. <br /><br /> Methods: BIRDIE is a full data pipeline that takes up raw data, and estimates indicators related to waterbird populations, while keeping track of their associated uncertainty. At present, we focus on the assessment of species abundance and distribution in South Africa using two citizen-science bird monitoring datasets, namely: the African Bird Atlas Project and the Coordinated Waterbird Counts. These data are analyzed with occupancy and state-space models, respectively. In addition, a suite of environmental layers help contextualize waterbird population indicators, and link these to the ecological condition of the supporting wetlands. Both data and estimated indicators are accessible to end users through an online portal and web services. <br /><br /> Results and discussion: We have designed a modular system that includes tasks, such as: data cleaning, statistical analysis, diagnostics, and computation of indicators. Envisioned users of BIRDIE include government officials, conservation managers, researchers and the general public, all of whom have been engaged throughout the project. Acknowledging that conservation programmes run at multiple spatial and temporal scales, we have developed a granular framework in which indicators are estimated at small scales, and then these are aggregated to compute similar indicators at broader scales. Thus, the online portal is designed to provide spatial and temporal visualization of the indicators using maps, time series and pre-compiled reports for species, sites and conservation programmes. In the future, we aim to expand the geographical coverage of the pipeline to other African countries, and develop more indicators specific to the ecological structure and function of wetlands.
Located in Library / RBINS Staff Publications 2023
Inproceedings Reference Investigating the Gill-Oxygen Limitation Theory (GOLT) in the context of gill parasite diversification
Located in Library / RBINS Staff Publications 2023
Article Reference Diving into Diversity: The Complex Evolutionary History and Species Richness of the ‘sawfin barbs’ from Lake Edward and Adjacent Systems
Located in Library / RBINS Staff Publications 2023
Article Reference Under pressure: the relationship between cranial shape and burrowing force in caecilians (Gymnophiona)
Caecilians are elongate, limbless and annulated amphibians that, with the exception of one aquatic family, all have an at least partly fossorial lifestyle. It has been suggested that caecilian evolution resulted in sturdy and compact skulls with fused bones and tight sutures, as an adaptation to their head-first burrowing habits. However, although their cranial osteology is well described, relationships between form and function remain poorly understood. In the present study, we explored the relationship between cranial shape and in vivo burrowing forces. Using micro-computed tomography (µCT) data, we performed 3D geometric morphometrics to explore whether cranial and mandibular shapes reflected patterns that might be associated with maximal push forces. The results highlight important differences in maximal push forces, with the aquatic Typhlonectes producing a lower force for a given size compared with other species. Despite substantial differences in head morphology across species, no relationship between overall skull shape and push force could be detected. Although a strong phylogenetic signal may partly obscure the results, our conclusions confirm previous studies using biomechanical models and suggest that differences in the degree of fossoriality do not appear to be driving the evolution of head shape.
Located in Library / RBINS Staff Publications 2021
Inproceedings Reference Large old tropical trees as keystone biodiversity structures: the Life on Trees program
Association for Tropical Biology and Conservation annual meeting https://www.atbc2024.org Large old tropical trees as keystone biodiversity structures: the Life on Trees program Leponce Maurice1, Basset Yves2, Aristizábal-Botero Ángela1, Albán Castillo Joaquina3, Aguilar Rengifo Guillermo4, Barbut Jérôme5, Buyck Bart5, Butterill Phil6, Calders Kim7, Carrias Jean-François8, Catchpole Damien9, D’hont Barbara7, Delabie Jacques10, Drescher Jochen11, Ertz Damien12, Heughebaert André13, Hofstetter Valérie14, Leroy Céline15, Leveque Antoine16, Macedo Cuenca Victor4, Melki Frédéric17, Michaux Johan18, Ocupa Horna Luis19, Pillaca Huacre Luis3, Poirier Eddy20, Ramage Thibault21, Rougerie Rodolphe5, Rouhan Germinal5, Rufray Vincent17, Salas Guererro Marcos4, Scheu Stefan11, Schmidl Jürgen22, Silva Dávila Diana3, Valenzuela Gamarra Luis23, Vanderpoorten Alain18, Villemant Claire5, Youdjou Nabil1, Pascal Olivier17 1 Royal Belgian Institute of Natural Sciences, Vautier st. 29, Brussels, 1000, Belgium; 2 Smithsonian Tropical Research Institute, Panama; 3 Museo de Historia Natural, Universidad Nacional Mayor de San Marcos, Lima, Peru; 4 Servicio Nacional de Áreas Naturales Protegidas por el Estado, Ministerio del Ambiente, Peru; 