Long-term objectives:
1) To apply in combination molecular and traditional systematic techniques to foster a clearer understanding of algal evolution and phylogeny
2) To improve personal skills in, as well as foster appreciation for, alpha taxonomy, while contributing to characterization of the Southern Hemisphere flora
3) To appreciate and document natural fluctuations in species composition of algal floras over extended periods of time and investigate the negative impact of fin-fish aquaculture on the local flora, using long-term algal biodiversity monitoring protocols.
International Collaborative Research:
1) Algal Life Global Audit - ALGA - Genome Canada & NBIF-funded initiative using an approach known as DNA barcoding to explore the true levels of macroalgal diversity on the planet.
2) Red Algal Tree of Life Project - RedToL - an NSF-funded (also NSERC supported in the Saunders Lab) initiative to establish a robust phylogenetic framework for red algae to serve as a foundation for a comprehensive taxonomic revision and to provide the basis for interpreting key innovations during red algal evolution.
i) Systematics. As in all groups of organisms, the many species of algae are organized into hierarchical classifications (genera, families, orders and classes). There is much practical, as well as theoretical, utility to this exercise, for when a system of classification is based on evolutionary relatedness (i.e., one in which the groupings of species into genera, families and orders consist of only commonly derived members), it provides a foundation on which researchers can construct ordered accounts of the flora and as a guide for those seeking to survey related species for economically useful compounds. Traditional algal classification is based on detailed aspects of vegetative and reproductive anatomy. This system was reasonably successful, but suffered two shortcomings: i) it failed for the many asexual lineages of algae, as well as for species for which life history patterns were not known; and, ii) it was framed within subjective evolutionary hypotheses known to be incorrect by today's evidence. Molecular Systematics provides Objective Hypotheses. Molecular tools are powerful for deriving phylogenies independent of the largely phenotypic characters on which traditional taxonomies are built. It is important to emphasize that molecular data are not the definitive word in taxonomic determinations and that they should not totally supplant more traditional emphases. They are, however, considered more objective and, therefore, more indicative of evolutionary significance, than are anatomical expressions that may be influenced by convergent evolution or the environment in the form of plasticity. They allow the researcher to set aside preconceptions, thereby providing an entirely new data set from which to view organismal relatedness.
We have generated considerable small-subunit ribosomal DNA data (SSU) for the various algal lineages and have completely restructured many perspectives on algal evolution and taxonomy at all levels. Despite the advances much work remains, particularly in confirming the results obtained and in resolving relationships left equivocal during these investigations (within some orders and most families the SSU is too conservative for phylogenetic inference). Currently, we are expanding our molecular data to include the large-subunit ribosomal DNA (LSU) and we are generally realizing substantial resolution at nodes where the SSU failed. In particular, trees constructed from this genomic region are resolving relationships within families of all orders being studied, and even within some genera. Furthermore, red algal (Rhodophyta) molecular systematics, a major emphasis in my research group, is limited to SSU research and the plastid-encoded large subunit of Rubisco. Generally, the SSU resolves earlier events, whereas as Rubisco elucidates recent events. The LSU will thus provide a third gene to test the hypotheses derived from the two previous genes, and our preliminary analyses indicate that it will bridge the gap in phylogenetic signal. A major objective in this research group is to compare traditional perspectives on the evolution of morphological and anatomical characters with indications from the molecular phylogenies. Support will be gained for traditional interpretations in some cases, whereas new hypotheses on character evolution and distribution will be posited in others. The merging of molecular and traditional data into an increasingly consistent phylogeny will lead to a natural classification for the various algal lineages. Phylogenetically sound classification will facilitate an understanding of the relationships among algae and enhance biogeographic and biodiversity studies.
