Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
Peer Reviewed
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 ▲]

Detailed reference viewed: 49 (0 ULg)
Full Text
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 ▲]

Detailed reference viewed: 41 (5 ULg)
Full Text
Peer Reviewed
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 ▲]

Detailed reference viewed: 5 (0 ULg)
Peer Reviewed
See detailEvolutionary potential of the Fallopia spp. complex in Europe
Vanderhoeven, Sonia ULg; Krebs, Christine; Schaffner, Urs et al

Conference (2009)

Detailed reference viewed: 19 (0 ULg)
Peer Reviewed
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 ▲]

Detailed reference viewed: 49 (1 ULg)
Full Text
Peer Reviewed
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 ▲]

Detailed reference viewed: 13 (3 ULg)
Full Text
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 ▲]

Detailed reference viewed: 71 (8 ULg)
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: 7 (0 ULg)
See detailLes évolutions du phénomène urbain : précision des concepts et modélisation
Halleux, Jean-Marie ULg

Conference (2001, February 28)

Detailed reference viewed: 1 (0 ULg)
Full Text
Peer Reviewed
See detailEvolutions et changement de paradigme dans la fonction publique fédérale belge
Piron, Damien ULg

in Revue de la Faculté de Droit de l'Université de Liège (2012), 4

Detailed reference viewed: 52 (7 ULg)
Full Text
See detailÉvolutions multiples et intérêts nouveaux en matière de climatologie depuis 1970.
Erpicum, Michel ULg

Scientific conference (2014, February 25)

Evolution of the knowledge of the main variables of the climates of the Earth according to the recent evolution of the principal tools of climatology and instrumental data coming from international or ... [more ▼]

Evolution of the knowledge of the main variables of the climates of the Earth according to the recent evolution of the principal tools of climatology and instrumental data coming from international or national networks or from experimental measurements conducted in Climatological or Meteorological Institutes. [less ▲]

Detailed reference viewed: 59 (12 ULg)
Full Text
Peer Reviewed
See detailAn Evolutive Software Environment for Teaching the Finite Element Method in Electromagnetism
Dular, Patrick ULg; Geuzaine, Christophe ULg; Genon, André ULg et al

in IEEE Transactions on Magnetics (1999), 35(3), 1682--1685

Detailed reference viewed: 35 (0 ULg)
Peer Reviewed
See detailAn Evolutive Software Environment for Teaching the Finite Element Method in Electromagnetism
Dular, Patrick ULg; Geuzaine, Christophe ULg; Genon, André ULg et al

in Proceedings of the Eighth Biennal IEEE Conference on Electromagnetic Field Computation (1998)

Detailed reference viewed: 10 (0 ULg)
Full Text
Peer Reviewed
See detailEVOLVE: entre déception et optimisme
DELANAYE, Pierre ULg; Krzesinski, Jean-Marie ULg; CAVALIER, Etienne ULg

in Néphrologie & Thérapeutique (2013), 9(4), 241-245

Detailed reference viewed: 14 (6 ULg)