We are studying the phylogeny of the gastropod superfamily Trochoidea in order to understand the origin of marine biodiversity in tropical oceans.
To understand the evolution, ecology or biogeography of organisms we must first know how they relate to each other.
We are studying the relationships between gastropod superfamily Trochoidea. The Trochoidea contains more than 2,000 species found in all oceans of the world, at all latitudes, from the high intertidal to the ocean abyss.
Although the Trochoidea have been well studied over the last century, the systematics of the group is still unresolved.
Robust phylogenies are useful for determining the processes that contribute to the high levels of biodiversity within the tropical oceans. We are focusing on the Indo-West Pacific Ocean which harbours some of the world's highest levels of marine biodiversity, particularly of shallow water marine invertebrates.
We are interested in the origin of this diversity and the timing of its appearance to find out which global, regional and local factors have been the most important in shaping the world’s marine diversity.
CT scan of a South African species, Spectamen multistriatum, with the shell of the adult and soft tissues peeled away to see shells of the juveniles brooding in the mantle cavity © Lauren Howard.
Using molecular techniques such as sequencing of nuclear and mitochondrial DNA markers and whole mitochondrial genomes, we are converging on a phylogenetic hypothesis for Trochoidea and its encompassing clade Vetigastropoda.
We have investigated the evolutionary lineages of the rocky-shore genus Lunella, finding that one well known species can in fact be split into seven distinct species. To further differentiate some of these species, we are using next-generation sequencing techniques.
In the Trochoidea family Solariellidae, our sequencing studies have unearthed more than 50 new species and three new genera, as well as redefining three existing genera.
We are now describing these new species, making particular use of shell characteristics as seen under a scanning electron microscope.