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See detailEvolutionary history of Leopoldamys neilli, a karst endemic rodent in Southeast Asia, and implications for its conservation
Latinne, Alice ULg; Waengsothorn, Surachit; Michaux, Johan ULg

Conference (2013, August 15)

In this study, we have investigated the phylogeography of Leopoldamys neilli, a Murinae rodent species endemic to limestone karsts in Southeast Asia, on the basis of mitochondrial and nuclear markers ... [more ▼]

In this study, we have investigated the phylogeography of Leopoldamys neilli, a Murinae rodent species endemic to limestone karsts in Southeast Asia, on the basis of mitochondrial and nuclear markers. Both mitochondrial and nuclear markers support a large-scale population structure of four main groups within L. neilli and a strong finer structure within each of these groups. A deep genealogical divergence among geographically close lineages is observed and denotes a high population fragmentation. Our findings suggest that the current phylogeographic pattern of this species results from the fragmentation of a widespread ancestral population and that vicariance has played a significant role in the evolutionary history of L. neilli during Plio-Pleistocene. This study revealed an unexpected high level of intraspecific diversity within L. neilli. Consequently, the four main L. neilli population groups should be considered as four distinct Evolutionarily Significant Units (ESUs) and require appropriate management and conservation plans. [less ▲]

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See detailThe evolutionary history of Pomacentridae: key innovation and pattern of diversification
Frederich, Bruno ULg

Scientific conference (2015, April 21)

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See detailEvolutionary history of the bank vole Myodes glareolus: a morphometric perspective
Ledevin, Ronan; Michaux, Johan ULg; Deffontaine, Valerie et al

in Biological Journal of the Linnean Society (2010), 100(3), 681-694

The bank vole experienced a complex history during the Quaternary. Repeated isolation in glacial refugia led to the differentiation of several lineages in less than 300 000 years. We investigated if such ... [more ▼]

The bank vole experienced a complex history during the Quaternary. Repeated isolation in glacial refugia led to the differentiation of several lineages in less than 300 000 years. We investigated if such a recent differentiation led to a significant divergence of phenotypic characters between European lineages, which might provide insight into processes of intraspecific differentiation. The size and shape of the first and third upper molars, and first lower molar, of bank voles genetically attributed to different lineages were quantified using an outline analysis of their occlusal surface. The three teeth present similar trends of decreasing size towards high latitudes. This trend, the inverse of Bergmann's rule, is interpreted as the result of a balance between metabolic efficiency and food availability, favouring small body size in cold regions. Molar shape appeared to differ between lineages despite genetic evidence of suture zones. A mosaic pattern of evolution between the different teeth was evidenced. The analysis of such phenotypic features appears as a valuable complement to genetic analyses, providing a complementary insight into evolutionary processes, such as selective pressures, that have driven the differentiation of the lineages. It may further allow the integration of the paleontological dimension of the bank vole phylogeographic history. (C) 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 681-694. [less ▲]

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See detailEvolutionary history of the common dormouse, Muscardinus avellanarius, in Europe. Implications for its conservation
Mouton, Alice ULg; Grill, Andrea; Krystufek, Boris et al

Scientific conference (2010, May 19)

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See detailEvolutionary history of the most speciose mammals: molecular phylogeny of muroid rodents.
Michaux, Johan ULg; Reyes, A.; Catzeflis, F.

in Molecular Biology and Evolution (2001), 18(11), 2017-31

Phylogenetic relationships between 32 species of rodents representing 14 subfamilies of Muridae and four subfamilies of Dipodidae were studied using sequences of the nuclear protein-coding genes Lecithin ... [more ▼]

Phylogenetic relationships between 32 species of rodents representing 14 subfamilies of Muridae and four subfamilies of Dipodidae were studied using sequences of the nuclear protein-coding genes Lecithin Cholesterol Acyl Transferase (LCAT) and von Willebrand Factor (vWF). An examination of some evolutionary properties of each data matrix indicates that the two genes are rather complementary, with lower rates of nonsynonymous substitutions for LCAT. Both markers exhibit a wide range of GC3 percentages (55%-89%), with several taxa above 70% GC3 for vWF, which indicates that those exonic regions might belong to the richest class of isochores. The primary sequence data apparently harbor few saturations, except for transitions on third codon positions for vWF, as indicated by comparisons of observed and expected pairwise values of substitutions. Phylogenetic trees based on 1,962 nucleotidic sites from the two genes indicate that the 14 Muridae subfamilies are organized into five major lineages. An early isolation leads to the clade uniting the fossorial Spalacinae and semifossorial Rhizomyinae with a strong robustness. The second lineage includes a series of African taxa representing nesomyines, dendromurines, cricetomyines, and the sole living member of mystromyines. The third one comprises only the mouselike hamster CALOMYSCUS: The fourth clade represents the cricetines, myospalacines, sigmodontines, and arvicolines, whereas the fifth one comprises four "traditional" subfamilies (Gerbillinae, Murinae, Otomyinae, and Acomyinae). Within these groups, we confirm the monophyly of almost all studied subfamilies, namely, Spalacinae, Rhizomyinae, Nesomyinae, Cricetomyinae, Arvicolinae, Sigmodontinae, Cricetinae, Gerbillinae, Acomyinae, and Murinae. Finally, we present evidence that the sister group of Acomyinae is Gerbillinae, and we confirm a nested position of Myospalacinae within Cricetinae and Otomyinae within Murinae. From a biogeographical point of view, the five main lineages spread and radiated from Asia with different degrees of success: the first three groups are now represented by a limited number of species and genera localized in some regions, whereas the last two groups radiated in a large variety of species and genera dispersed all over the world. [less ▲]

