Transcript Slide 1

Threats to Biodiversity
Photo of a forest fragment, surrounded by newly created cattle pasture in Amazonas, Brazil;
Photo of a sign on St. Lucia (provided by John Battista, LSU – taken by one of his former students)
Extinction
?
Current mass extinction
could result in ~ 50% of species
going extinct in 100 years
(Wilson 2002)
Image from Wikipedia
K/T (Cretaceous-Tertiary)
Mass Extinction
~ 65 m.y.a.;
Ended the reign of
the dinosaurs
P/Tr (Permain-Triassic)
Mass Extinction
~ 251 m.y.a.;
~ 96% of all marine species &
~ 70% of all terrestrial species
Extinction
“Martha” – the last
living passenger
pigeon – died on
Sept. 1, 1914 in
captivity in
Cincinnati, OH
Image of Passenger Pigeon (extinct North American bird, once found in Louisiana) from Wikipedia
Extinction
“Not only are species at risk of extinction, but some processes that undergird
ecosystem functions, or that are glorious in and of themselves, are put at risk
from human activities...” Groom et al. (2006, pg. 78)
Image of Dodo (extinct Indian Ocean island bird) from Wikipedia
HIPPO
Habitat destruction
Invasive species
Pollution
Human Population
Overexploitation
E. O. Wilson
(b. 1929)
Photo from Wikipedia; For more information on HIPPO, see: E. O. Wilson (2002) The Future of Life
HIPPO
Habitat Destruction & Degradation
Photos of forest destruction in Brazil & Malaysia
HIPPO
Habitat Destruction & Degradation
“An ever-expanding network of roads, railways, rivers, and shipping lanes
means that only 10 percent of the earth’s surface is now remote, defined as
being at least 48 hours away from a major city. More than half of the world‘s
population lives within an hour of a major city…”
Image from Discover Magazine, Jan-Feb 2010 Special Issue, “Top 100 Stories of 2009” –
“#92: Nowhere to Hide from the Buzz of Civilization
HIPPO
Invasive Species
Kudzu
Snakehead
Walking
catfish
HIPPO
Pollution
“Photoshopped” image of airplanes from www.surfersvillage.com
HIPPO
Pollution
NASA image from May 24, 2010 posted on Wikipedia
HIPPO
Human Population
“More people means more of all the other HIPPO effects” (Wilson, 2002)
12
11
2100
10
9
Old
Stone
7 Age
8
Billions of
People
New Stone Age
Bronze
Age
Iron
Age
6
Modern
Age
Middle
Ages
2000
?
Future
5
4
1975
3
1950
2
1
Black Death —The Plague
1900
1800
1+ million 7000 6000 5000 4000 3000 2000 1000 A.D. A.D. A.D. A.D. A.D. A.D.
years B.C. B.C. B.C. B.C. B.C. B.C. B.C. 1 1000 2000 3000 4000 5000
Image from the Population Reference Bureau © 2006
HIPPO
Overexploitation
Atlantic Cod
Jared Diamond’s “Evil Quartet”
Jared Diamond
(b. 1937)
Habitat destruction &
fragmentation
Introduced species
Overkill
Secondary or cascade effects
Photo from Wikipedia
Compounded Effects & Synergies
Erosion of biodiversity in a site often
results from multiple causes
Curran et al. (1999) Science
Impacts of logging are
exacerbated through
increased frequency of
El Niño events
Image of shrinking forest cover on Borneo from www.planttreesaveplanet.com