Description: Das Projekt "Genetic microdiversity and ecology of protists" wird vom Umweltbundesamt gefördert und von Universite de Neuchatel, Institut de Biologie durchgeführt. Protists (eukaryotes excluding plants, animals and fungi) represent a major element on the Earth's biodiversity. They play a key role in all ecosystems through their contribution to processes such as nutrient cycling or photosynthesis. However, our knowledge of their diversity and biology is very limited, which hinders our understanding of the full diversity of live on Earth and the respective roles of different groups of organisms. In this project, we aim to get an accurate picture of the diversity of a model group of protists, the euglyphid testate amoebae, and to understand the evolutionary patterns and phylogenetic relationships among lineages. Recent research on unicellular eukaryotes has considerably changed our understanding of the diversity, evolution and biology of these microorganisms, but many open questions remain. One of these, which we address in this project, is the long-lasting but still unresolved debate referred to here as the 'cosmopolitanism theory': Based on the fact that free-living protists build enormous populations in nature, and also on their high dispersal capacities, it has been argued that most species are cosmopolitan, and can be found wherever suitable conditions for the growth can be met. A corollary of this postulate is that appearance of new species must occur in sympatry (i.e. within the same geographic region), and is therefore a rare event. Accordingly, a relatively small number of species should be found across all ecosystems on Earth. However, environmental surveys of protist genetic diversity are revealing year after year a considerable and mostly unknown diversity. The great amount of genetic data that are accumulating in databases raises the question of the exact roles of these mostly unknown organisms in ecosystems. Thus, there is a conflict between the low diversity of free-living protists that the cosmopolitanism theory predicts and the high taxonomic and supposed related functional diversity observed from environmental DNA surveys. Studying the huge diversity of eukaryotic microorganisms in a single project is not possible. We therefore decided to focus our investigation on a group of model organisms, the euglyphid testate amoebae. We will first determine the environmental genetic diversity within this group. Furthermore, we will evaluate, for a single species, Assulina seminulum, the correlation between geographical distance and genetic diversity. A third part of the project will be to assess the relative influences of environmental conditions and genetic diversity on the morphological diversity of species.
Types:
SupportProgram
Origin: /Bund/UBA/UFORDAT
Tags: Populationsdynamik ? Amöben ? Genökologie ? Bevölkerungswachstum ? Biologische Wirkung ? DNA ? Genetik ? Morphologie ? Nährstoff ? Ökologie ? Pflanzensamen ? Mikrobiologie ? Geoinformation ? Biogeografie ? Mikroökologie ? Ökologische Bestandsaufnahme ? Photosynthese ? Protozoen ? Verbreitungsgebiet ? Artenvielfalt ? Geoökologie ? Daten ? Wirkungsanalyse ? Mikroorganismen ? Pilz ? Tier ? Evolution ? Genetische Vielfalt ? Umweltkonflikt ? Ökologischer Faktor ? Ökosystem ? Population ? Datenbank ? Standortbedingung ? Gebiet ? Biodiversität ? Assulina seminulum ? Eukaryoten ? Wachstum [biologisch] ? Art [Spezies] ?
License: cc-by-nc-nd/4.0
Language: Deutsch
Time ranges: 2009-01-01 - 2011-12-31
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