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AN INTRODUCTION TO THE (MACRO) ALGAE OF BC
by Colin Bates University of British Columbia View Michael Hawkes Seaweed Photo Collection Many people are unaware that British Columbia is a veritable hot spot of seaweed biodiversity. At last count, there were approximately 650 macroalgal species found in waters of the Pacific Northwest (Scagel et al. 1989, Gabrielson et al. 2000). Of these, 530 are known to occur in B.C.! Why are so many people unaware of the diversity of seaweeds that inhabit British Columbia's waters and shores? Many initial encounters with seaweeds can be unpleasant, especially if you are wading your way into the ocean for a swim, or if you are trying to maintain your footing while scrambling around on the rocks. As well, detached seaweeds end up washing ashore and amassing into smelly decomposing piles. Seaweeds generally get a bad reputation in the press (if any at all). Books like "Killer Algae" (Meinesz, 1999), which describes the invasive nature of a green seaweed species called Caulerpa taxifolia, and talk of 'Harmful Algal Blooms" (a microalgal phenomenon) do not help! All of these factors contribute to the idea that seaweeds are a nuisance. Yet, it is my experience that seaweeds are most certainly not a nuisance, and instead are beautiful organisms with fascinating natural history, diverse economic uses, and essential ecological roles. I hope by the end of this article that you will agree! To begin our discussion, it is important to
know that seaweeds are a subset of a larger group known as the
algae. It is therefore useful to start off with a short discussion
about the nature of this larger group.
What are algae? When most people think of algae, they conjure a green scum on the side of a pond or fish tank, but in reality algae can be large or small, helpful or harmful, and believe it or not, stunningly beautiful and head-scratchingly interesting. Unlike plants and animals, the algae do not arise from a single common ancestor (a condition referred to as monophyly. Instead, they are a group composed of many lineages (they are polyphyletic; Graham & Wilcox 2000). Throughout the history of algal taxonomy, various characters have been invoked to describe this disparate group: simple bodied organisms, reproductive propagules lacking well-developed structures, as in flowers or cones, mostly aquatic, and generally photosynthetic. Yet, because the algae are polyphyletic and arising from various ancient ancestors, there are myriad exceptions to these characters as well as many taxa that fit these descriptions.
In reality, the tie that binds all algae together is a concept known as the 'serial endosymbiosis hypothesis' (Bermudes & Margulis 1985, Bhattacharya 2000), which suggests that the commonality between all algae is that, at one or more points in their lineage, they acquired photosynthetic abilities through either the uptake of a photoautotrophic bacteria (known as a primary endosymbiotic event), or through the uptake of a heterotroph that had previously taken up a photoautotrophic bacteria (a secondary endosymbiotic event). A current hot topic in algal phylogeny is determining whether there was one or two primary endosymbiotic events that give rise to red and green algae (e.g. Moreira et al. 2000). It is generally accepted that there were multiple secondary endosymbiotic events. With the advent of molecular tools, algal systematics is in the midst of a substantial re-working of these and other questions.
Molecular tools have also provided the opportunity to examine relationships between algae and land plants (Bhattacharya & Medlin 1998). Mounting evidence suggests that land plants are derived from an ancestor of the green algal order Charales (Michler & Churchill 1985, Surek et al. 1994). Land plants are excluded from algae because they do not conform to the character set described above; these plants have complex bodies, typically with flowers or cones, and are normally terrestrial. The study of algae is called phycology, from the Greek root phykos meaning algae. Algae are a vast group including many classes of unicellular and multicellular organisms. Below, I focus on the multicellular macrophytes, and in particular, the benthic marine macrophytes that most refer to as the seaweeds. What are Seaweeds? Seaweeds are a macroscopic subset of marine algae (as opposed to the microscopic subset known as phytoplankton). The west coast of British Columbia has a diverse flora and is home arguably to the widest variety of kelp (Order Laminariales) in the world. To read the rest of Colin's article on Seaweeds, click here (PDF).
Double Pompom Kelp (Elsenia arborea), photo by Colin Bates Search
the Algal Database at the UBC Herbarium (65,000 records)
Key References Gabrielson, Paul W., Thomas B. Widdowson, Sandra C. Lindstrom, Michael W. Hawkes and Robert F. Scagel. 2000. Keys to the Benthic Marine Algae and Seagrasses of British Columbia, Southeast Alaska, Washington and Oregon. Phycological Contribution Number 5. Department of Botany, University of British Columbia. 2000 Hawkes, MW. 1994. Benthic Marine Algal Flora (Seaweeds) of British Columbia: Diversity and Conservation Status. Chap. 11 In: Biodiversity in British Columbia: Our Changing Environment, edited by E. McCullum & L. Harding. Environment Canada: Vancouver. Lindstrom, SC, JL Olsen, & WT Stam. 1997. Postglacial recolonization and the biogeography of Palmaria mollis (Rhodophyta) along the northeast Pacific coast. Can. J. Bot. 75: 1887-1896. Lindstrom, SC, JP Houghton & DC Lees. 1999. Intertidal macroalgal community structure in southwestern Prince William Sound, Alaska. Bot. Mar. 42: 265-280. Nelson, WA., GA Knight, & MW Hawkes. 1998. Porphyra lilliputiana sp. nov. (Bangiales, Rhodophyta) a diminutive New Zealand endemic with novel reproductive biology. Phycological Research 46: 57-61. O'Clair, R. M., and S. C. Lindstrom. 2000. North Pacific Seaweeds. Plant Press, Juneau, xii + 162 pp. + 16 color plates. Scagel, RF, PW Gabrielson, DJ Garbary, L Golden, MW Hawkes, SC Lindstrom, JC Oliveira and TB Widdowson. 1993 (reprint and revision of 1989 edition). A Synopsis of the Benthic Marine Algae of British Columbia, Southeast Alaska, Washington and Oregon. Phycological Contribution no. 3: vi + 535 pp. Dept. of Botany, University of British Columbia: Vancouver. Scagel, R. F., P. W. Gabrielson, D. J. Garbary, L. Golden, M. W. Hawkes, S. C. Lindstrom, J. C. Oliveira and T. B. Widdowson. 1989 [ Reprinted 1993 with minor changes]. A Synopsis of the Benthic Marine Algae of British Columbia, Southeast Alaska, Washington and Oregon. Phycological Contribution Number 3. Department of Botany, University of British Columbia.
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Please cite this page as: Bates, Colin. 2004. An Introduction to the Algae of British Columbia. In: Klinkenberg, Brian.(Editor) 2004. E-Flora BC: Atlas of the Plants of British Columbia [www.eflora.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. |
Please cite these pages as:
Please cite these pages as: Author, date, page title. In: Klinkenberg, Brian. (Editor) 2009. E-Flora BC: Electronic Atlas of the Plants of British Columbia [eflora.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. [Date Accessed]
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