Search publications of the members of the Royal Belgian institute of natural Sciences
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Monitoring en Modellering van het cohesieve sedimenttransport en evaluatie van de effecten op het mariene ecosysteem ten gevolge van bagger- en stortoperatie (MOMO). Activiteitsrapport 1 januari 2017 – 30 juni 2017
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Redescription of Cichlidogyrus tiberianus Paperna, 1960 and C. dossoui Douëllou, 1993 (Monogenea: Ancyrocephalidae), with special reference to the male copulatory organ
- The flatworms of the genus Cichlidogyrus Paperna, 1960 (Monogenea: Ancyrocephalidae) are gill parasites of freshwater fish, affecting predominantly the family Cichlidae. Cichlidogyrus tiberianus Paperna, 1960 and Cichlidogyrus dossoui Doue¨llou, 1993 are among the most widely distributed species of the genus, occurring in several African river basins and infecting many different host species, including the economically important Nile tilapia Oreochromis niloticus (Linnaeus) and redbreast tilapia Coptodon rendalli (Boulenger). Despite their wide distribution, C. tiberianus and C. dossoui have so far been studied only by light microscopy. In this paper they are redescribed on the basis of scanning electron microscopy of newly-collected material. The new material was obtained from redbreast tilapia caught in the Luapula River (D. R. Congo). The haptoral sclerites and genitalia are redescribed and illustrated in detail. Special attention is given to the complex morphology of the male copulatory organ.
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Capacity building for the Monitoring, Reporting and Verficiation (MRV) of biodiversity and ecosystem services in Africa
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Dusty baseline: the merit of museum collections in biological invasion studies
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Spatial and seasonal variation of biomineral suspended particulate matter properties in high-turbid nearshore and low-turbid offshore zones
- Suspended particulate matter (SPM) is abundant and essential in marine and coastal waters, and comprises a wide variety of biomineral particles, which are practically grouped into organic biomass and inorganic sediments. Such biomass and sediments interact with each other and build large biomineral aggregates via flocculation, therefore controlling the fate and transport of SPM in marine and coastal waters. Despite its importance, flocculation mediated by biomass-sediment interactions is not fully understood. Thus, the aim of this research was to explain biologically mediated flocculation and SPM dynamics in different locations and seasons in marine and coastal waters. Field measurement campaigns followed by physical and biochemical analyses had been carried out from 2004 to 2011 in the Belgian coastal area to investigate bio-mediated flocculation and SPM dynamics. Although SPM had the same mineralogical composition, it encountered different fates in the turbidity maximum zone (TMZ) and in the offshore zone (OSZ), regarding bio-mediated flocculation. SPM in the TMZ built sediment-enriched, dense, and settleable biomineral aggregates, whereas SPM in the OSZ composed biomass-enriched, less dense, and less settleable marine snow. Biological proliferation, such as an algal bloom, was also found to facilitate SPM in building biomass-enriched marine snow, even in the TMZ. In short, bio-mediated flocculation and SPM dynamics varied spatially and seasonally, owing to biomass-sediment interactions and bio-mediated flocculation.
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Benthic and fish aggregation inside an offshore wind farm: Which effects on the trophic web functioning?
- As part of the energy transition, the French government is planning the construction of three offshore wind farms in Normandy (Bay of Seine and eastern part of the English Channel, north-western France) in the next years. These offshore wind farms will be integrated into an ecosystem already facing multiple anthropogenic disturbances such as maritime transport, fisheries, oyster and mussel farming, and sediment dredging. Currently no integrated, ecosystem-based study on the effects of the construction and exploitation of offshore wind farms exists, where biological approaches generally focused on the conservation of some valuable species or groups of species. Complementary trophic web modelling tools were applied to the Bay of Seine ecosystem (to the 50 km2 area covered by the wind farm) to analyse the potential impacts of benthos and fish aggregation caused by the introduction of additional hard substrates from the piles and the turbine scour protections. An Ecopath ecosystem model composed of 37 compartments, from phytoplankton to seabirds, was built to describe the situation “before” the construction of the wind farm. Then, an Ecosim projection over 30 years was performed after increasing the biomass of targeted benthic and fish compartments. Ecological Network Analysis (ENA) indices were calculated for the two periods, “before” and “after”, to compare network functioning and the overall structural properties of the food web. Our main results showed (1) that the total ecosystem activity, the overall system omnivory (proportion of generalist feeders), and the recycling increased after the construction of the wind farm; (2) that higher trophic levels such as piscivorous fish species, marine mammals, and seabirds responded positively to the aggregation of biomass on piles and turbine scour protections; and (3) a change in keystone groups after the construction towards more structuring and dominant compartments. Nonetheless, these changes could be considered as limited impacts of the wind farm installation on this coastal trophic web structure and functioning.
