Biodiversity. Video: Example of Biodiversity (PE)

Post on 31-Dec-2015

234 views 5 download

Tags:

transcript

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”?

* The giraffe population would decrease or become extinct

A B C

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)