Lesson 1
Biodiversity
JISHA JOSEPH
Learning Outcomes for this Lesson:
 Describe how ecological processes rely on the biological
diversity of the community.
 Given a specific biome, describe the ecological services that
are if benefit humans.
Focus Question
Why is biodiversity important?
New Vocabulary
EXTINCTION
BIODIVERSITY
GENETIC DIVERSITY
SPECIES DIVERSITY
ECOSYSTEM DIVERSITY
GENE: functional unit that controls the expression of inherited
traits and is passed from generation to generation
Endangered Species
How is Extinction
different from
Endangered?
 An endangered species likely will become
extinct without conservation efforts.
What is Biodiversity?
 When an entire species permanently
disappear from the biosphere, it is called
EXTINCTION.
 As species become extinct, the variety of
species in the biosphere decreases, which
decreases the health of the biosphere.
 BIODIVERSITY is the variety of life in an
area that is determined by the number of
different species in that area.
 Biodiversity is increased by the formation
of new species and decreased by the loss
of species (extinction).
 There are three types of biodiversity to
consider:
1. Genetic Diversity,
2. Species Diversity
3. Ecosystem Diversity.
Types Of Biodiversity – 1. Genetic Diversity

The variety of genes or inheritable
characteristics that are present in a
population comprises its genetic diversity.

The variety of colours in the beetles
demonstrates a form of genetic diversity.

The beetles have other characteristics that
differ such as resistance to a particular
disease, the ability to recover from a
disease, or the ability to obtain nutrients for
survival.

The beetles with these characteristics are
more likely to survive and reproduce than
beetles without these characteristics.

Genetic diversity within interbreeding
populations increases the chances that some
individuals will survive during changing
environmental conditions or during an
outbreak of disease.
Types Of Biodiversity - 2. Species Diversity

The number of different
species and the relative
abundance of each in a
biological community is called
species diversity.

The species composition of
one community can be
completely different from
that of another community.

As you move geographically
from the polar regions to the
equator, species diversity
increases.

Saving an entire community
can save many species,
whereas disrupting a
community threatens the
existence of all species.
Types Of Biodiversity - 3. Ecosystem Diversity
 The variety of ecosystems
present in the biosphere is called
ecosystem diversity.
 An ecosystem is made up of
interacting populations and the
abiotic factors that support them
such as water, temperature,
oxygen , sunlight etc leading to
stable ecosystem.
 Different locations around the
world have different abiotic
factors that support different
types of life.
 Most of the ecosystems on Earth
support a diverse collection of
organisms.
The Importance of Biodiversity
DIRECT VALUE
Medicinal Value
Agricultural Value
Consumptive Use Value
INDIRECT VALUE
Biogeochemical Cycles
Waste Recycling
Provision of Fresh Water
Prevention of Soil Erosion
Regulation of Climate
Ecotourism
The Importance of Biodiversity - Direct Economic Value
 Maintaining biodiversity has a direct
economic value to humans.
 Humans depend on plants and
animals for food, clothing, energy,
and medicine.
 Most of the world’s food crops come
from just a few species.
 Wild species serve as reservoirs of
desirable genetic traits that might be
needed to improve commercial crop
species.
 Using genetic engineering, crops
have been produced that are
resistant to some insects, that have
increased nutritional value, and that
are more resistant to spoilage.
 The distant relative of corn, teosinte is resistant
to the viral diseases that damage commercial
corn crops. Using this wild species, plant
pathologists developed disease-resistant corn
varieties.
 If this wild species had not been available, this
genetic diversity would have been lost, and the
ability to develop disease-resistant corn varieties
would also have been lost.
 Many of the medicines that are
used today are derived from plants
or other organisms.
Willow Tree
 Penicillin, a powerful antibiotic
discovered in 1928 by Alexander
Fleming, is derived from bread mold
 Ancient Greeks, Native Americans,
and others extracted salicin, a
painkiller, from the willow tree.
Today, a version of this drug is
synthesized in laboratories and is
known as aspirin.
 Madagascar periwinkle flower, is
used to prepare an extract that is
useful in treating some forms of
leukemia (Blood Cancer). This
increased the survival rate for some
leukemia patients from 20 percent
to more than 95 percent.
Madagascar Periwinkle Flower
The Importance of Biodiversity - Indirect Economic Value
 A healthy biosphere provides many services to
humans and other organisms that live on Earth.
For example,
1. Green plants provide oxygen to the
atmosphere and remove carbon dioxide.
2. Natural processes provide drinking water that
is safe for human use.
3. Substances are cycled through living organisms
and non-living processes, providing nutrients
for all living organisms.
4. Healthy ecosystems provide protection against
floods and drought, generate and preserve
fertile soils, detoxify and decompose wastes.
5. Regulate local climates.
 When healthy ecosystems are preserved, the
services the ecosystems provide will continue
to be less expensive than performing the same
services with technology.
The Importance of Biodiversity - Aesthetic & Scientific Values
 Biodiversity and healthy
ecosystems have
aesthetic and scientific
values.
Lake Tahoe , California
 Sustaining biodiversity
helps humanity by
preserving landscapes of
recreational or
inspirational value.
 There is value in
maintaining healthy
ecosystems that are
beautiful or interesting
to study.
 It is difficult to assign
economic value to these
services.
Urbanization, increased runoff, and other forms of pollution have
harmed the environment’s health. Invasive species such as clams,
pond weed, and even domestic goldfish have also upset the lake’s
ecosystem.
Quiz
1. In which location would you expect to find the greatest
species diversity?
A
Canada
B
Costa Rica
C
Mexico
D
United States
CORRECT
Quiz
2. Suppose there is a litter of five rabbit kits. Each kit is a
different color and has different markings. Which term
best describes the litter?
A
ecosystem diversity
C
genetic diversity
CORRECT
B
species richness
D
species diversity
Quiz
3. Which represents an indirect value of biodiversity?
A
food
B
flood protection
C
clothing
D
medicines
CORRECT
Quiz
4. Which term best describes this collection of locations:
a forest, a freshwater lake, an estuary, and a prairie?
A
genetic diversity
B
extinction
C
ecosystem diversity
D
species diversity
CORRECT