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See detailEvolutionary history of the wood mouse (Apodemus sylvaticus) in the Palearctic region, with emphasis on the colonization of the Orkney Islands and Iceland
Durieu, Benoit ULg; Michaux, Johan ULg

Poster (2014, December 12)

To improve our knowledge concerning the hypothesis of northern refugia during the last glaciation for European species, we have focused our study on the evolutionary history of the wood mouse (Apodemus ... [more ▼]

To improve our knowledge concerning the hypothesis of northern refugia during the last glaciation for European species, we have focused our study on the evolutionary history of the wood mouse (Apodemus sylvaticus) throughout its Palearctic distribution. In addition, we also studied the wood mice populations from Orkney Islands and Iceland in order to understand their ways of colonization in the Atlantic islands. We used different molecular markers (cytb mitochondrial gene and a mitochondrial pseudogene). A geometric morphometric analysis using a morphological marker (mandible) was also used. This work highlights the potential existence of new wood mice lineages in Western Europe. These would be genetically differentiated, probably due to a geographical separation of an ancestral population in different refugia situated in the Iberian Peninsula during the last glacial maximum. Morphological differences also exist between the wood mice lineages. However, the study did not bring any evidence concerning the existence of Nordic refugia for this species. Concerning the insular populations, our results seem to show that populations from Orkney Islands and Iceland are genetically close to the Great Britain populations. They would have been introduced in these islands by Vikings or by earlier human populations. Additional sampling in Western Europe and in the Atlantic islands will clarify the origins of these populations. [less ▲]

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See detailEvolutionary mechanisms in colonizing plant populations
Monty, Arnaud ULg

Conference (2012, November)

In a rapidly changing world, human activities offer opportunities for many plant species to colonize new areas. Increasingly, it is recognized that colonization can be accompanied by different ecological ... [more ▼]

In a rapidly changing world, human activities offer opportunities for many plant species to colonize new areas. Increasingly, it is recognized that colonization can be accompanied by different ecological and evolutionary processes, acting over relatively short periods of time. When populations colonize novel environments, individuals’ phenotypes will depend on a combination of different, non-exclusive processes, including phenotypic plasticity (PP), local adaptation (LA), environmental maternal effects (EME) and genetic drift (GD)(Monty and Mahy 2009b). Despite these processes have long been studied independently, few attempts have been made to simultaneously address the importance of those processes in plant colonization. Here, we present a set of related studies aiming at disentangling the role of PP, LA, EME and GD in Senecio inaequidens (Asteraceae) in southern France, where it was introduced at a single wool-processing site in the late 19th century. We used seeds from populations growing in contrasted climates to explore the phenotypic variation related to climate. We performed several common garden experiments (Monty et al. 2009, Monty and Mahy 2009a, 2010), as well as a reciprocal sowing experiment with gardens under Mediterranean and Pyrenean climates (Monty et al. in revision). We analyzed climatic phenotypic variation in germination, growth, reproduction, leaf physiology and survival. We characterized genetic structure in the studied populations using AFLP. We found consistent genetic differentiation in growth traits but no home-site advantage, thus weak support for LA to climatic conditions. In contrast, genetic differentiation showed a relationship to colonization history. PP in response to climate was observed for most traits, and it played a particularly important role in leaf trait variation. EME mediated by seed mass influenced all but leaf traits under harsh climate. Heavier, earlier-germinating seeds produced larger individuals that eventually produced more flower heads throughout the growing season. However in a milder climate, EME were negligible. Our different studies suggest that phenotypic variation in response to climate depends on various ecological and evolutionary processes associated with geographical zone and life history traits. Therefore, we argue that a “local adaptation vs. phenotypic plasticity” approach, as often considered in the literature, is not sufficient to fully understand what shapes phenotypic variation and genetic architecture of colonizing populations. References Monty, A., J.-P. Bizoux, J. Escarré, and G. Mahy. in revision. Rapid plant invasion in distinct climates involves different sources of phenotypic variation. PLoS ONE. submitted Monty, A., J. Lebeau, P. Meerts, and G. Mahy. 2009. An explicit test for the contribution of environmental maternal effects to rapid clinal differentiation in an invasive plant. Journal of Evolutionary Biology 22:917-926. Monty, A. and G. Mahy. 2009a. Clinal differentiation during invasion: Senecio inaequidens along altitudinal gradients in Europe. Oecologia 159:305-315. Monty, A. and G. Mahy. 2009b. Évolution des traits d’histoire de vie lors des invasions végétales. Biotechnologie, Agronomie, Société et Environnement 13:449-458. Monty, A. and G. Mahy. 2010. Evolution of dispersal traits along an invasion route in the wind-dispersed Senecio inaequidens (Asteraceae). Oikos 119:1563-1570. [less ▲]

