Supplemental Lab Topic BIODIVERSITY Biology 211 Fall 2004

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1 Supplemental Lab Topic BIODIVERSITY Biology 211 Fall 2004 OBJECTIVES After this lab you should be able to 1) describe different patterns and types of biodiversity, 2) discuss reasons for conserving biodiversity, and 3) describe threats to biodiversity. INTRODUCTION This lab is intended to outline in general terms some of the principal themes to be encountered in the field of biological diversity. During lab you will use sources from the Internet to answer questions, complete tables, and prepare short reports for presentation to the class. The World Wide Web (WWW) is an easily accessible source of information. However, the WWW is, for the most part, not critically reviewed before material appears. Therefore, you should be prepared to evaluate these sites critically. Some criteria to consider when evaluating the WWW sources include authority or sponsor of the site, and the accuracy, objectivity, currency, and coverage of the information. Appendix A in your lab manual describes each of these criteria in more detail. PROCEDURES Put your answers to the lab questions on the accompanying worksheet sheet. Working in groups is encouraged, but each student needs to turn in his or her own worksheet sheet. What is Biodiversity? All life on earth is part of one great, interdependent system. It interacts with, and depends on, the non-living components of the planet: atmosphere, oceans, freshwaters, rocks, and soils. Humanity depends totally on this community of life--this biosphere--of which we are an integral part. Biological diversity, or biodiversity, is the variety of the world's organisms, including their genetic diversity and the assemblages they form. It is the blanket term for the natural biological wealth that undergirds human life and wellbeing. (World Resources Institute. What is biodiversity? [on-line] available ( 1. In your own words, define and compare different types of biodiversity. Use the following sites as resources.

2 Biodiversity Patterns Use the listed sites below to answer the following questions. Be sure to consult more than one site and compare differences in estimates Review the section labeled How Many Living Species Have Been Recorded 2. Compare the estimated number of species with the number of described species. 3 a) What the 5 taxonomic groups with the largest number of described species? b) What percentage does each of these five taxa contribute to the total number of species, assuming that there are 1.4 million described species? c) What taxonomic group has the fewest described species? 4. How did these results differ from your answers on your pre-lab assignment? Biodiversity Hotspots 5. What are biodiversity hotspots? As a group, check out one of the biodiversity hotspots sites and in your own words, describe the hotspot and the major threats to the area. (Note that the map shows only terrestrial habitats)

3 7. Briefly review the following sites and summarize your group s impressions of the differences and similarities of biodiversity between marine ecosystems and tropical forests. Marine systems (focuses on coral reefs) Tropical Forest Species Loss of Biodiversity Review the following passages. Note the references to research conducted by your course instructor, Dr. Andy Blaustein. Extinction is a natural phenomenon that has been occurring almost since life first evolved; it is the current rate of extinction that underlies the biodiversity crisis. Because we can only estimate the number of species currently existing, we cannot determine the actual rate of species loss or the real magnitude of the biodiversity crisis. We do know for certain that we are living in a time of a high rate of species extinction caused by a high rate of ecosystem degradation by single species, Homo sapiens. (Campbell, N. A., Reece, J.B., Lawrence, G. M Biology. Benjamin Cummings, CA.) Indeed, all indications are that we are standing at the opening phase of a mass extinction event that will be comparable in scale to the five great extinction episodes that have taken place in the history of life on Earth, the most recent being the loss of the dinosaurs some 65 million years ago. Impending extinction rates are at least four orders of magnitude faster than the background rates seen in the fossil record (May et al., 1995). That means on the order of 10,000 times higher, a frightening prospect to say the least. If allowed to continue, the current extinction episode, the first to be driven by the actions of a single species, could well eliminate between one third and two thirds of all species in the next century (e.g., Raven, 1990; Wilson, 1992; Stork, 1996; Pimm and Lawton, 1998), resulting in what Quammen (1998) has called a "Planet of Weeds" in which only the hardiest and most adaptable species survive. The much discussed "Declining Amphibian Phenomenon" may well be the opening salvo in such an extinction event, and is only more immediate and evident because it involves a group of organisms with permeable skins and a complex life cycle that make them more vulnerable to environmental perturbations than many others (e.g., Blaustein and Wake, 1990; Blaustein et al., 1994). However, as the pyramid of life begins to erode at its base, other components are very

4 likely to collapse as well. (Mittermeier, R., Mittermeier, C.G., Myers, N. Hotspots. [online] available ) Importance of Preserving Biodiversity 8. Use information from several of the following sites to complete the corresponding chart on your answer sheet, which lists 6 reasons for preserving biodiversity. Give one or two examples for each reason Define ecosystem services. As a group discuss whether you think it would be worthwhile to put an economic value on ecosystem services? Summarize your group s responses on why or why not? Discuss the following situation as a group and then summarize your discussion on the answer sheet: If you were responsible for putting a value on ecosystem services, how would you go about doing it? What questions would need to be answered, or what information would you need? How would you go about getting the information? Review the following sites: As a group, choose one of the following medicinal plants. Your group will then prepare a brief report (2-3 paragraphs) in which you describe the plant and its current or potential benefit as a medicinal for humans. Review more than one site to get sufficient information

5 Threats to Biodiversity 12. Use the following sites as resources to list threats to biodiversity. What are the three most prevalent threats? How does this list compare to the one made for the pre-lab assignment? As a group, choose one of the following invasive species, and prepare a brief report describing the species and its threat to the biodiversity of the Pacific Northwest. Before searching the Internet for information, review the following site: False-brome (Brachypodium sylvaticus), Cheatgrass (Bromus tectorum), Starthistle (Centaurea solstitialis L.), Gorse (Ulex europaeus), Scot s broom (Cytisus scoparius), Cordgrass (Spartina sp.), Reed canary grass (Phalaris arundinacea), Purple loosestrife (Lythrum salicaria), European green crab (Carcinus maenas).

Climate Change and Invasive Plants in the Pacific Northwest

Climate Change and Invasive Plants in the Pacific Northwest David W Peterson Becky K Kerns Ecosystem Dynamics and Environmental Change Team Threat Characterization and Management Program Pacific Northwest