FIG. 8.

Minimum evolution phylogenetic tree of eukaryotic 18S rRNA gene sequences showing the positions of early branching sequences. The tree was constructed with maximum likelihood criteria by using a GTR+I+G DNA substitution model with the variable-site gamma distribution shape parameter (G) at 0.7597, the proportion of invariable sites (I) at 0.0990, and the base frequencies and rate matrix for the substitution model suggested by Modeltest (59), based on 924 unambiguously aligned positions. For additional details see the legend to Fig. 5.