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The vast resource of viral genome sequences has been exploited to carry out a genomic comparison and phylogenetic analysis of the picorna-like superfamily. The authors conclude that the diverse groups of picorna-like viruses probably evolved in a 'Big Bang' that came after the evolution of the main groups of eukaryotes.
Ley, Gordon and colleagues have analysed and compared published sequences of bacterial communities from humans with both free-living communities and those that are associated with diverse animals. They conclude that gut-associated microbiotas are profoundly different from other free-living microbiotas, and call for widespread sampling of the human gut microbiota to study how different cultures, lifestyles and technologies are impacting on the biodiversity within these fascinating communities.
The archaeal domain comprises two phyla, the Euryarchaeota and the Crenarchaeota. Phylogenetic and genomic analyses now show that mesophilic crenarchaeota should not be considered as crenarchaeota. Based on this, the authors advocate the creation of a third archaeal phylum, which they propose to name Thaumarchaeota (from the Greek 'thaumas', meaning wonder).