The previous nematode AToL was highly successful in mobilizing the community of nematode researchers and producing extensive datasets of ribosomal sequences from major and minor clades across the entire phylum. Our published and ongoing analyses demonstrate however that several important evolutionary radiations within the phylum cannot be adequately resolved with presently available data. We therefore propose to extend the collective results obtained during the first nematode AToL project by bringing to bear on these outstanding problems in nematode phylogeny a much wider range of data and methodologies.
During the first nematode AToL we have developed and tested a range of protocols
that allow us to start from extremely small amounts of nematode tissue and obtain
sequences from large numbers of orthologous genes with high information content
for phylogenetic analysis. We now propose to apply the two most successful and
robust among these protocols to a much wider range of species across the phylum
than was previously possible, emphasizing especially the areas of low resolution
that correspond mainly to the origins and early evolution of the whole phylum,
as well as the origins and early evolution of Rhabditida sensu lato, which is
a monophylum that includes most of the medically and economically important
parasitic nematode clades.
In addition to obtaining multigene data across the phylum but emphasizing these
major and as yet unresolved radiations, we will also bring together published
data and obtain new information for a breadth of other types of characters from
mitochondrial genes and genomes, morphological and ultrastructural studies,
as well as developmental lineages and patterns. Since truly phylum-wide study
and analysis of such character suites is not possible within the limited time
and resources of one project, we will focus specifically on those aspects for
which previous and ongoing research has shown the greatest direct relevance
to the unraveling of the major radiations.
This project will have major impacts on science and education by consolidating
the infrastructure creations and collaborations established during the first
nematode AToL project. It will moreover integrate and reciprocally inform a
much wider range of biological disciplines by targeted inclusion of mitochondrial,
morphological and embryological analyses.