Phylogeny and taxonomy of tropical, free-living dinoflagellates – species diversity research in a modern context

Phylogeny and taxonomy of tropical, free-living dinoflagellates – species diversity research in a modern context

Associate professor Niels Daugbjerg, Ph.D., Institute of Biology, University of Copenhagen

Tropical, free-living dinoflagellates are single-cell algae, which fascinate their observers with their unique structure and many special forms. Unfortunately the biological diversity of this group in the Indian Ocean has not been exhaustively researched; most studies, many of which are more than 50 years old, are based on dead cells. This means that knowledge of the diversity of species of particularly one of the main groups (dinoflagellates without an armour covering of vesicles, or cellulose plates) is deficient. When naked dinoflagellates die, they lose their cell shape and are no longer recognisable. The presence of armour covering, however, means that the cell shape is preserved. This is the reason why our knowledge of the theca-covered dinoflagellates is more detailed. In this project, which we plan to implement as part of the Galathea 3 expedition, we shall therefore collect water samples containing living cells in order to describe the species diversity of especially the dinoflagellates without the theca armour covering. The morphological descriptions (taxonomy) are closely connected with the examination of the genus relationships (phylogenetics) in order to achieve a more complete characterisation of the dinoflagellate community. The project is based on modern analytical methods, in which we apply genetic sequences and digital recording equipment mounted on microscopes for photographic documentation. The media through which the research will be disseminated include the Internet, where descriptions and images/video recording of dinoflagellates are made available in colour. The intention is to gather existing knowledge and own observations to generate a higher general level of appreciation of tropical, free-living dinoflagellates, which play an important role in the ecology of the vast expanses of the tropical seas.