A phylogenomic approach to resolve the eukaryotic tree of life
The eukaryotic tree of life is constantly improving, but the phylogenetic relationships between the major supergroups as well as the evolutionary origin of several other deeply diverging clades remain unknown. Resolving the phylogenetic position of these ‘orphan’ lineages is important, because they represent missing evolutionary links between established groups. Telonemia is one such orphan taxon for which little is known. The group is composed of molecularly diverse biflagellated protists, often prevalent although not abundant in aquatic environments. Following a phylogenomic approach, we extracted 321 genes from transcriptomic/genomic data from each of more than 740 taxa representing all eukaryotic supergroups. This so far largest taxon sampling enabled us to build an exceptional clean dataset by detecting contaminants, endosymbiotic gene transfers, and paralogs, which can easily be overlooked in smaller-scale analyses. Our phylogenetic analysis of this dataset not only revealed the evolutionary origin of Telonemia but also resolved most of the deep evolutionary relationships among eukaryotes.
Host: Justyna Wolinska