0000000000322822
AUTHOR
Thérèse Choné
Characterization of the 3D information of Calyptogena shells
We propose in this paper an application of multiresolution analysis techniques to extract information contained in the growth increments of a bivalve mollusk called: Calyptogena . The first stage consists in extracting a range image of the mollusk’s shell using a 3-D scanner. Applying a multiresolution analysis enables us to localize precisely those growth increments by preserving relevant details. Moreover, interesting spatial and frequency properties of the multiresolution analysis underline information contained on the shell. Intra-individual variation and inter-individual variations are compared to assume some conclusions as for the ontogenetic evolution of the animal such as periodicit…
La notion d'espace morphologique,outil d'analyse de la morphodiversité des organismes
Resume L'analyse de la morphologie des organismes est une base essentielle dans la mise en evidence des changementsevolutifs. La morphologie est maintenant frequemment abordee par des procedures quantitatives, dont certaines permettent de construire de veritables cartes morphologiques ou les dissemblances et ressemblances de formes entre les organismes sont directement lisibles et quantifiees. La notion d'espace morphologique, illustree ici par differents exemples, se revele particulierement feconde pour comprendre comment la diversite morphologique d'un ensemble d'organismes (stades ontogenetiques, populations, clades) se structure, et par consequent pour interpreter en termes evolutifs ou…
Effect of storage and composting on the properties and degradability of cattle manure
Abstract Stockpiling or thermophilic composting of cattle manure resulted in significant carbon losses of 17% and 26.4% and relative nitrogen gains of 25% and 32.7% for stockpiled and composted manure, respectively. As a consequence, C/N ratios decreased with increasing time of storage or composting. However, neither the pH nor the mineral nitrogen and organic carbon contents of the 0–50 μm fractions were significant indicators of the transformations of these materials. The degradability of the manure was measured by incubation for 2 weeks in a brown calcareous soil, following 1 week of preincubation. The biodegradation index (BI) or the proportion of CO 2 released from the amended soil in …
Biodiversity of Antarctic echinoids: a comprehensive and interactive database
Eighty-one echinoid species are present south of the Antarctic Convergence, and they represent an important component of the benthic fauna. “Antarctic echinoids” is an interactive database synthesising the results of more than 100 years of Antarctic expeditions, and comprising information about all echinoid species. It includes illustrated keys for determination of the species, and information about their morphology and ecology (text, illustrations and glossary) and their distribution (maps and histograms of bathymetrical distribution); the sources of the information (bibliography, collections and expeditions) are also provided. All these data (taxonomic, morphologic, geographic, bathymetri…
Morphological and genetic analyses reveal a cryptic species complex in the echinoid Echinocardium cordatum and rule out a stabilizing selection explanation.
14 pages; International audience; Preliminary analyses revealed the presence of at least five mitochondrial clades within the widespread sea urchin Echinocardium cordatum (Spatangoida). In this study, we analyzed the genetic (two mitochondrial and two nuclear sequence loci) and morphological characteristics (20 indices) from worldwide samples of this taxon to establish the species limits, morphological diversity and differentiation. Co-occurring spatangoid species were also analyzed with mitochondrial DNA. The nuclear sequences confirm that mitochondrial lineages correspond to true genetic entities and reveal that two clades (named A and B1) hybridize in their sympatry area, although a more…