Figure 2. Bayesian phylogenetic tree of 18S rRNA gene obtained from the Lake Pavin.

The Bayesian unrooted tree was inferred from an alignment of 88 sequences with a character sampling of 1511 nucleotides. The origin of phylotypes from lake Pavin and the number of clones are indicated after each of our underlined environmental sequences. A white circle symbol corresponds to the oxic zone and a black one to the oxycline. The numbers (given as percentages) above and below the nodes correspond to Bayesian Posterior Probabilities and bootstrap values calculated using the Neighbor-Joining method, respectively.