CP Environmental Science
2013-2014
Name:___________________________
Unit 2B Notes Packet: Biodiversity
Vocabulary terms are in italics
Chapter 10, Section 1: What is Biodiversity (p.259-262)
I.A World Rich in Biodiversity
Biodiversity- refers to the number of variety of different species in a given area.
A. Unknown Diversity
-The number of known species to science today is around 1.7 million. Most of these species are
insects. Unknown species exist in wildernesses, deep in the oceans, and receive less attention
than large, familiar species.
B. Levels of Diversity
Biodiversity can be studied and described at 3 levels: Species Diversity, Ecosystem Diversity
and Genetic Diversity.
Gene- a piece of DNA that codes for a specific trait that can be inherited by an organism’s
offspring.
II. Benefits of Biodiversity
A. Species are Connected to Ecosystem
Keystone Species- The species that’s critical to the functioning of an ecosystem.
B. Species and Population Survival
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The level of genetic diversity within different populations is very important factor in
species survival because genetic variations increase the chances of survival in given
situations or changes.
C. Medical, Industrial, and Agricultural Uses
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People use different organisms on the Earth for food, clothing, shelter and medicine.
Most of the drugs used in the pharmacy are derived from plants.
CP Environmental Science
2013-2014
D. Ethics, Aesthetics, and Recreation
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Some people believe that we should preserve biodiversity for ethical reasons. People also
value biodiversity for aesthetics or personal enjoyment such as pets, camping or watching
wildlife.
Ecotourism- a form of tourism that supports the conservation and sustainable
development of ecologically unique areas.
Chapter 10, Section 2: Biodiversity at Risk (p.263-269)
I. Current Extinctions
A. Species Prone to Extinction
Endangered Species- species that is likely to become extinct if protective measures are
not taken immediately.
Threatened Species- Is a species that has a declining population and that is likely to
become endangered if it is not protected.
II. How do Humans Cause Extinctions?
A. Habitat Destruction and Fragmentation
-Humans use more and more land to build homes and harvest resources. In this process,
we destroy and fragment the habitats of other species.
B. Invasive Exotic Species
- An exotic species is a species that is not native to a particular region. Exotic species can
threaten the native species
C. Harvesting, Hunting and Poaching
- Excessive hunting and harvesting of species can lead to extinction.
-Poaching- illegal activities such as: hunting, hunting, fishing, harvesting.
D. Pollution
- Humans use chemicals such as pesticides, cleaning agents, drugs, and other chemicals
that end up into food webs around the globe.
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2013-2014
III. Areas of Critical Biodiversity
Endemic Species: species that are native to an area and are found only within that limited area.
A. Tropical Rainforest
-It covers lass then 7% of the Earth’s land surface. Half of the world’s species live in the
tropical rainforest. Many of the species living in these forests have never been described.
B. Coral Reefs and Coastal Ecosystems
-Coral reefs occupy a small fraction of the marine environment however; it contains the
majority of biodiversity. The coral reefs provide the people with food, tourism, coastal protection
and sources of new chemicals. The coral reefs are threatened by human activities (overfishing,
development and pollution).
C. Islands
- When an island rises from the sea, it is colonized by a limited number of species from the
mainland.
D. Biodiversity Hotspots
- The most threatened areas of high species diversity on Earth have been labeled as
biodiversity hotspots. It includes mostly tropical rainforest, coastal areas, and islands.
E. Biodiversity in the United States
- The U.S. includes a wide variety of unique ecosystems: Florida Everglades, California
coastal region, Hawaii, Midwestern prairies and the Pacific Northwest forests.
Case Study: A Genetic Gold Rush in the Rain Forests
Many people see the Amazon Rainforest as a money generating place. Many scientists try to
search for undiscovered species, species that are getting extinct and also for the enlightenment of
the usage of some plants for medicinal purposes (the biotechnical industry). The gene pool in this
rainforest is very large, which allows for the researchers and scientists to discover new drugs and
new ways to improve our existence. Furthermore, in the Amazon Rainforest, there are native
tribes, such as Yanomamo which are connected with the rainforest in a special way. The natives
know many varieties of species in the ecosystem where they live. They use their knowledge of
some plants to combine their chemicals and form complex chemicals used for food, drugs,
weapons and art.
CP Environmental Science
2013-2014
Chapter 10, Section 3: The Future of Biodiversity (p.270-275)
I. Saving Species One at a Time
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When a species is on the verge of extinction, some concern people make efforts to save
the last few individuals.
A. Captive Breeding Programs
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These programs restore the population of a species that are on the verge of extinction by
breeding species in captivity and then reintroduce them to their natural habitats.
B. Preserving Genetic Material
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One way to save the essence of a species is by preserving its genetic material. This is
done by collecting germ plasm (a genetic material collected from reproduction, or germ,
cells from plants or animals.
C. Zoos, Aquariums, Parks, and Gardens
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The original function of the zoos was to put the exotic animals on display. Presently, zoos
help endangered animals to survive and reproduce. In botanical gardens, many plant
species are saved from extinction and these gardens represent a museums of the world’s
biodiversity.
D. More Study Needed
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If we save a few individuals, it will not be enough to preserve a species. Those
individuals rely on inbreeding, which as a result, the gene pool is lowered and if this
species are affected by a disease or different kind of stress, they might die out.
II. Preserving Habitat and Ecosystems
A. Conservation Strategies
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Most conservationists protect the whole ecosystem, compared to just one particular
species. Earth’s biosphere depends on the ecosystems being connected. Some strategies
are to focus on the hot spots, and the other is to identify areas of native habitats that can
be preserved, restored and linked into large networks.
III. Legal Protection for Species
-Many nations have laws to prevent the extinction of species. In the U.S. these laws are the
strongest and most effective.
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2013-2014
A. U.S. Laws
- In 1973, the U.S. Congress passed the Endangered Species Act. This law is designed to
protect plants and animal species that are in danger of extinction.
B. Recovery and Habitat Conservation Plans
- Plans that propose to protect or restore habitat for each species. However, it gets
controversial to stop humans from usage of a particular land.
Habitat Conservation Plan: a plan that attempts to protect one or more species across large
areas of land through trade-offs or cooperative agreements.
IV. International Cooperation
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At the global level, the International Union for the Conservation of Nature and Natural
Resources (IUCN) facilitates efforts to protect species and habitats. The organization has
200 government agencies and 700 private conservation organizations.
A. International Trade and Poaching
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One product of the IUCN has been an international treaty called CITES (the Convention
on International Trade in Endangered Species). The CITES was the first effective effort
to stop the slaughter of African elephants.
B. Biodiversity Treaty
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One of the most ambitious efforts to tackle environmental issues on a worldwide scale
was the United Nations Conference on Environment and Development (the Earth
Summit). Biodiversity Treaty is an international agreement that states to protect the
biodiversity and ensure the sustainable and fair use of genetic resources in all countries.
C. Private Conservation Efforts
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Many private organizations work to protect species worldwide, sometimes more than the
government agencies.
V. Balancing Human Needs
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Attempts to protect species often come into conflict with the interest of the world’s
human inhabitants. The value of a particular species in an ecosystem should be
understood as an important segment of the survival of that species. If we as humans do
not benefit from a species, it doesn’t mean that that particular species does not have a
particular function in its ecosystem.