ii) Alpha taxonomy. My personal interest in algal evolution provides a wonderful balance between field and laboratory research. I spend considerable time scouring the New Brunswick coast and collect in British Columbia annually. I also travel throughout Chile and Australia and, along with colleagues, have identified a number of new species that we are currently investigating, which tend to augment the research we do on the better-characterized flora of the Northern Hemisphere. Back in the laboratory the research involves light microscopic investigation to elucidate the cryptic features of reproductive anatomy that form the basis of traditional red algal systematics. In some cases plants are introduced into culture to resolve the reproductive features and ultimately to provide sufficient material for DNA extraction. The culturing of algal species provides an excellent opportunity to study their unusual life histories in detail and this is a component of my research that will continue into the future. I feel that the paucity of trained professionals in alpha taxonomy is alarming on a global level. My students and I, therefore, will continue improving our skills and knowledge in Alpha taxonomy by continuing to contribute to the characterization of two rich and diverse algal floras in the Southern Hemisphere and the Canadian Atlantic and Pacific floras. This aim is being met through a combination of field trips by members of my laboratory and myself, as well as through collections sent by colleagues in Australia and Chile. Samples can be fixed and/or pressed and returned to Canada for detailed anatomical investigation and also dried in silica gel to provide a valuable resource for molecular systematic research. This may seem to some an objective of questionable worth, but I have twice been approached by aquaculturalists owing to algal-related problems in NB. Their biologists identified the problem species and I subsequently received the offending material. In one case a red alga was misidentified as a brown (the latter as closely related to humans as to the former), and in the second a potentially offensive alga had not even been observed. We need to reintroduce organismal awareness to our young biologists.
iii) Algal biodiversity monitoring. Biological diversity is important to the maintenance of healthy ecosystems and also represents an essential component of a nation's resources. We aim to catalogue this diversity to assist in its conservation and utilization. The Bay of Fundy is one of the marine natural wonders of the World owing to its unique geography and corresponding tidal range. The intrinsic value of this system, combined with the socioeconomic realities of ecotourism, fisheries, and aquaculture, provide overwhelming justification for the monitoring and investigation of biodiversity in this environment to insure conservation of this resource. The algae, macrophytes and phytoplankton, form the base of marine food webs, oxygenate aquatic environments, represent an underutilized resource for harvest and aquaculture, and can be used as biological indicator species in the Bay of Fundy. Unfortunately, algal biodiversity can be impacted upon negatively (overall reduction and/or shift in composition) by factors such as global warming, increased environmental stress arising from fisheries and aquaculture activities, and by accidental introductions of invasive species. Conversely, macroalgae can foul fisheries and aquacultural (greatly reducing oxygen levels during darkness when respiration exceeds photosynthesis) netting, and phytoplankton blooms of nontoxic and toxic species can have devastating effects on marine animals. The effect of shifting algal diversity owing to environmental degradation and accidental introduction is exacerbating the harmful algal problems experienced by fishers and aquaculturalists. In consideration of the previous, the level of marine algal research in Atlantic Canada is critically inadequate. Routine monitoring of both macroalgal and phytoplankton diversity is essential to the long-term appreciation of this resource.
We have identified three locations with an exposed and a sheltered site each. To monitor each site we have devised a system of transect based stratified sampling (based on the natural zonation of the coastal habitat) to estimate percent cover of algal species on the beach (useful for a variety of standard statistical procedures). We are also compiling 'complete' species inventories during our trips so that we can apply a new type of analyses, Taxonomic Distinctness, which will allow us to compare our contemporary data to historical records for the region. Our intention is to maintain this program over a few decades. This project will, if supported in the long term, provide a valuable data set for understanding floristics in this important and unique region. NSERC's recent reallocation has highlighted the critical shortage of taxonomic experts capable of identifying the organisms that constitute Canada's biodiversity. The value of biodiversity to society is lost if the know-how to survey, identify, protect and access available species does not exist. Furthermore, long-term monitoring is essential if we are going to set a baseline for future comparisons and distinguish natural patterns of species fluctuations versus perturbations caused by human impact. Our routine monitoring of algal biodiversity in the Bay of Fundy is designed to address all of the previous issues.