Transcript Biodiversity

Biodiversity
Biodiversity

Biodiversity - the number
and variety of species on
Earth.
 number
of known species is
approximately 1.4 million;
most are insects
 estimates of the actual
number of species range
from 10 to 100 million
Loss of Species
Biodiversity is threatened by certain
Biotic Factors:
 Population growth: increased need for
food and space.
 Deforestation: the harvesting of trees for
manufacturing.
 This leads to
HABITAT LOSS.
Loss of Species

The human population is growing so
rapidly and changing the environment so
dramatically, we are causing other species
to become extinct at an increasing rate
Biodiversity is threatened
by certain Biotic Factors:

Poaching - Illegal hunting for valuable
animal products like tusks and tortoise
shells.
Biodiversity is threatened
by certain Biotic Factors:

Invasive Species - species of plants and animals
occurring further than their normal distribution
within an ecosystem.
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They do not have natural predators in the ecosystems
where they are introduced.
Often they can outcompete organisms in the same
niche.
They can also introduce pathogens and diseases that
sicken and kill other animals in the ecosystem.
Invasive Species

Example 1: Cane Toad
 Came
from Hawaii. It was introduced to
Australia to eat cane grubs. The cane toad
did not eat grubs and became a very big
problem!
Invasive Species
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Example 2: Zebra Mussels

Transported from Asia in ship ballast water. Their
populations grew so out of control in some U.S.
waters they clogged pipes of wastewater facilities
creating a major mess and are likely to cause our
native mussels to go extinct.
Invasive Species

Example 3: Phragmites
 Introduced
into the Chesapeake Bay
ecosystem and has crowded out many native
wetland plants.
Biodiversity is threatened
by certain Abiotic Factors:

Pollution - a harmful side-effect of various
activities.
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Eutrophication - when algae blooms kill SAV and
decomposers deplete dissolved oxygen levels in
water.
Bioaccumulation - when toxins become more
concentrated in higher trophic levels.
Temperature - Increasing temperatures due to global
warming can impact the species that live in a delicate
range of temperatures like coral.
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This is known as coral bleaching.
Temperature can also increase the spread of disease.
Loss of Species

Extinction - when the last individual of a species
dies.

habitat destruction is the #1 cause.
Loss of Species
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Most extinctions are occurring in the tropical
rainforest
forests cover approximately 7% of the Earth’s
land surface, but contain approximately 50% of the
world’s species
 rain
Why Save Species?

Biodiversity is one of the major factors of a
healthy and stable ecosystem.
BIODIVERSITY MAINTAINS ECOSYSTEM
STABILITY!!!
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Each species has a role to play in its ecosystem and
each is dependent upon other species for survival
Why Save Species?
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Keystone Species- a species that has a
dominating influence on the composition of a
community
 Examples:
sea otters, beavers
Why Save Species?
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Practical Uses

about 40% of all prescription drugs
are made from living organisms.
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ex. Vinblastine - derived from rosy
periwinkle is used to treat childhood
leukemia.
ex. Taxol - derived from the bark of
the Pacific yew tree is used to treat
cancer.
Plant species not yet discovered
might also provide food or
medicine for the future
Why Save Species?

Personal values
 Extinction
leads to
the loss of objects
of fascination,
wonder, and
beauty.
Efforts to Prevent
Extinctions
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World Wildlife Fund (WWF) - works to protect biodiversity.
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Nature Conservancy - manages a system of nature sanctuaries.
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Friends of the Earth - lobbies governments and gives information to the
public.
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Greenpeace International - stages protests to help stop habitat destruction
and the killing of endangered species.
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International Union for the Conservation of Nature and Natural Resources collaboration of 200 governments and 300 private organizations that
publishes the endangered species list and advises governments on natural
resource management
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Audubon - sponsors research, public awareness. and land acquisition
Future of Biodiversity
Captive Breeding Programs increases threatened or endangered
species populations by breeding animals
under carefully managed circumstances
 Zoos
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and wild animal parks
ex. California condor, Whooping cranes
Future of Biodiversity
Botanical Gardens
 storehouses plant species in hopes of
maintaining genetic diversity.
 lacks space and funds.
Future of Biodiversity
Germ Plasm Banks
 stores the genetic material contained
within the organism for future use.
The Ecosystem Approach
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Concentrates on protecting entire ecosystems
rather than individual species
By concentrating on entire ecosystems, we may
be able to save most of the species in an
ecosystem.
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The health of the entire biosphere depends on the
preservation of individual ecosystems.
The Ecosystem Approach
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To protect biodiversity worldwide,
conservationists suggest that at least 10%
of the earth’s land be set aside as
protected reserves; primarily biodiversity
“hot spots”
The Ecosystem Approach
 Biodiversity
“hot spots” are places in
the world that have many different
species living in one place.