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Treeline and timberline dynamics on the northern and southern slopes of the Retezat Mountains (Romania) during the late glacial and the Holocene
- Abstract To investigate treeline and timberline dynamics in the Retezat Mountains (Romanian Carpathians), late glacial and Holocene sediment sequences from four lakes were studied. The south and north slopes of the mountain range were compared using two lakes from the north flank (Lake Brazi, 1740 m a.s.l. and Lake Gales, 1990 m a.s.l) and two from the south flank (Lake Lia, 1910 m a.s.l. and Lake Bucura, 2040 m a.s.l.). Macrofossil and stomata analyses were performed to assess changes in the local vegetation, supplemented by pollen, charcoal and loss-on-ignition analyses. Our results show that treeline reached Lake Brazi on the northern side during the late glacial (ca. 14,000 cal yr BP) and then Lake Gales between 11,000 and 10,800 cal yr BP. During the early Holocene the upper limit of closed forest, the timberline, reached and passed Lake Brazi and has stayed above it since, but it has never reached Lake Gales at 1990 m a.s.l. The expansion of Larix decidua in the late glacialand early Holocene around Lake Brazi is unique. Stomata and macrofossils of Abies alba are also more abundant in the northern records. On the southern flank, treeline reached Lake Lia at around 12,000 cal yr BP, and was either very close to or at the elevation of Lake Bucura between ca. 8600 and 3000 cal yr BP. Timberline reached Lake Lia at ca. 8000 cal yr BP, some 3000 years after Lake Brazi, only 170 m lower on the north slope. Local fire events delayed the advance of timberline around Lake Lia in the early Holocene in a dry continental climate. The surrounding forest was dominated by Picea abies with individuals of Pinus cembra and stands of P. mugo until about 3000 cal yr \BP\ when timberline retreated below the lake. Maximum elevation of timberline was attained between ca. 8000 and 3000 cal yr BP, after which it descended in response to climate cooling. Regional climate change appears to be the main driver of treeline dynamics, but it was modified by local climatic differences due to slope aspect. The first signs of human disturbance appeared ca. 4200 cal yr BP, when naturally open areas were used as alpine pastures. Human impact in the treeline ecotone, mainly burning and grazing, was intensified after ca. 2600 cal yr BP, contributing to the widening of the ecotone and the lowering of the timberline.
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Design of flying robots inspired by the evolution of avian flight
- Bionic design of flying robots based on natural models has become a hot topic in mechanical engineering. The research going on in this direction considers that there is a lot to learn from flying animals such as birds, insects, and bats, from walking on the ground to getting enough power to be airborne. To get an efficient design of flying robots, we must better understand the origin of flight. This paper focuses on the review of avian flight and its possible application in the design of flying robots. Different hypotheses have been proposed to tackle the origin and evolution of avian flight from cursorial dinosaurs to modern birds, including the famous ground-up and tree-down theories. During the past decade, discoveries of feathered and winged dinosaurs from Liaoning, China, strongly supported the theory that birds originated from theropod dinosaurs. The transition from running on the ground to maneuver in the sky involves various stages of flights and plumages, which can be now illustrated by several representative paravian dinosaurs from Liaoning. Those fossils provide good research bases for the design of flying robots. Microraptor is one of those important transitional stages in the evolution of flight. This paravian dinosaur is characterized by the presence of pennaceous feathers along both its arms and its legs, but how it could actually fly is still debated. It is of course difficult to evaluate the flight performances of an extinct animal, but aerodynamics of a four-wing robot can be developed to get some knowledge about its flying capacity. Fossil and living flying animals with different morphologies, stability, and control mechanism can be a source of inspiration for designing socially relevant products.
