Life history diversity and molecular phylogeny in the Australian sea star genus Patiriella
Maria Byrne, Anna Cerra, Mike W. Hart, Mike J. Smith, 1999. "Life history diversity and molecular phylogeny in the Australian sea star genus Patiriella", The Other 99%: The Conservation and Biodiversity of Invertebrates, Winston Ponder, Daniel Lunney
Download citation file:
The sea star genus Patiriella in Australia has the greatest diversity of life histories known for the Asteroidea. While the adults have similar phenotypes and life styles, their larvae are highly divergent. Patiriella includes species with unmodified development through typical feeding bipinnaria an d brachiolaria larvae and several patterns of modified development through non-feeding planktonic, benthic or intragonadal brachiolaria. Comparative embryology and molecular phylogeny indicate that divergence of Patiriella was closely tied to developmental change. Phylogenetic analysis divided the Patiriella species into two clades. With feeding larvae representing the ancestral state for these sea stars, one clade exhibited one identifiable change in larval form, while the other clade exhibited four changes in larval form. Life history traits in Patiriella appear to have evolved freely, contrary to the widely assumed evolutionary conservatism of early development. The range of life histories exhibited by Patiriella appears unique to these sea stars and is an important resource for investigation of the evolution of development.