David Singer

Nebela gimlii

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:

  1. Determine the distribution pattern of eukaryote phylotypes at different scales. (World, Europe, Switzerland) using Next Generation Sequencing (Illumina sequencing of SSUrRNA gene v9 region)
  2. Correlate community data to physicochemical and climatic data to evaluate environmental filters.
  3. Select and examine more precisely some key cosmopolitan and geographically restricted groups according to NGS’s results.
  4. Determine distribution at the species level using variable markers,  taxon-specific  PCR  protocols  and  a  classical cloning-sequencing approach.
  5. Identify the common traits of cosmopolitan and narrow endemic organisms (SEM, TEM, FISH, cultures).
  6. Characterise the “silent biosphere” with tRNA analysis, by comparison with diversity obtained through DNA sequencing.

Expected results

  • 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.


Contact: David Singer
Rue Daniel Jeanrichard 35
2400 Le Locle
Tel: 0041792182426
Mail: david.singer@unine.ch

personal site
Research Gate



2013 -

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)