9355121 Goff Many highly specialized parasites such as ant parasites, fungi that parasitize other fungi, and red algal parasites may have evolved from their hosts. Dr. Lynda Goff of University of California at Santa Cruz is testing this hypothesis in a group of red algae (Rhodophyta). Because of the extreme morphological reduction that occurs frequently in parasites, key morphological features required for detailed evolutionary analyses are often missing in parasites. In such cases, molecular data from DNA sequences promise abundant, comparative evidence for reconstructing phylogenetic relationships and thus inferring evolutionary origins. Red algae in various groups of the orders Gigartinales and Ceramiales are being studied, to test whether host-parasite pairs are also phylogenetic sister-groups, with major evidence expected from nuclear ribosomal DNA. The research will provide a direct test of what has been called Emery's Rule in biology, the hypothesized evolution of parasitic forms from their host species. In addition, the new molecular data when integrated with traditional morphological characters will help improve the taxonomy of several groups of marine red algae.