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Shaking the wings and preening feathers with the beak help a bird to recover its ruffled feather vane
- The feather of a bird consists of barbs which again comprise numerous barbules with micro-hooklets. This hierarchically organized feather structure provides a smooth vane to bear the load from the airflow; however, the feather vane is vulnerable to disruption by external pulling forces during collision with the branches of a tree and hitting some small obstacles in flight or strong turbulence. The feather is unable to carry the weight of the bird's body if the vane could not be recovered immediately. Here we discovered that the feather vane can be re-established easily by birds themselves. A bird can always recover its feather vane from ruffled state by shaking its wings and preening its feathers with its beak because of the cascaded geometries of barbs and barbules. This biophysical mechanism of self-healing suggests that the hierarchical vane structure can be used to design artificial feathers for a flapping robot.
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The oldest freshwater crabs: claws on dinosaur bones
- With approximately 1,500 extant species, freshwater crabs (Decapoda: Brachyura) are among the most diverse decapod crustaceans. nevertheless, their fossil record is extremely limited: only potamidae, potamonautidae and trichodactylidae are reported up to the eocene of the neotropics so far. this work documents unusually large decapod claws from the Upper Cretaceous (Campanian) continental deposits of Velaux and vicinity (southern France), in close association with large vertebrate remains. In addition to (1) the systematic assignment of these claws, the study addresses (2) the salinity trends in the deposit environment from its faunal assemblage and the elementary chemical patterns of fossils, and (3) the likely scenario for their auto/allochthony in the Velaux fuvial system. These claws belong to a new taxon, Dinocarcinus velauciensis n. gen. n. sp., referred to as Portunoidea sensu lato, a group of “true” crabs nowadays linked to marine systems. However, the faunal assemblage, the claw taphonomy and the carbonates Y/Ho signatures support their ancient freshwater/terrestrial ecology, making them the oldest reported continental brachyurans and extending the presence of crabs in freshwater environments by 40 Ma. Either as primary or as secondary freshwater crabs, the occurrence of these portunoids in Velaux is an evidence for the independent colonizations of continental environments by multiple brachyuran clades over time, as early as the campanian.
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Palaeopathology of Iguanodon specimens from Museums in Belgium and Britain, and a comparison with pathological rates in Hadrosauridae
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L’herpétofaune du site Ramsar des Monts Birougou (Gabon) : catalogue illustré des espèces.
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Le Rubané en Belgique : nouvelle chronologie céramique et synchronisation avec les régions voisines
- Blouet V., Bosquet D., Constantin C., Fock H., Ilett M., Jadin I., Klag Th., Petitdidier M.-P., Thomashausen L., 2021. « Le Rubané en Belgique : nouvelle chronologie céramique et synchronisation avec les régions voisines ». Bulletin de la Société préhistorique française, tome 118 (07-2021), n° 2 : 277-322 + 9 Annexes en ligne. / Résumé. Des analyses statistiques réalisées à partir de 165 ensembles céramiques de Belgique et du Limbourg néer¬landais, totalisant 5 101 éléments de décors, permettent de proposer une périodisation en six phases et treize stades à valeur chronologique pour le Rubané de la Meuse. Cette séquence peut être synchronisée avec celles établies pour la région de Langweiler, la Lorraine française et le bassin de la Seine, ce qui permet de mieux caractériser chaque style régional et de mesurer les interactions entre les différents groupes de la zone d’étude. Les premières implantations du Limbourg et de Hesbaye relèvent du style de Flomborn qui s’impose, au Rubané ancien, dans tout le bassin du Rhin. À partir de l’étape moyenne, sur le cours moyen de la Meuse et en Hainaut, le Rubané partage avec le plateau d’Aldenhoven des motifs constitués de bandes délimitées remplies d’impressions au poinçon qui définissent un style Rhin-Meuse. Au Rubané récent, la Belgique se distingue par des bandes très larges remplies d’impressions au poinçon ou, plus fréquemment, au peigne à dents multiples. Ce style particulier, pour lequel il est légitime de conserver le terme d’Omalien, se distingue encore au Rubané final par une proportion majoritaire de motifs curvilignes, alors que partout ailleurs, ce sont les thèmes rectilignes qui s’imposent. À ces époques, la Hesbaye et le Hainaut se montrent relativement peu sensibles aux influences du style de Cologne, qui prédomine en Rhénanie du Nord. Depuis le Rubané moyen et jusqu’au Rubané final, la Lorraine du Nord entretient des échanges