Biodiversity
Video: Example of Biodiversity (PE)
Biodiversity

Biodiversity means a variety of living organisms
(Bio = Life; Diversity = variety)
Importance of Biodiversity
Case Study

If honey bees die out completely, only wealthy
people would be able to afford things like beef
and ice cream.
Why?
Importance of Biodiversity
Case Study



North America used to have more than 4000
different animals that pollinated plants.
Honeybees were introduced from Europe in the
1800’s and outcompeted other pollinators.
Today, honeybees are declining rapidly and are
one of few animals that act as pollinators
 Decrease in biodiversity = less resilient environment
Importance of Biodiversity
Case Study

The link between honeybees and ice cream…
Pollinates
Is food for
Produces
Importance of Biodiversity
Case Study

What conclusions can we make based on the
honeybee case study?
 The
loss of a single organism has far reaching
consequences
 Species
are all interconnected via food webs and
through other special relationships
 Honey
Bees are a keystone species
 Biodiversity
maintains ecosystems
Levels of Biodiversity
1.
Genetic Diversity
2.
Species Diversity
3.
Ecosystem Diversity
1. Genetic Diversity

The sum of all the genes present in a particular species



Species: Members of a population that look similar and can
breed with each other to produce viable offspring
Each organism within the same species has a different
combination of genes (DNA) which is what makes every
organism unique
This also allows for populations of species to adapt to
changes

E.g. Resistance to disease
How Genetic Diversity Allows
Adaptations

Imagine that a severe drought were to affect the
Savannah and only tall trees could survive. What
would happen if all giraffes were like giraffe “A”
or giraffe “B”?
A
B
C
* The giraffe population would decrease or become extinct
2. Species Diversity


The variety of species in a given area
Having a high variety of species in an ecosystem
allows the environment to survive droughts, plagues,
disease, etc.
2. Species Diversity

E.g. How might this ecosystem manage if a disease
impacted the entire rabbit population?
* The Wild Cat and Jackal would become more dependent on other prey
3. Ecosystem Diversity


A diverse range of habitats, the organisms that live
in those habitats, and the relationships that connect
them.
Any change to a single part of an ecosystem will
have some effect on the entire ecosystem but the
greater the ecosystem diversity to better able it is
to stay balanced
3. Ecosystem Diversity

Genetic and species diversity helps to maintain
ecosystem diversity. (it takes both into account)
In Conclusion


Why worry about biodiversity?
It protects our food supply, maintains ideal
conditions for human life, and ensures resilience
through harsh conditions.
Further Evidence:
Sichuan, a small town in China, controlled pests by spraying pesticides over
their crops. Unfortunately, these pesticides also killed the honeybees. As a
result, humans had to pollinate the pear trees. This takes longer, costs more,
and is much less effective. If we were to do this in Canada it would cost $20
billion in wages and only a fraction of the trees would be pollinated!
Homework

Read pages 31-35
#1-5, 9-10 (p.37)