The applicant would use this Polar Postdoctoral Fellowship to investigate the evolution of brooding in cold-water systems using Antarctic starfish (asteriid asteroids) as models. A phylogenetic tree for the family Asteriidae will be reconstructed, emphasizing Antarctic genera and species using morphological and as molecular data. Fossil taxa will be included in the tree permitting timing estimates for evolutionary events. Since brooding is thought to be strongly associated with the development of the Antarctic megafauna, comparison between the timing of evolutionary events and paleoclimatic changes should allow insight into this relationship. The distinctive adaptations in modern Antarctic-Southern Ocean marine invertebrates have intrigued biologists since the very earliest specimens were collected and led to rigorous discussion regarding the evolution of faunas in the region. The modern Antarctic benthic megafauna has been strongly associated with the development of the circum-Antarctic current following the separation of eastern Antarctica from Australia and the opening of Drake Passage about 25 to 30 million years ago. The proposed work seeks to reconstruct a phylogeny for the Asteriidae in order to address broad evolutionary questions in a major clade of Antarctic marine invertebrates, which are dominant members of the benthic megafauna. The phylogenetic reconstruction will focus on three primary evolutionary questions: (1) What is the timing of asteriid diversification relative to the formation of the circum-Antarctic current? (2) How did brooding evolve in asteriids and how many times has brooding evolved? Are brooding and other clade-related (e.g., taxon richness) factors related? and (3) are the polar (Arctic vs. Antarctic) asteriid faunas members of a single lineage or have they evolved independently? The resulting phylogeny for asteriid starfishes is expected to have far-reaching and broad impact on the field as an evolutionary framework is developed for information recovered from very disparate sources throughout biology, including experimental biology, ecology, and conservation biology.