5 Muséum national d'Histoire naturelle, Paris, France; 6 Biology Centre, Czech Academy of Sciences, České Budějovice,Czech Republic; 7 Ghent University, Belgium; 8 Université Clermont-Auvergne, Clermont-Ferrand, France; 9 Independent Consultant, Lima, Peru; 10 Centro de Pesquisas do Cacau – CEPEC, Itabuna, Brasil; 11 Göttingen University, Germany; 12 Meise Botanic Garden, Belgium; 13 Belgian Biodiversity Platform, Brussels, Belgium; 14 AGROSCOPE, Nyon, Switzerland; 15 AMAP (Univ. Montpellier, CIRAD, CNRS, INRAE, IRD), Montpellier, France; 16 PatriNat (OFB-CNRS-MNHN), Paris, France; 17 Fonds de Dotation Biotope Pour La Nature, Mèze, France; 18 Université de Liège, Belgique; 19 Centro de Investigación en Biología Tropical y Conservación, Piura, Perú ; 20 Independent entomologist, Cayenne, Guyane ; 21 Independent entomologist, Concarneau, France ; 22 Universität Erlangen-Nürnberg, Germany. ; 22 Jardín Botánico de Missouri, Peru E-mail: (presenting author): mleponce@naturalsciences.be The aim of the Life on Trees (LOT, www.lifeontrees.org) program is to generate baseline knowledge about the number of eukaryotic species that a single large mature tropical tree can host and to understand how these communities of organisms are assembled. The program is being undertaken in the Andean Amazon biodiversity hotspot. Our first project, LOT01 in the Andean foothills in 2022, located at 400m a.s.l., involved the study of a spectacular Dussia tessmannii tree (Fabaceae), towering at 50 meters in height and 45m wide. Our second project, LOT02 in the Andes in 2023, at 2450m a.s.l., focused on a 32-meter-tall Ficus americana subsp. andicola. Surveys were carried out by professional climbers, guided by experts of the different eukaryotic groups studied (plants, fungi, animals, protists). To better understand the contribution of different tree components (bark, leaves, fruits, flowers, living and dead wood) to overall tree biodiversity, we partitioned observations into communities based on vertical strata or microhabitat and will examine similarities and nestedness in the composition of these communities. Initial findings indicate that significant diversity is harbored by the individual tree at both locations (e.g., LOT01 vs LOT02: 42 vs 114 orchid species, 28 vs 28 fern species, 200+ vs 300+ bryophyte species, and 180 vs 100+ lichen species identified). These figures set world records for their respective elevations. This confirms that large old tropical trees are important pools of biodiversity, probably related to the variety of local microhabitats and tree age.
Located in Library / RBINS Staff Publications 2023
Article Reference Unveiling the above-ground eukaryotic diversity supported by individual large old trees : the “Life on Trees” integrative protocol
Large tropical trees are rightly perceived as supporting a plethora of organisms. However, baseline data about the variety of taxa coexisting on single large tropical trees are lacking and prevent a full understanding of both the magnitude of biodiversity and the complexity of interactions among organisms in tropical rainforests. The two main aims of the research program “Life on Trees” (LOT) are (1) to establish baseline knowledge on the number of eukaryote species supported/hosted by the above-ground part of a single tropical tree and (2) to understand how these communities of organisms are assembled and distributed on or inside the tree. To achieve the first goal, we integrated a set of 36 methods for comprehensively sampling eukaryotes (plants, fungi, animals, protists) present on a tropical tree. The resulting LOT protocol was conceived and implemented during projects in the Andean Amazon region and is proposed here as a guideline for future projects of a similar nature. To address the second objective, we evaluated the microclimatic differences between tree zones and tested state-of-the-art terrestrial laser scanning (TLS) and positioning technologies incorporating satellite and fixed base station signals (dGNSS). A marked variation in temperature and relative humidity was detected along a 6-zones Johansson scheme, a tree structure subdivision system commonly used to study the stratification of epiphytic plants. Samples were collected from these six zones, including three along the trunk and three in the canopy. To better understand how different tree components (e.g., bark, leaves, fruits, flowers, dead wood) contribute to overall tree biodiversity, we categorized observations into communities based on Johansson zones and microhabitats. TLS was an essential aid in understanding the complex tree architecture. By contrast, the accuracy of positioning samples in the tree with dGNSS was low. Comprehensively sampling the biota of individual trees offers an alternative to assessing the biodiversity of fewer groups of organisms at the forest scale. Large old tropical trees provide a wealth of microhabitats that encompass a wide range of ecological conditions, thereby capturing a broad spectrum of biodiversity.
