Why preserve biodiversity?
Three class periods (it may be reduced to two periods if students write the essays
• Internet access
• Writing materials
People take different approaches when making the case for preserving biodiversity.
Some argue that biodiversity is important to ensure access to new medications,
while others emphasize the importance of maintaining healthy ecosystems for
recreational purposes such as fishing or camping. Of course, many people use
more than one argument when calling for biodiversity protection. Students will
discuss the importance of maintaining ecosystems and will learn about the various
arguments that people make in favor of preserving the Earth’s biodiversity.
Canada’s public lands are the home of several rare plant and animal species,
so naturally preserving public lands is one the issues on the bio-diversity
- View photos of endangered species on the Internet and discuss the reasons
why these animals are threatened and why they should be protected.
- Use the words “biodiversity”, “ecosystem”, and “extinction” in sentences
to demonstrate their understanding of the words’ meanings.
- Explain why all members of an ecosystem are important.
- List the reasons why biodiversity should be preserved.
- Read Internet articles and take notes on various arguments in favour of preserving
- Write essays in which they explain what they feel are the most compelling
reasons for preserving biodiversity and also describe the arguments they think
would be most likely to convince the general public that biodiversity should
- Acquiring Geographic Information
- Organizing Geographic Information
- Analyzing Geographic Information
Give students approximately ten minutes to browse the list of vanishing species
Then ask them to describe in a class discussion a few of the animals they’ve
learned about and the reasons why these animals are threatened. Ask them to
explain why they think it’s important for these animals to be protected.
Define the following terms, or have students define them: biodiversity, ecosystem,
extinction. To demonstrate their understanding of these terms, ask students to
write or state sentences that use all three of these words. For example, they
might say, “In order to preserve biodiversity and prevent species extinction,
all members of an ecosystem must be protected.”
Ask students to explain why all the members of an ecosystem are important. What
happens if one member of an ecosystem no longer exists? For example, what might
happen if a certain type of fish dies out of a lake ecosystem, leaving its predators
without a food source and its prey without a predator? Discuss potential impacts
for animal and plant members of the ecosystem and for people who live near or
make use of the ecosystem (e.g. fishers or tourists).
Divide the class into groups of about three students each. Ask the groups to
discuss and list the reasons why they think biodiversity is important and why
endangered animals and habitats should be protected. Why should ecosystems be
kept healthy, with every member of the ecosystem protected? Groups should list
all their ideas.
Discuss the groups’ ideas with the class. Inform students that, as they may
have already realized from making their lists, there is more than one argument
in favor of preserving biodiversity and maintaining healthy ecosystems. Five
major arguments are:
Economic (“Biodiversity can help people make money or
keep people from losing money”);
Recreational (“People love outdoor activities like fishing
and backpacking, which would not be possible if ecosystems were destroyed”);
Human health (“Biodiversity can help people find better
cures for illnesses”);
Human rights (“If biodiversity is protected, indigenous
people can continue to live in their native lands”); and
Spiritual/intrinsic value (“Biodiversity should be preserved
for its own sake; animals and plants have a right to live; people rely on wild
places and creatures for spiritual fulfillment”).
Ask students if they’ve identified any of these types of arguments in
their lists. Tell them that many people who believe biodiversity should be preserved
will use more than one of these arguments to make his or her point. For example,
a person may believe that every species has an intrinsic right to live but may
also be excited about prospects for finding new medications from the Earth’s
plant and animal species.
Have the students visit the following Web sites to read some of the arguments
in favour of preserving biodiversity. For each site they visit, ask them to write “economic,” “recreational,” “human
health,” “human rights,” and “spiritual” to indicate
which argument, or arguments, the site makes in favour of preserving biodiversity.
Can We Do?
After students have looked at the above Web sites, ask them to write one to
three sentences for each of the five types of arguments. Their sentences should
provide specific examples of these pro-biodiversity arguments.
Suggested Student Assessment
Have each student write a two-paragraph essay about preserving biodiversity.
The first paragraph should explain which arguments they found the most compelling
and why. The second paragraph should explain which of the arguments they read
about on the Internet seems the most likely to convince people that biodiversity
should be preserved. You can pose the following questions as guidelines for writing
- Paragraph 1: You’ve learned about several different reasons why
people believe biodiversity should be preserved. Which of these reasons do
you find the most convincing, and why? Choose one or two.
- Paragraph 2: Which of the reasons for preserving biodiversity do
you think would be the most likely to convince people that biodiversity should
be preserved? Why?
Extending the Lesson
Have students write letters to the director of the World Wildlife Fund or another
conservation organization in which they recommend the angle they think that organization
should take when trying to convince the public to support biodiversity protection.
Which of the five pro-biodiversity arguments do they think would be the most
productive and convincing, and why? They can suggest that the organization use
all five arguments, just one, or a few.
Have students search the Internet or print materials to find examples of conservation
programs. Ask each student to choose one program. Ask the students to write paragraphs
explaining how the success of this program would help address the economic, recreational,
human health, human rights, and spiritual/intrinsic value arguments in favor
of biodiversity. For example, how might the success of this conservation program
help indigenous people?
Why preserve biodiversity? (Adobe PDF document)