Life history evolution of marine invertebrates: New views from phylogenetic systematics

Established theories on the evolution of the diverse life histories of marine metazoans, specifically invertebrates, were developed in the absence of rigorous phylogenetic methods. With improved estimates of evolutionary relationships for various marine invertebrate groups, based on phylogenetic systematics, we can now critically evaluate the assumptions upon which these theories are based. Several studies emphasizing a phylogenetic systematics approach have recently examined the evolutionary transitions among reproductive traits and challenge us to reconsider the generality of the assumptions made about life history evolution. The results point towards exciting possibilities for a better understanding of the great diversity of reproductive and developmental modes we observe in marine invertebrates today.