Search results for "RSA"
showing 10 items of 4345 documents
Arable-weed flora and its pollen representation: A case study from the eastern part of France
2007
International audience; Local pollen deposition in human-influenced vegetation types is studied with the aim of establishing the relationship between arable-weed vegetation and its pollen representation as an aid in interpreting human presence and impact on vegetation from pollen assemblages. The study area is located in the Franche-Comté region, eastern part of France. The presence of plants within 100 m2 plots and their pollen representation in moss samples within the same plots was recorded from different crops and annual fallows. Patterns in the vegetation and pollen assemblages were investigated separately using principal coordinate analysis (PCoA). Procrustean co-inertia analysis (PCI…
Messinian Italian Bovidae revised: paleobiogeographic and biochronological implications
2021
Bovidae from the Messinian localities of Italian Peninsula are poorly known and documented except in the Monticino Quarry record (Brisighella, central Italy), which represents, therefore, a key loc...
SPECIES RICHNESS WITHIN FAMILIES OF FLOWERING PLANTS
1994
Variation in species and genus richness among families of flowering plants was examined with respect to four classification variables: geographical distribution, growth form, pollination mode, and dispersal mode. Previous studies have estimated rates of species proliferation from age and contemporary diversity. Here we found that the earliest appearances in the fossil record are correlated with contemporary familial species richness, abundance in the fossil record, and the independent variables considered in this analysis. Thus, we believe that the fossil record does not provide reasonable estimates of the ages of families and that the rate of species proliferation cannot be calculated from…
Give me a sample of air and I will tell which species are found from your region : Molecular identification of fungi from airborne spore samples
2017
Fungi are a megadiverse group of organisms, they play major roles in ecosystem functioning and are important for human health, food production and nature conservation. Our knowledge on fungal diversity and fungal ecology is however still very limited, in part because surveying and identifying fungi is time demanding and requires expert knowledge. We present a method that allows anyone to generate a list of fungal species likely to occur in a region of interest, with minimal effort and without requiring taxonomical expertise. The method consists of using a cyclone sampler to acquire fungal spores directly from the air to an Eppendorf tube, and applying DNA barcoding with probabilistic specie…
Staying cool: preadaptation to temperate climates required for colonising tropical alpine-like environments.
2018
Plant species tend to retain their ancestral ecology, responding to temporal, geographic and climatic changes by tracking suitable habitats rather than adapting to novel conditions. Nevertheless, transitions into different environments or biomes still seem to be common. Especially intriguing are the tropical alpine-like areas found on only the highest mountainous regions surrounded by tropical environments. Tropical mountains are hotspots of biodiversity, often with striking degrees of endemism at higher elevations. On these mountains, steep environmental gradients and high habitat heterogeneity within small spaces coincide with astounding species diversity of great conservation value. The …
Nest-mediated parental care in a marine fish: Are large-scale nesting habitats selected and do these habitats respond to small-scale requirements?
2018
Fishes have evolved various reproductive strategies including mechanisms that involve parental care and demersal eggs laid into nests. Symphodus ocellatus has a seasonal reproduction period during which large, dominant males become territorial and build nests with fragments of algae, where they attract females to spawn and provide care to the developing eggs. Based on the hypothesis that the S. ocellatus males choose the reproductive habitat based on some characteristics of the substrate, here we assessed whether, on a coastal area scale, the distribution of this species changes during the reproductive period because of the selection of some suitable sites or substrates, and whether the nes…
Sex-allocation conflict and sexual selection throughout the lifespan of eusocial colonies.
2018
AbstractModels of sex allocation conflict are central to evolutionary biology but have mostly assumed static decisions, where resource allocation strategies are constant over colony lifespan. Here, we develop a model to study how the evolution of dynamic resource allocation strategies is affected by the queen-worker conflict in annual eusocial insects. We demonstrate that the time of dispersal of sexuals affects the sex allocation ratio through sexual selection on males. Furthermore, our model provides three predictions that depart from established results of classic static allocation models. First, we find that the queen wins the sex allocation conflict, while the workers determine the max…
¿Qué formación didáctica recibe el futuro profesorado de clarinete en el grado superior? Reflexiones y propuesta curricular
2017
Successive education reforms of advanced-level music teaching have greatly increased the workload of future professionals. However, these reforms have not brought about curricular changes in the work situation, clearly related to teaching at different levels. This article offers a comparative analysis of the curricula of the different autonomous communities, and concludes with a number of suggestions on how to improve educational training for clarinet graduates.
Parallel diversifications of Cremastosperma and mosannona (annonaceae), tropical rainforest trees tracking neogene upheaval of South America
2018
Much of the immense present day biological diversity of Neotropical rainforests originated from the Miocene onwards, a period of geological and ecological upheaval in South America. We assess the impact of the Andean orogeny, drainage of Lake Pebas and closure of the Panama isthmus on two clades of tropical trees ( Cremastosperma , ca 31 spp.; and Mosannona , ca 14 spp.; both Annonaceae). Phylogenetic inference revealed similar patterns of geographically restricted clades and molecular dating showed diversifications in the different areas occurred in parallel, with timing consistent with Andean vicariance and Central American geodispersal. Ecological niche modelling approaches show phyloge…
Understanding processes at the origin of species flocks with a focus on the marine Antarctic fauna
2017
Species flocks (SFs) fascinate evolutionary biologists who wonder whether such striking diversification can be driven by normal evolutionary processes. Multiple definitions of SFs have hindered the study of their origins. Previous studies identified a monophyletic taxon as a SF if it displays high speciosity in an area in which it is endemic (criterion 1), high ecological diversity among species (criterion 2), and if it dominates the habitat in terms of biomass (criterion 3); we used these criteria in our analyses. Our starting hypothesis is that normal evolutionary processes may provide a sufficient explanation for most SFs. We thus clearly separate each criterion and identify which biolog…