5/11/15 CONCEPTS OF BIOLOGY. Biodiversity: types, importance, threats, and preservation. There are three major types of biodiversity

Transcription

1 BIOSC10 END OF SEMESTER ANNOUNCEMENTS Today Quiz (chapters 19-20) Last new material! Chapter 21 Wed- review Q12 (2 pts) + 6 pts for active participation Bring a complete draft of your take-home final questions You ll be working in groups of 3-5- at least one student should bring a laptop or tablet to type on and connect to the internet You ll be creating final exam questions and uploading them to a dropbox on Angel to share with the class Final exam: Wed 5/20, 12:40-2:40pm, normal room ~40 questions (~30 covering cumulative material, ~10 specific to chapters 12/13, 19, 20, 21) CHAPTER 20 REVIEW What are the four major levels in a food chain? How much energy from one level is transferred to the next? CHAPTER 19 REVIEW What does population growth look like when there are limited resources? Examples of density-dependent and density-independent population regulation? What are some strategies used by organisms to avoid predation? What are the three types of symbiosis, with examples? Where is the greatest species richness (biodiversity) on Earth? Why are keystone species important, and examples? Primary vs secondary succession CONCEPTS OF BIOLOGY Chapter 21 CONSERVATION AND BIODIVERSITY What is biomagnification? Is most of Earth s water fresh, or salt? What are biogeochemical cycles? Major components of the water and CO2 cycles? What is a dead zone? What are the major terrestrial and aquatic biomes? Major ocean zones? Biodiversity: types, importance, threats, and preservation There are three major types of biodiversity Habitat destruction through deforestation, especially of tropical rainforests as seen in this satellite view of Amazon rainforests in Brazil, is a major cause of the current decline in biodiversity FIGURE 21.1 surfspots-gps.com 1

2 The variety of ecosystems on Earth from coral reef to prairie enables a great diversity of species to exist What are possible consequences if a whole ecosystem disappears? FIGURE 21.3 Patterns of biodiversity Map= number of amphibian species Human health: Catharanthus roseus, the Madagascar periwinkle, has various medicinal properties. Among other uses, it is a source of vincristine, a drug used in the treatment of lymphomas Where are the biodiversity hot spots? FIGURE 21.4 FIGURE 21.5 Agriculture: The Svalbard Global Seed Vault is a storage facility for seeds of Earth s diverse crops Wild food sources: For ~1 billion people, aquatic resources provide the main source of animal protein; but since 1990, production from global fisheries has declined despite considerable effort, few fisheries on Earth are managed sustainably FIGURE

3 Wild seafood sources: v=9f93rsdzuhc Global climate change: Atmospheric CO2 levels fluctuate in a cyclical manner; however, burning of fossil fuels in recent history has caused a dramatic increase in the levels of CO2 in Earth s atmosphere FIGURE 21.7 The effect of global warming can be seen in the continuing retreat of Grinnell Glacier The mean annual temperature in Glacier National Park has increased 1.33 C since 1900 Habitat loss: An oil palm plantation in Sabah province Borneo, Malaysia, replaces native forest habitat that a variety of species depended on to live Loss of a glacier results in loss of summer meltwaters, reducing seasonal water supplies and affecting ecosystems FIGURE FIGURE 21.8 Overharvesting: especially aquatic species, but also bush meat Exotic species: brown tree snake, Boiga irregularis, is an exotic species that has caused numerous extinctions on the island of Guam since its accidental introduction in 1950 FIGURE

4 This Limosa harlequin frog, an endangered species from Panama, died from a fungal disease Another fungal pathogen, introduced from Europe, may be responsible for white-nose syndrome in bats The fungus is native to Africa and may have spread around the world by a commonly used laboratory and pet species: the African clawed frog, Xenopus laevis FIGURE FIGURE Change in biodiversity through time Extinction intensity as reflected in the fossil record has fluctuated throughout Earth s history FIGURE A sixth, or Holocene, mass extinction has mostly to do with human activities The dodo bird was hunted to extinction around 1662 FIGURE A typical species-area curve shows the cumulative number of species found as more and more area is sampled Also interpreted to show the effect on species numbers of destroying habitat Preserve/restore habitat FIGURE FIGURE Change human behavior National parks, such as Grand Teton National Park in Wyoming, help conserve biodiversity 4

5 Conservation International identified 34 biodiversity hotspots Change human behavior to reflect sustainable fishing practices: Although these cover only 2.3 percent of the Earth s surface, 42% of the terrestrial vertebrate species and 50% of the world s plants are endemic to those hotspots FIGURE Protect keystone species (wolves in Yellowstone National Park) Zoos and captive breeding programs help preserve many endangered species, such as this golden lion tamarin FIGURE FIGURE CHAPTER 21 REVIEW (REVIEW Q12 ON WED) What are the three types of biodiversity, and why is each important? Where on Earth are the major biodiversity hot spots? Why is biodiversity important? What are the major threats to biodiversity? How has biodiversity changed over time? How can biodiversity be conserved? 5