ReferenField ecology of Caenorhabditis species
The findings of Félix and Duveau [4] demonstrate the
new kind of science that can now be done with C. elegans
and C. briggsae. Being able to return to a site and reliably
resample nematodes makes long-term studies of nematode
population genetics possible. The emerging next
generation technologies for rapid sequencing of small
genomes (the C. elegans genome is only 100 Mb) will
facilitate complete genetic analysis of individuals and
populations [6], permit tracking of polymorphisms
through space and time, and help reveal the selective
pressures on the whole genome; this will allow measurement
of the rates of migration between local populations,
permit quantification of the relative rates of outcrossing
and selfing, and thus reveal the population genetic
structure of C. elegans in detail. Similar ecosystems can
be surveyed worldwide to identify parallel study sites,
and the effects of climate and isolation by distance can be
examined. Experimental interventions - for example,
introduction of genetically tagged nematodes or manipulation
of the ecosystem by selective removal of one class
of transport host - are possible in these mesocosm-scale
environments. Metagenomic surveys will reveal the
interacting populations of microbes cohabiting with the
nematodes, and isolate cultures can be tested for positive
and negative interactions with nematode genotypes
found on the same fruit or isolated elsewhere, revealing
genotypic interactions between co-adapted nematode