Threats to Biodiversity Quiz PDF

QUIZ! RECALL THE SIXTH EXTINCTION 1. T/F Inbreeding allows for more genetic variation and thus What is the major difference between the sixth extinction and all the better survivability....

QUIZ! RECALL THE SIXTH EXTINCTION 1. T/F Inbreeding allows for more genetic variation and thus What is the major difference between the sixth extinction and all the better survivability. other mass extinction events in terms of: Agent of change? 2. T/F Species diversity is best quantified with species Other mass extinctions – natural causes richness alone. Sixth Mass Extinction - humans 3. T/F Biodiversity is the variety of all forms, levels, and Rate of change? Other mass extinctions – thousands to millions of years interactions of life. Sixth extinction – tens to hundreds of years (faster) 4. T/F All species have equal priority in conservation. 5. BONUS Tourism is a provisioning ecosystem service. Do mutations affect biodiversity positively or negatively? How do extinctions promote biodiversity? Remember how biodiversity changed after dinosaurs went extinct. RECALL THE SIXTH EXTINCTION According to Lester Brown, what are the two factors on Earth that we must stabilize in order for conservation efforts to be most effective? Stabilize climate Stabilize population Do you thing we are making progress with Lester Brown’s suggested solution? Why or Why not?  Low adaptability Habitat Loss Invasive Exotics Overexploitation RECALL IUCN RED LIST WHY ARE SOME SPECIES MORE Cospychus mindanensis Cospychus cebuensis Philippine Magpie-Robin VULNERABLE Black Shama THAN THE Whole Philippines Cebu only Low population size and growth Any except montane forests OTHERS Primary and secondary forests Habitat restriction or specialization Small geographic range  SMALL POPULATION SIZE HABITAT AND GEOGRAPHIC RESTRICTIONS = Lower genetic diversity Species cannot go elsewhere due to barriers and/or inability to survive in = Lesser chances of adapting to new environments different conditions Genetic drift (bottleneck, founder effect) Harmful genes might dominate Evolution does not start from scratch e.g. Black Shama & Philippine Eagle = restricted to primary and secondary forests CONSTRUCTION Movement barriers Habitat destruction Collision to human structures  NONDESTRUCTIVE DEFORESTATION MODIFICATION EFFECTS Soil erosion Agricultural lands Habitat loss Fire regimes Source of timber Ecosystem conversion Water consumption Alarming pace in Soil erosion tropical regions Global warming (due to carbon lost from cleared forests) DESERTIFICATION Overgrazing EFFECTS (by livestock) Habitat loss Excessive burning Ecosystem conversion Cultivation (soil erosion) Soil erosion Deforestation Climate change  COMMERCIAL EXPLOITATION SUBSISTENCE EXPLOITATION To meet the basic needs of the household $$$$ (food, shelter, clothing, fuel) Financial gain and wealth Rare species or products are more expensive Effects dependent on: *Community population with access to wildlife * Level of consumption RECREATIONAL EXPLOITATION INCIDENTAL EXPLOITATION Just for the fun of it! Includes hunting and tourism “Accidental”, “Bycatch” Other organisms are killed instead of the target species; May or may not be damaging to the environment Usually happens in fishing  CONSEQUENCES OF OVEREXPLOITATION Decreased population size Change in ecosystem dynamics Keystone species Dominant species Focus on OVEREXPLOITATION, not EXPLOITATION. INVASIVE SPECIES HOW ARE THEY INTRODUCED An organism that is not native to a particular area, and causes harm to it Stowaways Subsidence / Commerce Recreation Cane toad Clown knifefish (Rhinella marina) (Chitala ornata) Other ways: Aesthetics, Science, Biological Control, Habitat Change  IMPACTS OF INVASIVE SPECIES Population decrease of native species Hybridization Ecosystem Effects BIODIVERSITY HOTSPOTS Summary High biodiversity + High biodiversity loss There are 4 major threats to biodiversity: low adaptation to change, habitat loss, overexploitation, and invasive exotics Some species have lower adaptation capacity due to low population sizes and growth, small geographic ranges, and habitat restrictions These threats can result to extinction, and eventually, biodiversity loss. The rate of extinction and biodiversity losses may differ across space and time.