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BIODIVERSITY = biological diversity

For a landscape of many ecosystems to perpetuate over time, there must be a diversity of species within each ecosystem, a diversity of ecosystems, and a diversity of successional stages within each ecosystem type Alpha diversity : many different species within an ecosystem type

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BIODIVERSITY = biological diversity

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  1. For a landscape of many ecosystems to perpetuate over time, there must be a diversity of species within each ecosystem, a diversity of ecosystems, and a diversity of successional stages within each ecosystem type • Alpha diversity: many different species within an ecosystem type • Beta diversity: the difference in species composition among ecosystems • Gamma diversity: the total diversity of organisms over a landscape of ecosystems

  2. BIODIVERSITY = biological diversity • Congress: "..refers to the variety and variability among living organisms and the eco-logical complexes in which they occur." • The Wildlife Society: "..the variety of life and processes that link plants, animals, soil, air, and water into ecological systems."

  3. Types of Biodiversity: (a matter of scale) • Genetic - each individual organism is unique; a varied genetic base provides a hedge against an unknown future; allows species to adapt through natural selection • Species - each is an important link in the web of life; enhances our survival and adds to stability of individual ecosystems. • Ecosystem - a marsh, a stream, an bottomland forest, an upland forest within a limited geographic area • Landscape - grassland, forest, desert, scattered over a large geographic area

  4. Protecting Biodiversity - what difference does it make? • The field of Conservation Biology deals with this question and ways of preserving diversity • Ecosystem integrity = completeness • Biodiversity = foundation of ecosystems • Eliminating a species damages an ecosystem in ways we probably do not understand.

  5. What is the earths species diversity? About 2 million species identified: - 1.5 million insects - 0.5 million plants - only a few thousand birds and mammals How many not yet identified? - 5 million? 50 million? By preserving ECOSYSTEMS, we can preserve species diversity without knowing what species are present!

  6. Although most species yet to be discovered are bugs, some are not! New genus of rat found in the Andes Mountains in 2000

  7. One-half of world's prescription and non-prescription drugs have active ingredients extracted from wild organisms. • One-fourth of these are from tropical forest plants. • Drug industry is billions of $$ in economy • penicillin = from fungus / tetracycline = from bacteria • anti-biotic from the African Clawed Frog

  8. new birth-control pill from Mexican wild yam

  9. Endangered species of primrose has chemical that may help treat multiple sclerosis • many others known or yet to be discovered

  10. Extinction: a natural process in evolution where certain kinds of animals die out and other better-adapted species take their place • How many species have become extinct? • 99% of all species that ever existed are now extinct! • Fact: all species will eventually become extinct!

  11. What is a SPECIES? • all organisms of the same kind • organisms that freely interbreed • (for sexually-reproducing species) • What is a subspecies?? • What is a population?? • Can look at DNA to find level of similarity • Diversity is the most important point, not whether it deserves a special name from man

  12. Extinct species - species that no longer exists (due to inability to adapt to changes in its environment) • e.g., dinosaurs (why?) • e.g., passenger pigeon (why?) • logging, disease, 1 egg/female, persecution, last one in 1914 • Endangered Species - insufficient #'s left to assure perpetuation of the species (will decline to extinction unless something is changed) • Threatened Species - expect to be endangered

  13. Who decides what species are endangered? • May be international, national or state government, or private organization: • IUCN - International Union for Conservation of Nature: lists about 5,000 species in "Red book" • CITES - Convention on International Trade of Endangered Species (1975): now 120 nations list and protect through treaties endangered (675), threatened, or species of special concern (27,000, mostly plants) due to trade of plants, animals, or their parts. • USDI - U.S. Department of Interior lists over 1,000 species, of which about half are U.S. species

  14. Endangered Species – who decides, cont. • States - many individual U.S. states list species that may be of more-local concern (these species may or may not be on the federal list); Kentucky, no official state list • Private organizations - e.g., over 3,000 plant species in U.S. have been identified as endangered; < 200 are federally protected.

  15. U.S. Laws on Endangered Species • 1966 - Endangered Species Preservation Act • First legislation; called for keeping list, research, and acquisition of habitat • 1969 - Expanded to include some invertebrates • 1973 - Expanded to include all kinds of plants and animals except insect pests • includes "subspecies" (e.g., eastern Mt. lion, N. spotted owl, southern bald eagle) • 1978 - Amended to protect critical habitat

  16. Today the Endangered Species Act: • prohibits killing of listed species • prohibits sale, import/export of whole animal/plant or any part • protects habitat from destruction • No public money can be used to destroy habitat • Exempt: • Little Tennessee River (Tellico) Dam) • snail darter

  17. Also Exempt: • Logging in Pacific Northwest • N. spotted owl, marbled murrelet

  18. CAUSES OF EXTINCTION: • 1. Restricted range or habitat (narrow niche) • Kirtland’s warbler • only exist in an 85X100 mi. Area in Michigan and other isolated sites • “pine barren” habitat of 6-15 year-old trees (5-20 ft. Tall) • about 500 left in the world

  19. 2. Slow population growth rate (low reproduction) • California condor • S 1 egg every 2 years so only about a dozen eggs produced per year in entire world • S researcher dropped an egg ; • 3. Interbreeding with more successful species • red wolf/coyote or black duck/mallard • S “swamping of genes

  20. 4. Non-adaptive behavior • Carolina parakeet • S extinct in 1914 • S flock around dying bird • 5. Specialized diet (narrow niche) • Koala • S eats eucalyptus leaves only • S hunted for fur; can’t hide in eucalyptus forest • S now only in a few protected forests

  21. 6. Pet trade • Puerto Rican Parrot, etc. • S now bred in captivity • 7. Introduction of exotic species • Rats introduced to islands • S kill off many species of birds • S mongoose introduced to kill rats in Puerto Rico ( • S rats nocturnal, mongoose diurnal ;

  22. 8. Open trade • Elephant (ivory) • Alligator (skin) • Tortoise (shell) • Spotted cats (fur) • various birds (plumes) • 9. Pesticides • Peregrine falcon - DDT • Osprey - DDT • Bald eagle - DDT

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