The rules that shape community composition of free-living microorganisms is a major and unsolved question in biology. Over the last decades, a heated debate has taken place about the existence or not of geographically influenced patterns among protists and micro-organisms in general. Several factors potentially influence the dispersal and colonisation potential of organisms, including life history, ecological niche and particular evolutionary history. Because these traits differ markedly among protist groups, we hypothesize that geographical distribution of taxa differs accordingly. We will focus on a particular and well-defined microhabitat, the interstitial water associated with Sphagnum mosses, characterised by high moisture, low nutrient content and low pH, in order to reduce the variability of environmental filters.
The aim of this project is to determine (1) which groups are cosmopolitan and which not, and (2) which traits are correlated to high dispersal capacities.
Concretely, we will:
- Determine the distribution pattern of eukaryote phylotypes at different scales. (World, Europe, Switzerland) using Next Generation Sequencing (Illumina sequencing of SSUrRNA gene v9 region)
- Correlate community data to physicochemical and climatic data to evaluate environmental filters.
- Select and examine more precisely some key cosmopolitan and geographically restricted groups according to NGS’s results.
- Determine distribution at the species level using variable markers, taxon-specific PCR protocols and a classical cloning-sequencing approach.
- Identify the common traits of cosmopolitan and narrow endemic organisms (SEM, TEM, FISH, cultures).
- Characterise the “silent biosphere” with tRNA analysis, by comparison with diversity obtained through DNA sequencing.
- Find a wide range of distribution patterns
- Find significant differences among the selected groups
- according to their dispersal strategies
- In theory, small organisms with high encysting capacities, large population size and wide ecological niches should disperse further.
PhD: Is everything everywhere? A metabarcoding approach to protist biogeography. (Laboratory of soil Biology, University of Neuchâtel, Switzerland)
2009 - 2012
Master Thesis In Biogeosciences: Mineralogical description and approach of the potassium cycle in soils of a semi evergreen forest of Belize (Laboratory Soil and Vegetation, University of Neuchâtel, Switzerland)
2005 - 2008
Bachelor in Biology (University of Neuchâtel, Switzerland)