soutenus avec les régions mosanes, ce qui se traduit par des transferts de style, principalement en rive gauche de la Moselle, et par l’im¬portation massive de lames en silex du Maastrichtien et du Campanien de Belgique. Au Rubané terminal, une rupture semble se produire au moment de la mise en place du groupe de Blicquy-Villeneuve-Saint-Germain, qui forme une même entité stylistique entre le bassin de la Seine et la Belgique, régions qui jusqu’alors n’entretenaient pratiquement aucun échange. – Mots-clés : Belgique, Bassin de la Meuse, Néolithique ancien, Rubané, décor céramique, sériation, chronologie, styles régionaux. = Abstract: This article presents a new relative chronology for the Linearbandkeramik (LBK) of the Meuse basin. Divided into six main phases, the sequence is based on analysis of decorated ceramics from sixteen sites in Belgium and two sites in Holland. Eleven of the Belgian sites are located in Hesbaye, the province with the densest LBK set¬tlement. The other five sites form an outlying group in Hainaut, a little over 100 km to the west. The two Dutch sites are located in southern Limburg, about 50 km north-east of Hesbaye. Fine-ware ceramics were coded for rim, main and intermediate decoration motifs, employing a classification system previously developed in work on the LBK in Lorraine, with particular attention paid to the various techniques used for impressed decoration. The new Meuse basin sequence was established using 165 assemblages containing at least eight decoration motifs, representing a total of 5 101 coded motifs. In a majority of cases, these assemblages were formed by grouping ceramics from lateral pits of houses. Correspondence analysis and hierarchical clustering were used to seriate the assemblages and to define phases and sub-phases. By comparing quantitative trends in decoration motifs, the new Meuse chronology can be synchronized with the Lang¬weiler (Aldenhoven plateau), Lorraine and Seine basin LBK sequences, not only enabling a finer characterization of each regional style but also enhancing the view of interactions between the different groups in the study zone. During the early LBK, the period that sees the first settlements in Hesbaye and north Lorraine, the Flomborn style pre¬vails throughout the Rhine basin. When this cultural entity breaks down, decoration evolves in each region in a different manner. In the middle LBK, the Langweiler area, Dutch Limburg and Belgium form a coherent complex, termed the Rhine-Meuse style, characterized by bands delimited by incised lines and filled with rows of point impressions, which is the majority decoration. In the Moselle basin, as in southern Hessia, the Main style prevails, predominately with bands filled with transverse, crossed or longitudinal incised lines, while in the Seine basin the Champagne region is closely linked in stylistic terms to southern Alsace. The late LBK sees further regional differences, notably with the appearance of the Leihgestern style on the upper course of the Lahn, in central Hessia, and the emergence of the Cologne style in the lower Rhine. The Belgian LBK remains relatively unaffected by these processes and maintains its originality by developing the excessively broad curvilinear motifs, composed of bands filled with incised lines or with multiple-tooth (three or more teeth) comb impressions. These motifs characterize the Omalian style. In north Lorraine, the Main style remains important but the region is now split into two, with on the right bank of the Moselle a strong presence of the Oberrhein-Pfalz style, whose epicentre lies in the Palatinate, and on the left bank a predominance of Omalian influences. These favoured stylistic relations are also reflected by the circulation of lithic raw materials: on the middle and lower course of the Moselle, most of the flint tool-kit is made from blades in Maastrichtian and Campanian flint, imported from the Meuse basin as semi-finished products. In return, one finds in Hainaut, on the site of Blicquy “Petite Rosière”, Moselle-type motifs in noticeably higher numbers than attested elsewhere in Belgium. In the same period, on the upper course of the Moselle, the LBK of south Lorraine is linked to northern Alsace, while the Champagne LBK maintains its preferential relations with south¬ern Alsace. Throughout the late LBK, there is only limited interaction and exchange between these two groups and the Meuse, lower Rhine and middle Moselle. In the final LBK, the situation is more difficult to assess because the documentation varies in quality from one region to another. At this time, the Langweiler area is apparently abandoned by the LBK, while the Omalian-style LBK still flourishes in Hesbaye and to a lesser extent in Hainaut. On the middle course of the Rhine, new cultural entities appear, with the emergence of the Hinkelstein group on the Neckar and in the northern Palatinate, and the development of the Plaidt style on the lower course of the Moselle, from the Rhine confluence up to Luxembourg. A particular style appears in