Biodiversity refers to the variety of species, genetic diversity, and ecosystems on Earth. There are estimated to be 10-15 million species but only 1.4 million have been identified. Major extinction events have occurred throughout history, with the most recent one 65 million years ago wiping out 75% of species including dinosaurs. Today, 20% of vertebrates are threatened with extinction due to human impacts like habitat destruction, invasive species, pollution, overconsumption, and population growth. Island species are especially vulnerable. Conservation efforts aim to preserve biodiversity through protecting endangered species and their habitats.

1. Biodiversity
Geog 100

2. What does it mean?
• Biological diversity…
– Species diversity
– Genetic diversity
– Ecosystem diversity
• About 1.4 million species have been described
by science, est’d. 10 to 15 million on Earth.
• http://tinyurl.com/283be52
• What does “endemic” mean?

3. Species change over time
• Most species that evolve on Earth eventually
become extinct as conditions change
• Scientists have identified at least five major
extinction events over the last 500 million
years or so, the last one about 65 million years
ago when 75% of species became extinct,
including most of the dinosaurs
• Today – a human-caused extinction event?
About 20% of vertebrates are threatened.

4. We are losing biodiversity
• Species extinction due to a variety of human
influences…
• H = Habitat Destruction & Degradation
• I = Introduced and/or Invasive Species
• P = Pollution
• P = Population Growth
• O = Over-consumption

5. Counting the loss
• Famous human-caused extinctions… dodo,
passenger pigeon, many island bird species.
• Some of Africa’s animals are on the brink…
black rhinos, the African wild dog, several
species of frogs & toads, turtles, and fish.

6. Dodo birds

7. Islands
• Island species are especially vulnerable to
extinction.
• Why?

8. Hunting passenger pigeons

9. The last one died in 1914

10. Species Under Stress
• Threatened species – IUCN Red List
• http://www.iucnredlist.org/
• Video
http://www.iucnredlist.org/news/evolution-
lost

11. Why it matters
• Extinction is forever
• "When we try to pick out anything [in nature]
by itself, we find it hitched to everything else
in the Universe.” – John Muir
• Ethical considerations – is destruction
permissible? Especially unnecessary
destruction?

12. 2010 was Intl Year of Biodiversity
• http://www.unep.org/iyb/
• Ilcp video… http://vimeo.com/11499468

13. I=PxAxT
• Impact on ecosystems
• Is a function of all three factors…
– Population
– Affluence (consumption)
– Technology

14. Protection for endangered species
• How can biodiversity be preserved?
• Saving the black rhino…
• http://www.youtube.com/watch?v=ilF0nU_d0
CY&feature=player_embedded#!

15. Biodiversity in RI
• Bioblitz
• http://www.rinhs.org/what-we-do/bioblitz/
• Group research
• Mammals, birds, trees, fish, reptiles &
amphibians, insects
• Bird video
http://www.youtube.com/mjgvideo#p/u/2/0Gyn
sgOJkWg
• Do we have endangered species in RI? Do we
have invasive species?

16. Learn more about biodiversity
• E.O. Wilson
• Umich.edu lesson
http://www.globalchange.umich.edu/globalch
ange2/current/lectures/biodiversity/biodiversi
ty.html
• http://www.biodiversityhotspots.org

17. Next week
• Student reports.