Chapter 16 - Biodiversity PDF

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Chapter 16 - Biodiversity ● What are the 3 levels in which biodiversity exists? ○ ecosystem diversity: # or variety of ecosystems; different kinds of habitats in a given area. ○ species richness: # or variety of species in a given area; diversity of richness. ○ genetic diversity: the genetic variability within a species-differences in DNA composition among individuals. ● Why do we need organisms or biodiversity? ○ organisms provide us with food, clothing, shelter and products. i.e bacteria and fungi for alcohol, antibiotics/medicine, and cleaning environmental disasters (oil spills and wastewater). ● Is biodiversity evenly distributed? ○ yes ● How does biodiversity enhance food security? ○ pollination and pest-controls for us. “every third bite of food you take… thank a bee or another pollinator” -E.O Wilson. ● Know how biodiversity is important to drugs/medicines ○ Fungi helps create them. ● What in an ecosystems service? How do high levels of biodiversity influence ecosystems services? ○ environmental benefits that the ecosystem provides. We rely on these for clean water and air, soil stability (to prevent erosion), and soil fertility (biomatter and nutrient recycling. ● What is an endemic species? ○ only found at one location on this planet. ● What is the #1 cause of Biodiversity loss? Then describe the other 3 major causes (in order) that we discussed in class. ○ habitat destruction, fragmentation, and degradation. i.e removing native plants in a field to grow what we want. ○ introduced species (invasive/non-native): the introduction of foreign, exotic species into a new ecosystem, aka “biotic pollution.” i.e Nile Perch introduced to Lake Victoria (Africa) as a food source. was a predator in the lake and wiped out two endemic species, decreasing biodiversity and putting the food supply at risk. ○ overexploitation: many species become endangered or extinct because of deliberate efforts to eradicate, control, or connect them (includes illegal trade and commercial harvest of LIVE organisms). i.e American Bisons hunted for food and sport in the 1800s now extinct. Passenger pigeons, sea otter for pelts, and the North Atlantic Bluefin Tuna for sushi. ○ pollution. In the air, oceans (oil spills, plastics leading to marine entanglement), precipitation (acid rain), and forest fires....