north Lorraine, derived from the Oberrhein-Pfalz style, while in south Lorraine another original style develops, combining elements from southern and northern Alsace as well as from north Lorraine. In the Seine basin, the LBK spreads northwards and westwards out of Champagne, settling the middle and lower courses of the Aisne and Yonne. Here again, one sees the formation of an original style, characterized by T motifs and predominant use of two- or three-toothed combs, at a time when combs with four or more teeth are more frequently used on the Meuse. At this stage, there is virtually no exchange between the Meuse and the Seine, while the middle Moselle distances itself stylistically from the Omalian but still imports large numbers of blades in Campanian flint from Hesbaye. The preferential relations maintained between Belgium and north Lorraine during the LBK apparently cease in the ter¬minal LBK stage. At this time, the Blicquy-Villeneuve-Saint-Germain (BVSG) culture appears in the Seine basin and in Belgium, possibly slightly earlier in Hainaut than in Hesbaye. The emergence and subsequent development of this new stylistic entity represents a significant change, because there is relatively little evidence for contacts between Belgium and the Seine basin during the previous LBK phases. In the terminal LBK, the Moselle basin finds a new supply of raw material in the Secondary and Tertiary flint of Champagne. The early BVSG site of Reims-Tinqueux shows that this “economic” exchange is also accompanied by some stylistic interaction. – Keywords: Belgium, Meuse basin, Early Neolithic, Linearbandkeramik, ceramic decoration, seriation, chronology, regional styles. https://www.researchgate.net/publication/359112408_Le_Rubane_en_Belgique_nouvelle_chronologie_ceramique_et_synchronisation_avec_les_regions_voisines
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Ath "Les Haleurs", two villages LBK and Blicquy/Villeneuve-Saint-Germain: search For transition mechanisms through the integrated study of productions
- Solène Denis, Isabelle Deramaix, Nicolas Cayol, Benjamin Gehres, Éric Goemaere, Louise Gomart, Caroline Hamon, Ivan Jadin, Dimitri Teetaert, Martin Zeebroek, 2021. « Ath "Les Haleurs", two villages LBK and Blicquy/Villeneuve-Saint-Germain: search For transition mechanisms through the integrated study of productions ». Organisés par : Solène Denis, Louise Gomart & Peter Tóth, Crossed approaches to transitions in the Neolithic Understanding the social mechanisms underlying material culture transformation using the concept of chaîne opératoire Session 276, Theme 6. Material culture studies and societies, 27th Annual Meeting of the European Association of Archaeologists in Kiel, 8-11 sept., Germany, Kiel : programme & pré-acte.
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What is hampering current restoration effectiveness? - An EKLIPSE Expert Working Group report
- Report Summary Target 2 of the EU Biodiversity Strategy states that “By 2020, ecosystems and their services are maintained and enhanced by establishing green infrastructure and restoring at least 15% of degraded ecosystems”. The Biodiversity Strategy is the only EU policy document that contains a direct and quantitative target for restoration. However, many other European Union level policies, including the Birds and Habitats Directives, the Water Framework Directive, and the Common Agricultural Policy, relate to restoration aims in indirect ways. The need to upscale restoration effectiveness across the European countries could never be more urgent. Numerous recent key Reports have identified restoration as key to overcoming biodiversity and climate challenges (eg Diaz et al 2019, Arnet et al 2019). At the closing statement of the UNCCD COP14 Climate Action Summit in September 2019, the Executive Secretary Mr. Ibrahim Thiaw, stressed that land restoration, at proper scale, is one of the cheapest solutions to address the global crises of climate and biodiversity loss. As highlighted in the recent Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) Assessment Report on Land Degradation and Restoration (Scholes et al., 2018) Restoration actions occur across a diversity of ecosystem types and have the potential, if implemented effectively, to improve human well‐being, improve ecosystem functions and biodiversity and enhance the wider natural environment; Gaining a better understanding of the limitations to effective restoration can provide evidence to support more effective investments in restoration. This knowledge can also support stakeholders from wide ranging fields, with the outcomes being to reduce the degradation of landscapes. Reduced degradation provides opportunities to improve climate resilience and mitigation, improve food security and improve human well‐being. In this context, during the second call for requests (CfR.2/2017) the EKLIPSE project received a request from BiodivERsA15, focused on the identification of knowledge gaps on ecosystem restoration. More specifically, the requester wanted to know