Located in Library / RBINS Staff Publications 2023
Article Reference Contribution of omnidirectional flight traps to assess the ant (Hymenoptera: Formicidae) diversity in an agroforestry system.
Located in Library / RBINS Staff Publications 2023
Inproceedings Reference Canopy laser scanning to study the complex architecture of large old trees
Canopy laser scanning to study the complex architecture of large old trees Barbara D'hont1 , Professor Kim Calders1 , Professor Alexandre Antonelli6 , Dr. Thomas Berg7 , Dr. Karun Dayal1 , Dr. Leonard Hambrecht5 , Dr. Maurice Leponce2,3, Prof. Arko Lucieer5 , Olivier Pascal4 , Professor Pasi Raumonen8, Professor Hans Verbeeck1 1Q-ForestLab, Department of Environment, Ghent University, Ghent, Belgium, 2Royal Belgian Institute of Natural Sciences, Brussels, Belgium, 3Université Libre de Bruxelles, Brussels, Belgium, 4Fonds de Dotation Biotope Pour La Nature, France, 5School of Geography, Planning, and Spatial Sciences, University of Tasmania, , Australia, 6Royal Botanic Gardens, Kew, Richmond, Surrey, United Kingdom, 7ARAÇÁ Project, Nova Friburgo, Rio de Janeiro, Brazil, 8Faculty of Information Technology and Communication Sciences, Tampere University, Tampere, Finland Large trees are keystone structures providing multiple ecosystem functions in forests all around the world: they disproportionately contribute to forest biomass and biodiversity. Large trees can have an extremely complex structure, housing many epiphytes on their stem and branches. High point-density 3D point clouds, in which leaves and epiphytes in the tree can be distinguished, are useful to make the link between the distribution of organisms on the tree, the tree architecture and its microclimate. In addition, a comprehensive branching model can improve above ground biomass (AGB) estimates. Highly detailed, complete point clouds of large trees are, however, exceptionally difficult to derive. With terrestrial laser scanning, the state-of-the-art method to capture 3D tree structure, the plant material blocks the view of (or, occludes) the top part of the dense crown. Drone or airborne laser scanning data on the other hand, lacks detail in the subcanopy. Combining these two methods minimises occlusion; however, increased distance from the tree to the scanner still leads to a relatively low resolution of the canopy point clouds. To improve the level of precision of the tree point clouds, we introduce a new concept, called canopy laser scanning (CLS). With CLS, a laser scanner is operated statically inside the tree canopy, reducing the distance between the area of interest and the instrument. We lifted a high-end laser scanner (RIEGL vz-400(i)) inside the canopy of six large emergent trees. Four of these trees are located in different types of tropical rainforests in Colombia, Brazil and Peru. They are part of biodiversity programs in which organisms and their spatial distributions are studied (Life On Trees, Araçá). The two other trees are famous giants located in the wet temperate eucalypt forests of southern Tasmania. We will present the practical aspects of CLS, evaluate the extra value of using canopy scans, looking at occlusion and point cloud precision, estimate epiphyte cover and AGB. We demonstrate that canopy laser scanning opens up new opportunities in sciences in which multi-disciplinary teams perform in depth research on large individual trees.
Located in Library / RBINS Staff Publications 2023
Article Reference Chromosomal inversions from an initial ecotypic divergence drive a gradual repeated radiation of Galápagos beetles
Island faunas exhibit some of the most iconic examples where similar forms repeatedly evolve within different islands. Yet, whether these deterministic evolutionary trajectories within islands are driven by an initial, singular divergence and the subsequent exchange of individuals and adaptive genetic variation between islands remains unclear. Here, we study a gradual, repeated evolution of low-dispersive highland ecotypes from a dispersive lowland ecotype of Calosoma beetles along the island progression of the Galápagos. We show that repeated highland adaptation involved selection on multiple shared alleles within extensive chromosomal inversions that originated from an initial adaptation event on the oldest island. These highland inversions first spread through dispersal of highland individuals. Subsequent admixture with the lowland ecotype resulted in polymorphic dispersive populations from which the highland populations evolved on the youngest islands. Our findings emphasize the significance of an ancient divergence in driving repeated evolution and highlight how a mixed contribution of inter-island colonization and within-island evolution can shape parallel species communities.
Located in Library / RBINS Staff Publications 2023
Article Reference Annotated type catalogue of Orthalicoidea (Mollusca, Gastropoda) in the Natural History Museum, London: A supplement
Located in Library / RBINS Staff Publications 2024