Download Chapter 10: Biodiversity p. 240-258

Chapter 10: Biodiversity
p. 240-258
1. What is biodiversity?
2. Biodiversity at Risk
3. The future of Biodiversity
Key Terms
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Biodiversity
Gene
Keystone species
Ecotourism
Endangered species
Threatened species
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Exotic species
Poaching
Endemic species
Germ plasm
Endangered species act
Habitat conservation
plan
• Biodiversity treaty
objectives
• Describe the diversity of species types on Earth,
relating the difference between know numbers
and estimated numbers.
• List and describe 3 levels of biodiversity.
• Explain 4 ways in which biodiversity is important
(benefits) to ecosystems and humans.
• What are some medical examples?
• Analyze the potential value of a single species.
(Keystone) Give an example.
What is biodiversity?- Biological
Diversity(number and variety of
species in an area)
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What causes species to become extinct?
How many species are becoming extinct?
How much extinction is natural?
Do you think humans should try to prevent the
loss of species?
 If we study other organisms and preserve
biodiversity helps us for our own survival.
Unknown Diversity•
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Haven’t discovered yet
Deep in ocean, remote wilderness
Know more about trees and animals
Less about insects and fungi
Levels of Diversity
1. Species diversity- all the differences between
populations of species, as well as between
different species
2. Ecosystem diversity- variety of habitats,
communities and ecological processes within
and between ecosystems
3. Genetic diversity- different genes contained
within all members of a population
Benefits of Biodiversity
1. Impact the stability of ecosystems and
populations
2. Healthy ecosystems to ensure healthy
biosphere
3. Increase in genetic diversity (no
bottlenecking)
4. Medical and Agricultural
5. Ethics, Aesthetics and Recreation
(ecotourism)
Keystone Species
Sometimes changes in the population of a single species, often called a
keystone species, can cause dramatic changes in the structure of a
community.
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In the cold waters off the Pacific coast of North America, for example, sea
otters devour large quantities of sea urchins.
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Urchins are herbivores whose favorite food is kelp, giant algae that grow in
undersea “forests.”
– A century ago, sea otters were nearly eliminated by hunting. Unexpectedly, the
kelp forest nearly vanished.
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Without otters as predators, the sea urchin population skyrocketed, and
armies of urchins devoured kelp down to bare rock.
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Without kelp to provide habitat, many other animals, including seabirds,
disappeared.
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Otters were a keystone species in this community.
Ecology 2010
Biodiversity at risk- objectives
• Define and give examples of endangered and threatened species.
• Describe several ways that species are being threatened with
extinction globally. What are the humans doing?
• What are exotic species? Give an example.
• Explain poaching? How does this affect the biodiversity?
• Explain which types of threats are having the largest impact on
biodiversity.
• List areas of the world that have high levels of biodiversity and
many threats to species.
• What are endemic species? Give an example.
• Compare the amount of biodiversity in the US to that of the rest of
the world.
Current Extinctions
• Past: Most extinctions are mass due to climate
change (natural)
• Current: Between 1800 and 2100 25% of all
species on earth may become extinct due
to humans (not natural)
Species prone to extinction- small populations
in limited areas, small gene pool, migrate,
need large or special habitats, exploited by
humans
Species prone to extinction• Endangered species- likely to happen if
protective measures are not taken
immediately
• Threatened species- has declining
population and that is likely to become
endangered if it is not protected
Human Impact?
Population growth accelerated and so has rate
of extinctions (table 3 p. 246)
1. Destruction of habitats and fragmentation
2. the introduction of nonnative species
(Invasive Exotic species)
3. Harvesting, hunting, and poaching
4. Pollution
Human Impact?
1. Destruction of habitats and
fragmentation
- Almost 75% of extinctions now occurring
- 2001 Florida Panther 80 left
Human Impact?
2. the introduction of nonnative species
-Invasive Exotic species – species that is not
native to a particular region
Can threaten native species have no natural
defenses against them
Hawaii strict rules of brining in plants and fruits
-(fire ants, zebra muscles, many plants)
Human Impact?
3. Harvesting, hunting, and poaching
- 1800s- to 1900s 2 billion passenger pigeons
were hunted to extinction and bison was
hunted nearly to extinction
- Pets, house plants, wood ,food, medicine
- New laws to regulate hunting, fishing,
harvesting, trade
- Poaching- illegal trade of regulated wildlife
Human Impact?
