1. The Importance of Biodiversity
The need for biodiversity
Vulnerable, Threatened, Extirpated, Endangered, and Extinct species
Keystone species
Species extinction and biodiversity
Natural and human causes of extinction

2. Biodiversity The variety of life in a particular ecosystem.
Measured by counting the number of species in a specific habitat or ecosystem
This measurement is referred to as species richness
What is Biodiversity?

3. Biodiversity
Tropical rainforests have the highest biodiversity of any ecosystem
E.g. The Peruvian rainforest has 283 species of tree in a single hectare while a similar sized forest elsewhere will typically support only species of tree.

4. The Social Value of Biodiversity
The human species depends on biodiversity for its survival
Cleans the air we breathe
Recycles and purifies the water we drink
Absorbs waste we produce
Stabilizes and moderates climate

5. The Economic Value of Biodiversity
Provides enormous economic and community benefits through the use of natural resources for forestry, farming, fishing, recreation, energy

6. At Risk Species Species who are at risk can be classified as:
Vulnerable
Threatened
Extirpated
Endangered
Extinct

7. Vulnerable Any species that is at risk because of declining numbers.
E.g. Grey Fox

8. Threatened
Any species that is likely to become endangered if the factors that make it vulnerable are not reversed
E.g. Peregrine Falcon

9. Extirpated
Any species that no longer exists in one part of a country, but can be found in others
E.g. Grizzly Bear

10. Endangered
A species that is close to extinction in all parts of a country or in a significantly large area.

11. Manatees
Due to boat collisions, entanglement in fishing gear and habitat loss, these gentle creatures have become endangered.
Endangered Species

12. Extinct A species that is not found anywhere Passenger Pigeon
Tasmanian tiger

13. What’s the big deal about the Passenger Pigeon!!!!!

14. Keystone Species
Keystone Species: Species that have strong interactions with other species and affect their health and survival
Keystone Species

15. Example - Bats

16. Bats
Bats are considered pests because they can be a nuances and are scary
and turn into vampires

17. This leads people to kill them and destroy their homes
This leads people to kill them and destroy their homes. However, bats eat moths and pollinate flowers.
So areas that have bats removed now have many fewer flowers and have too many moths which destroy crops.

18. It is very hard to identify important keystone species until after an ecosystem collapses due to their absence
Animals like the passenger pigeon might seem important after they’re gone but there is no way to get them back.

19. The Link between Species Extinction and the Biodiversity of Ecosystems
Extinct refers to a species that has died out and no longer exists on Earth
Although it is a natural process that occurs over thousands and millions of years, human activity has drastically increased the rate of extinction

20. Extinction

21. Natural Causes of Extinction
Competition with other organisms
Environmental disasters
Climate change
Shortage of food
Low reproduction
High number of predators
Competition with invading species

22. Over the course of history there have been many large scale extinctions that are thought to be linked with natural disasters.

23. Human Causes of Extinction
Invasion of habitat
Over hunting
Pollution
Habitat loss and fragmentation
Removing resources
Introducing invading species

24. The Tasmanian Tiger
Despite the name, these animals were stripped marsupials (like kangaroos) not tigers
Native to mainland Australia and Tasmania, they were declared extinct as recently as the 1930s after a century of intensive hunting

25. Human Impact on Extinction
Species extinction have risen significantly with the recent human population explosion over the last 200 years

26. Bill Nye – Biodiversity