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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
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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.

Dec 25, 2015

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Cecily Wilson
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Page 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.

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

Page 2: 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.

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."

Page 3: 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.

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

Page 4: 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.

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.

Page 5: 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.

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!

Page 6: 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.

Although most species yet to be discovered are bugs, some are not!

New genus of rat found in the Andes Mountains in 2000

Page 7: 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.

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

Page 8: 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.

• new birth-control pill from Mexican wild yam

Page 10: 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.

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!

Page 11: 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.

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

Page 12: 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.

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

Page 13: 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.

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

Page 14: 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.

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.

Page 15: 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.

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

Page 16: 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.

• 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

Page 17: 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.

Also Exempt:

Logging in Pacific Northwest

N. spotted owl, marbled murrelet

Page 18: 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.

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

Page 19: 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.

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

Page 20: 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.

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

Page 21: 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.

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

Page 22: 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.

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

Page 23: 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.