4. PollutionPesticides, cleaning agents, drugs are making
their way into food webs
- DDT and bald eagle only illegal to use in us
Areas of Critical Biodiversity
Endemic species- are native to and found only
within a limited area
1. Tropical rain Forest
2. Coral Reefs and Coastal Ecosystems
3. Island-
Tropical Rain Forest
• Covers less than 7% of earths land surface
• However over half of world’s species live in
these forest
• Many have never been identified or described
• Unknown numbers of species are
disappearing as tropical forests are cleared for
farming
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http://library.thinkquest.org/11353/trforest.htm
Coral Reefs and Coastal
Ecosystems
• Also occupy a small fraction of marine
environments yet contain the majority of the
biodiversity
• Food, tourism revenue, coastal protection,
new chemicals
• 1998 study estimated $375 billion per year
• 60% reefs threatened by human activities
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Island
• Colonized by a limited number of species from
mainland (Galapagos and Hawaiian Islands)
• Holds very distinct but limited set of species
• Hawaii hold 28 species of birds called
honeycreepers
Biodiversity Hotspots
• Most threatened areas of high species
diversity
• 25 areas- many have lost at least 70% of
original natural vegetation
• Madagascar- 18% forest remains, more than
10,000 flowering plant species are endemic
91% of 300 reptile
33 species of lemur
Biodiversity in US
1. Florida Everglades
2. California coastal region
3. Hawaii
US holds high numbers of species of freshwater
fish, mussels, snails, crayfish, pine trees and
sunflowers
California Floristic Province- 3,488 native plants
(2,124 are endemic and 565 threatened or
endangered) threatened by local human growth
10.3 objectives
• List and describe 4 types of efforts to save
individual species.
• Explain the advantages of protecting entire
ecosystems rather than individual species.
• Discuss ways in which efforts to protect
endangered species can lead to controversy.
• Describe 3 examples of worldwide cooperative
effort to prevent extinctions.
• Explain the outcomes of CITES and Biodiversity
Treaty.
Future of Biodiversity
Slowing the loss of species is possible, but to do
so we must develop new approaches to
conservation and sensitivity to human needs
around the globe.
Saving on Species One at a Time
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Captive- Breading Programs
Preserving genetic material
Zoos, aquariums, parks and gardens
More study needed
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http://www.thehindu.com/sci-tech/energy-andenvironment/article3568516.ece
Captive-Breeding Programs
• Breeding species in captive in hopes to restore
populations
• California Condor- Scavengers, habitat loss,
poaching, led poisoning
• 1986- 9 remaining left as of 2002 58 condors
returned to wild and 102 still live in captivity
• But will they reproduce in the wild to restore
their populations
Preserving Genetic Material
• Germ Plasm- any form of genetic material that
can reproduce to produce new life
Seeds, sperm, eggs or DNA
• Germ-Plasm banks- store for future use of
research
Zoos, Aquariums, Parks and
Gardens
• Original was to put exotic animals on display
• Now house few remaining organisms
• Botanical gardens house about 90,000 species
of plants worldwide
More study needed
• Saving a few individuals does little to preserve
a species
• Captive species may not reproduce or survive
again in the wild (Lonesome George)
• Vulnerable to infectious disease and genetic
disorders caused by inbreeding
• Last resort to save species
Preserving Habitats and
Ecosystems
• Number one way to save species is to protect
their habitats
• More than just a small plot of land
1. Conservation Strategies- protect the
ecosystems rather than the individual species
Main focus is on world hot spots
More study is needed for preservation
Legal Protection
• US Laws– 1973 US Congress passed Endangered Species Act
(p255 table 4) protect plant ad animal species in
danger of extinction
– USFWS must compile a list
– May not be caught or killed, not uprooted, sold or
traded
– No project can jeopardizes endangered species
– Must prepare a species recovery plan for each
Recovery and Habitat
Conservation Plan
• Can be controversial for human use
• Habitat conservation plan- attempts to protect
one or more species across large area of land
through trade-offs or cooperative agreements
International Cooperation
• International Union for the Conservation of
Nature and Natural Resources (ICCN)- try to
protect species and habitats
• 200 governmental agencies and over 700 private
conservation organizations
• Red List of species in danger ww
• Advised governments on ways to manage natural
resources and work with groups life World
Wildlife Fund to sponsor conservation projects
International Trade
and Poaching
• CITES- Convention on International Trade in
Endangered Species
• Fist effective effort to stop the slaughter of
African elephants (poaching for Ivory)
• Biodiversity Treaty- Earth Summit- 100 world
leaders 30,000 other participants met in 1992 in
Rio de Janeiro, Brazil- Treaty goal was to preserve
biodiversity and ensure that sustainable and fair
use of genetic resources in all countries
Private efforts• World Wildlife Fund
• Nature Conservancy
• Greenpeace
Balancing Human Needs
Attempts to protect species often come into conflict
with the interest of the world’s human
inhabitants. Sometimes, an endangered species
represents a source of food or income, in other
cases, a given species may not seem valuable to
those who do not understand the species role in
an ecosystem
Many conservationists feel that an important part
of protecting species making the value of
biodiversity understood by more people.