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See detailEvolutionary mode, tempo, and phylogenetic association of continuous morphological traits in the aquatic moss genus Amblystegium
Vanderpoorten, Alain ULg; Jacquemart, A. L.

in Journal of Evolutionary Biology (2004), 17(2), 279-287

Evolutionary significance of morphological characters that have traditionally been used for species delineation in the aquatic moss genus Amblystegium was tested by partitioning the environmentally and ... [more ▼]

Evolutionary significance of morphological characters that have traditionally been used for species delineation in the aquatic moss genus Amblystegium was tested by partitioning the environmentally and genetically induced morphological variation and focusing on morphological evolution using comparative methods. Cultivation experiments under controlled condition showed that most of the morphological variation in nature resulted from plasticity. Information regarding genetically fixed morphological variation and genetic similarity derived from polymorphic inter-simple sequence repeat markers was combined into an explicit model of morphological evolution. Maximum likelihood estimates of the model parameters indicated that evolution of most characters tended to accelerate in the most recent taxa and was often independent from the phylogeny. Constraining the different characters to be independent from each other most often produced a less likely result than when the characters were free to evolve in a correlated fashion. Thus, the morphological characters that have traditionally been used to circumscribe different Amblystegium species lack the independence, diagnostic value for specific lineages, and stability that would be required for distinguishing different species. [less ▲]

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See detailAn evolutionary perspective on the economics of energy consumption: the crucial role of habits
Maréchal, Kevin ULg

in Journal of Economic Issues (2009), 43(1), 69-88

The climate change issue imposes us not only to change the way we produce and convert energy but also to modify current energy consumption patterns. A substantial body of literature has shown that our ... [more ▼]

The climate change issue imposes us not only to change the way we produce and convert energy but also to modify current energy consumption patterns. A substantial body of literature has shown that our behavior is often guided by habits. The existence of habits - not fully conscious forms of behavior - is important as it contradicts rational choice theory. Their presence thus calls for the setting of new instruments as it is difficult to expect consumers to be capable of exercising control over their consumption of energy in reaction to given incentives. This is further increased in our perspective where the current carbon-based Socio-Technical System constrains and shapes consumers' choices through structural, cultural, social and institutional forces. Habits being potentially "counterintentional," can be considered as a form of behavioral lock-in that may explain continued increase of energy consumption. Policies should thus specifically address the performance context of habits. [less ▲]

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See detailEvolutionary potential of the Fallopia spp. complex in Europe
Vanderhoeven, Sonia ULg; Krebs, Christine; Schaffner, Urs et al

Conference (2009)

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See detailEvolutionary relationships among higher fungi inferred from small ribosomal subunit RNA sequence analysis
Wilmotte, Annick ULg; Van De Peer, Yves; Goris, Anne et al

in Systematic & Applied Microbiology (1993), 16

The primary structure of the small ribosomal subunit RNA (SSU rRNA) was determined for 13 species belonging to 10 ascomycete families and for the basidiomycetous anamorphic yeast Rhodotorula glutinis. The ... [more ▼]

The primary structure of the small ribosomal subunit RNA (SSU rRNA) was determined for 13 species belonging to 10 ascomycete families and for the basidiomycetous anamorphic yeast Rhodotorula glutinis. The sequences were fitted into an alignment of all hitherto published complete or nearly complete eukaryotic small subunit rRNA sequences. The evolutionary relationships within the fungi were examined by construction of a tree from 87 SSU rRNA sequences, corresponding to 71 different species, by means of a distance matrix method and bootstrap analysis. It confirms the early divergence of the zygomycetes and the classical division of the higher fungi into basidiomycetes and ascomycetes. The basidiomycetes are divided into true basidiomycetes and ustomycetes. Within the ascomycetes, the major subdivisions hemiascomycetes and euascomycetes can be recognized. However, Schizosaccharomyces pombe does not belong to the cluster of the hemiascomycetes, to which it is assigned in classical taxonomic schemes, but forms a distinct lineage. Among the euascomycetes, the plectomycetes and the pyrenomycetes can be distinguished. Within the hemiascomycetes, the polyphyly of genera like Pichia or Candida and of families like the Dipodascaceae and the Saccharomycetaceae can be observed. [less ▲]