What is hampering the effectiveness of existing approaches that aim to restore biodiversity and ecosystem function and services? The topic of this request has gained high policy relevance and importance following the approval of the United Nations Decade on Ecosystem Restoration (2021 to 2030), by the General Assembly on the 1st March 2019. This initiative aims to promote the restoration of degraded or destroyed ecosystems globally as a means of combating the impact of climate change and biodiversity loss, and to increase food security and water supply. This offers an unprecedented opportunity from the European perspective to implement the findings from this Report, to advance restoration effectiveness across Europe in response to increasing global pressures to scale up restoration actions. To respond to this request, EKLIPSE selected 12 experts from 8 European countries (Czech Republic, Finland, Greece, Ireland, Netherlands, Portugal, Spain, United Kingdom and 1 non‐ European Country (Australia), to form an Expert Working Group (EWG), which initially met in Brussels in July 2018 and continued to meet remotely, on a weekly basis until the completion of the Report. Two distinct approaches were implemented to respond to this question: a scoping review of the global literature and a three stage Delphi process with additional European experts from a range of sectors and countries. The global literature scoping review identified three Key Barriers to effective restoration as: a. The lack of a long‐term monitoring of restoration outcomes. b. The lack of a clearer definition of goals and planning. c. The need for better research methodologies. with the Key Enabling factors being: a. Use of appropriate and well‐tailored restoration techniques. b. Societal integration with the restoration project. c. Success assessment and evaluation. The four Key Groupings of Barriers identified in priority order by the Delphi process were: 1. Insufficient funding. 2. Low political priority for restoration. 3. Conflicting interests of different stakeholders. 4. Lack of integrated land use planning. During the Delphi process Experts identified key solutions to overcome these Barriers (1‐4) above. Taking into consideration all the findings of our work, recommendations to overcome the barriers have been provided and grouped around the key groupings of barriers: 1. Resourcing and Incentives – make restoration possible. 2. Policy – make restoration count. 3. Society – make restoration a preferred option. 4. Knowledge ‐ make it into life‐long learning, link, network and facilitate use of knowledge. We hope you enjoy reading our Report and making use of our findings during upcoming restoration actions across Europe.
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The pan-and-tilt hyperspectral radiometer system (PANTHYR) for autonomous satellite validation measurements – prototype design and testing
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Pterosaur melanosomes support signalling functions for early feathers
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Radial porosity profiles: a new bone histological method for comparative developmental analysis of diametric limb bone growth
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Endocranial morphology of Liaoceratops yanzigouensis (Dinosauria: Ceratopsia) from Early Cretaceous Jehol Biota of Liaoning in China
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Is vertebral shape variability in caecilians (Amphibia: Gymnophiona) constrained by forces experienced during burrowing?
- Caecilians are predominantly burrowing, elongate, limbless amphibians that have been relatively poorly studied. Although it has been suggested that the sturdy and compact skulls of caecilians are an adaptation to their head-first burrowing habits, no clear relationship between skull shape and burrowing performance appears to exist. However, the external forces encountered during burrowing are transmitted by the skull to the vertebral column, and, as such, may impact vertebral shape. Additionally, the muscles that generate the burrowing forces attach onto the vertebral column and consequently may impact vertebral shape that way as well. Here, we explored the relationships between vertebral shape and maximal in vivo push forces in 13 species of caecilian amphibians. Our results show that the shape of the two most anterior vertebrae, as well as the shape of the vertebrae at 90% of the total body length, is not correlated with peak push forces. Conversely, the shape of the third vertebrae, and the vertebrae at 20% and 60% of the total body length, does show a relationship to push forces measured in vivo. Whether these relationships are indirect (external forces constraining shape variation) or direct (muscle forces constraining shape variation) remains unclear and will require quantitative studies of the axial musculature. Importantly, our data suggest that mid-body vertebrae may potentially be used as proxies to infer burrowing capacity in fossil representatives.
