Search results for " Lamarck"
showing 4 items of 4 documents
1793 - I BENI NATURALI DIVENTANO BENI CULTURALI
2009
Il 1793 fu l’anno in cui l’istruzione fu riformata in Francia. Erano passati quattro anni dalla Rivoluzione e si imponevano nuovi criteri per l’insegnamento delle Scienze Naturali, che dovevano diventare la base di una nuova cultura, più attenta a tutti i viventi e meno antropocentrica. Come emblemi del passato, le Chiese venivano chiuse, o dedicate ad altre funzioni: così stava per succedere alla Chiesa di Saint Sulpice a Parigi che, dopo una grande festa popolare di inaugurazione, doveva diventare Tempio della Filosofia. Il periodo era assai turbolento e pericoloso, tanto che fu in seguito chiamato Terrore. Il Governo stesso temeva distruzioni e atti di vandalismo, soprattutto verso due s…
Data from: Phylogenomics of Lophotrochozoa with consideration of systematic error
2021
Phylogenomic studies have improved understanding of deep metazoan phylogeny and show promise for resolving incongruences among analyses based on limited numbers of loci. One region of the animal tree that has been especially difficult to resolve, even with phylogenomic approaches, is relationships within Lophotrochozoa (the animal clade that includes molluscs, annelids, and flatworms among others). Lack of resolution in phylogenomic analyses could be due to insufficient phylogenetic signal, limitations in taxon and/or gene sampling, or systematic error. Here, we investigated why lophotrochozoan phylogeny has been such a difficult question to answer by identifying and reducing sources of sys…
Data from: Phylogenomics of Lophotrochozoa with consideration of systematic error
2016
Phylogenomic studies have improved understanding of deep metazoan phylogeny and show promise for resolving incongruences among analyses based on limited numbers of loci. One region of the animal tree that has been especially difficult to resolve, even with phylogenomic approaches, is relationships within Lophotrochozoa (the animal clade that includes molluscs, annelids, and flatworms among others). Lack of resolution in phylogenomic analyses could be due to insufficient phylogenetic signal, limitations in taxon and/or gene sampling, or systematic error. Here, we investigated why lophotrochozoan phylogeny has been such a difficult question to answer by identifying and reducing sources of sys…
Du vol des oiseaux à l'évolution des espèces animales
2013
National audience; Étienne-Jules Marey se range du côté des partisans de l’évolution des espèces expliquée par le transformisme (1809) de Jean-Baptiste Lamarck (1744-1829). Marey déplore cependant que Lamarck demeure « beaucoup trop vague dans ses explications lorsqu’il attribue les changements des organismes vivants à des circonstances extérieures. Entre un besoin qui se révèle et l’apparition d’une forme organique qui corresponde à un besoin, il y a une lacune que sa théorie n’a pas comblée » . D’où chez Marey, des interrogations et le désir dans son champ de compétences de relever quelques faits avérés de transformations d’adaptation des êtres vivants à de nouvelles conditions de vie.