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See detailEvolutionary significance and trade-offs in life-history traits associated to ecological specialization and mating systems in the liverwort genus Radula Dumort.
Laenen, Benjamin ULg; Devos, Nicolas; Renner, Matt et al

Poster (2011)

Shifts in mating systems are amongst the most common and important transitions in plants and are correlated with a suite of life-history traits. The evolution of mating systems and their relationships to ... [more ▼]

Shifts in mating systems are amongst the most common and important transitions in plants and are correlated with a suite of life-history traits. The evolution of mating systems and their relationships to gametophyte size, sexual reproduction, formation of asexual diaspores, and ecological specialization, is examined here in the leafy liverwort genus Radula.More specifically, we attempt to answer the following questions:(1)What is the ancestral mating system in Radula? (2)Are shifts from one mating system to another directional or random? (3)How does the evolution of mating systems correlate with the evolution of other related life history traits and, in particular, the specialization to temporary habitats? (4)What are the contingence relationships and order of acquisitionof those traits? [less ▲]

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See detailEvolutionary status of the Of?p star HD 148937 and of its surrounding nebula NGC 6164/5
Mahy, Laurent ULg; Hutsemekers, Damien ULg; Nazé, Yaël ULg et al

in Astronomy and Astrophysics (2017), 599(A61), 17

<BR /> Aims: The magnetic star HD 148937 is the only Galactic Of?p star surrounded by a nebula. The structure of this nebula is particularly complex and is composed, from the center out outwards, of a ... [more ▼]

<BR /> Aims: The magnetic star HD 148937 is the only Galactic Of?p star surrounded by a nebula. The structure of this nebula is particularly complex and is composed, from the center out outwards, of a close bipolar ejecta nebula (NGC 6164/5), an ellipsoidal wind-blown shell, and a spherically symmetric Strömgren sphere. The exact formation process of this nebula and its precise relation to the star's evolution remain unknown. <BR /> Methods: We analyzed infrared Spitzer IRS and far-infrared Herschel/PACS observations of the NGC 6164/5 nebula. The Herschel imaging allowed us to constrain the global morphology of the nebula. We also combined the infrared spectra with optical spectra of the central star to constrain its evolutionary status. We used these data to derive the abundances in the ejected material. To relate this information to the evolutionary status of the star, we also determined the fundamental parameters of HD 148937 using the CMFGEN atmosphere code. <BR /> Results: The Hα image displays a bipolar or "8"-shaped ionized nebula, whilst the infrared images show dust to be more concentrated around the central object. We determine nebular abundance ratios of N/O = 1.06 close to the star, and N/O = 1.54 in the bright lobe constituting NGC 6164. Interestingly, the parts of the nebula located further from HD 148937 appear more enriched in stellar material than the part located closer to the star. Evolutionary tracks suggest that these ejecta have occured 1.2-1.3 and 0.6 Myr ago, respectively. In addition, we derive abundances of argon for the nebula compatible with the solar values and we find a depletion of neon and sulfur. The combined analyses of the known kinematics and of the new abundances of the nebula suggest either a helical morphology for the nebula, possibly linked to the magnetic geometry, or the occurrence of a binary merger. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.Based in part on observations collected at the European Southern Observatory, in Chile. [less ▲]

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See detailEvolutionary trends of swimbladder sound mechanisms in some teleost fishes
Parmentier, Eric ULg; Diogo, Rui

in Ladich, F.; Collin, S. P.; Moller, P. (Eds.) et al Fish Communication (2006)

Many teleosts are able to emit sounds with their swimbladder. This chapter reviews the various sonic mechanisms involving the swimbladder and the intrinsic and extrinsic muscles, comparing them from a ... [more ▼]

Many teleosts are able to emit sounds with their swimbladder. This chapter reviews the various sonic mechanisms involving the swimbladder and the intrinsic and extrinsic muscles, comparing them from a morphological, biochemical, morphofunctional and physiological point of view. Close attention is paid to the Siluriformes and Ophidiiformes in which different cases of parallelism and/or convergence are examined. [less ▲]

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See detailLes évolutions de l’offre en logement : de la désurbanisation au renouvellement urbain
Halleux, Jean-Marie ULg

Conference given outside the academic context (2003)

Detailed reference viewed: 12 (0 ULg)