Of course, these surveys of bacterial diversity beg for
follow-up on many fronts. An understanding of the biology
of so many new uncultured human commensals at this
point will rely largely on inferences from the nearest
cultivated phylogenetic neighbors, but for phylotypes only
distantly related to known species such comparisons may
be of little use. Nevertheless, culture-independent
methods can further extend our knowledge of human commensal
flora. In an era of high-throughput DNA sequencing,
analyzing more clones from libraries generated using
carefully chosen primers that minimize amplification biases
should be a straightforward way of finding more species.
Examining libraries generated from several people is important
to expand the catalog of species found in these niches,
and begin to address the question of how the microbial flora
might vary between people [16].