Ch10, Section 1: What is Biodiversity? Standards: SCSh2b, 3c, 4a, 9c Biodiversity- number of different species in a given area. Highest in areas that get lots of sunlight, moisture, and nutrients- like a tropical rainforest. Unknown! We know 1.7 million have been identified and named. Estimate greater than 10 million actually exist. Many unknown species live in rainforest, deep oceans, even cities. Which group of organisms make up the majority of the 1.7 million known species? Genetic diversity Different genes within all members of a population. Species diversity Number of different species in an area. Ecosystem diversity Variety of habitats, communities, and ecological processes within and btwn ecosystems. 1. Species are part of balanced cycles within ecosystems 2. Maintain genetic diversity 3. Provide products for human use 4. Ethical, aesthetic, and recreation uses 1. Species are part of balanced cycles within ecosystems All species depend on each other as food sources Keystone species- when removed from an ecosystem, the ecosystem collapses Named after center block in an arch that supports arch (see picture) Ex: sea otter, salmon, grey wolf (Yellowstone) Sea otters were killed almost to extinction in the 1800s for their fur. Sea otters eat sea urchins but since there were no sea otters, the sea urchin population grew exponentially. Sea urchins devoured kelp which was home to numerous species of fish and invertebrates. Without kelp the entire ecosystem suffered. Sea urchins devouring kelp stalk 2. Maintain genetic diversity Need diversity to keep population healthy. If all species are genetically identical then an environmental change could wipe out the population. Creates bottleneck effect Ex: Cheetahs- there are so few cheetahs left that they begin to inbreed and lose genetic diversity. Suffering from genetic disorders & disease. Before cheetahs were killed off there was a lot of genetic diversity. Cheetahs population killed rapidly Very few traits survived. 3. Provide products for human use A. Medicine 1/3 of drugs derived from plants Almost all antibiotics from chemicals in fungi Ex: see chart DrugOriginUse TaxolPacific yewAnticancer NovacaineCoca plantLocal anesthetic L-dopaVelvet beanTreatment of Parkinsons disease B. Food Eating food from rainforests ensures protection of the rainforest b/c it becomes an exporting industry Ex: chocolate Need to create hybrids so crop genes arent too pure. (pure genes=increased susceptibility to disease Many undiscovered and underutilized crops in developing countries that could be used to provide income. C. Clothing Ex: cotton, silk D. Shelter Ex: wood, rubber from rubber trees 4. Ethics, Aesthetics, Recreation Ethics- species have a right to exist Aesthetics- personal enjoyment; camping, picking wildflowers, hiking Recreation- fishing, swimming, boating Ecotourism- form of tourism that supports conservation efforts; enables developing countries to earn income.