The Value of Biodiversity and the Trouble with Invasive Species
Created for SPICE by Christine Stracey and La Monica Malone
March 2005
Biodiversity, Oh Phooey!
Lesson 2
Key Question(s): Why is biodiversity important? Where do humans fit into
biodiversity?
Science Subject: Biology and Integrated Science
Grade Level: 6th – 8th grades
Science Concepts: Biodiversity, human impact on environment, processes of
life, and how living things interact with their environment.
Overall Time Estimate: 50 minutes
Learning Styles: Visual, auditory, and kinesthetic
Vocabulary:
 Biodiversity- the variety of living organisms considered at all levels, from
genetics through species, to higher taxonomic levels and including the
variety of habitats and ecosystems.
 Ecosystem- a community of organisms and their interrelated physical and
chemical environment
 Species- a group of interbreeding populations that are isolated from
other such groups.
Lesson Summary: In an ecosystem there are hundreds of species of animals
and plants co-existing. In this activity the students will answer questions
from Bill Nye Biodiversity video. Afterwards, the students will discuss their
answers to the questions in small groups and then as a class.
Student Learning Objectives:
The student will be able to:
1. define biodiversity
2. explain what role humans play in the ecosystem
3. explain what a person can do to help promote biodiversity
Materials:
Per classroom:
TV and VCR
Bill Nye Biodiversity video
Per student:
Biodiversity worksheet (created by Sylvia Brooks)
Background Information:
The natural world is very different today than it was 10,000 or even 1,000
years ago. Every natural ecosystem on the globe has been altered, many
severely, as a consequence of the rapid increase in human population size and
expansion of human habitation. However, the problem is not just a
consequence of the number people on the earth but is also a product of
where and how they live. For example, the wealthy industrialized world
consumes a disproportionate share of the global resources, while
commercialized agriculture and forestry in developing countries has
displaced rural inhabitants onto hillside slums or into other ecologically
fragile areas. The ultimate consequence is a loss in biodiversity. In fact,
annual species extinction is estimated to be somewhere between 20 and 30
thousand per year, or between 50 and 80 per day. Based on these
estimates, more than 25% of the earth’s life forms could be lost in the next
century most before they are even discovered and named by scientists.
Who Cares?
Why should we care about biodiversity? Scientists often treat the
value of biodiversity as a given, however it may not be as obvious to young
students or to the general public at large. This is problematic because
efforts to conserve biodiversity require broad public support. Having an
informed and scientifically literate populous that has a conceptual
understanding of the value of biodiversity is critical to the maintenance of
the earth’s resources for generations to come. Customarily, the value of
biodiversity has been separated into two main types: “Utilitarian” or
“Intrinsic”.
Utilitarian Values
Utilitarian value refers to the value something has as a means to
another’s end. Using this categorization, biodiversity can be split into three
basic forms; goods, services, and information. Humans eat, heat with, build
with, make medicines from, and consume many living things. However, we
have only explored a small fraction of the life on earth for their potential
use to us. Many foods, medicines, materials may still await discovery and
many may already have gone extinct.
Biodiversity is also an important provider of services. For example,
plants replenish the earth’s atmosphere with oxygen and remove carbon
dioxide. Insects, birds and bats are important pollinators of wild plants and
important domesticated agricultural species of plants. Many fungi, microbes,
insects, birds and other scavengers help decompose and clean up dead
organic material. Currently, only about 20% of earth’s 10-20 million species
are known to science.
The loss of species unknown and unexplored has been compared to
setting fire to a vast library and burning books that no one has even read.
Each species may be comparable to a medical text, agricultural guide,
orconstruction manual, each lost with the fire. This information can be
considered a potential economic good that should be conserved. A quote
from Meadows (cited in Meffe and Carrol 1994) captures this value:
“Biodiversity contains the accumulated wisdom of nature and the
key to its future. If you ever wanted to destroy a society, you
would burn its libraries and kill its intellectuals. You would destroy
its knowledge. Nature’s knowledge is contained in the DNA within
living cells. The variety of genetic information is the driving engine
of evolution, the immune system of life, the source of
adaptability.”
Intrinsic Value
Some have argued that intrinsic value exists objectively in living
things because organisms are self organizing and self directed. In other
words, organisms have their own goals and purposes. These goals and
purposes may be either consciously chosen as in some higher more sentient
beings or may be unconscious genetically determined goals. In whatever
form, the goals of all living things include growing to maturity and
reproducing. Machines, which may be said to have no intrinsic value (only
subjective value), differ from living beings in that they have no self
interests. They have no built in goals only the goals imposed by a human.
Despite the apparent enormity of the problem of conserving
biodiversity there are reasons to be optimistic and solutions that work; the
most effective of which is making people informed that all species have the
right to exist, and that we all depend on each other in some form.
Advance Preparation: Make worksheet copies for each student
Procedure:
1. Ask the students if they can tell you the definition for the word
species.
2. Give the students the definition.
3. State to the students that today’s lesson is about biodiversity and
how humans can impact an ecosystem.
4. Handout question sheet.
5. State to the students that the question sheet goes along with the
video and they are to answer the questions as the video is playing.
6. Play the video.
7. Divide the students into groups of 3-5. Have them discuss their
answers to the questions. You should walk around and correct any
wrong answers and mediate when necessary.
8. After the discussions have the students discuss the positive and
negative consequences of human actions on the Earth’s system.
Resources/References:
Meffe, G. K. and C. R. Carroll. 1994. Principles of Conservation Biology.
Sinauer and Associates Inc..
Gibbons, W. 1993. Keeping all the Pieces: Perspectives on natural history
and the environment. Smitsonian Institution Press.
Wilson. E. O. 1984. Biophilia. Harvard University Press.
Bill Nye the Science Guy – Biodiversity Enhanced Classroom Edition.
Available from:
http://dep.disney.go.educational/store
Sunshine State Standards:
SC.D.1.3.2, SC.D.2.3.2, SC.G.2.3.2, and SC.G.2.3.4
Provided by
Name: ________________
Biodiversity
Bill Nye the Science Guy Video
1) Where do most of the world’s living things live? [oceans]
2) What is biodiversity? [different kinds of life]
3) Where do people fit in? [everywhere]
4) Are the things in an ecosystem connected together or separate?
[connected]
5) What is an ecosystem? [place where plants and animals live]
6) What is the largest ecosystem? [water]
7) Name one thing you can do to help promote biodiversity. [recycle,
leave nature in nature, plant a tree, stay on trails, don’t dump]
8) How many species are there in the world? [30 million]
9) How many species are we losing every hour? [17]
10)
Why is biodiversity important? [we don’t know which species are
important to us]
Name: ________________
Biodiversity
Bill Nye the Science Guy Video
11) Where do most of the world’s living things live? [oceans]
12)
What is biodiversity? [different kinds of life]
13)
Where do people fit in? [everywhere]
14)
Are the things in an ecosystem connected together or separate?
[connected]
15)
What is an ecosystem? [place where plants and animals live]
16)
What is the largest ecosystem? [water]
17)
Name one thing you can do to help promote biodiversity.
[recycle, leave nature in nature, plant a tree, stay on trails, don’t
dump]
18)
How many species are there in the world? [30 million]
19)
How many species are we losing every hour? [17]
20) Why is biodiversity important? [we don’t know which species are
important to us]