About Earth 35: Manmade Extinction
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Artist Statement: Manmade Extinction
The Holocene period is the sliver of time, 11,700 years so far, when man was present on the earth. There have been five major extinctions of species in past geologic times but none until now has been caused by a single living being. Scientists believe we are in the sixth major extinctions of life and that we are the cause.
This globe commemorates the lost species so far during this Holocene Period. It is a warning of what ignorance and anthropocentric attitudes can inflict on the living species of today.
Here is how our current extinction, while still in progress, compares to the five major extinctions in the 4.5 billion years of the earth (sources include Wikipedia, Britannica Encyclopedia and National Geographic*):
*Ordovician-Silurian extinction about 440 million years ago took the biggest toll on marine organisms when rapid cooling occurred and massive glaciations caused sea levels to drop resulting in a 60-70% extinction of all species. Other causes are postulated such as volcanism, and impact events.
*Late Devonian extinction starting about 375-360 million years ago and lasting 20 million years eliminated 70% of all species. The causes may include asteroid impacts, global anoxia, plate tectonics, sea level changes and climate changes.
*Permian-Triassic Extinction about 250 million years ago was the largest extinction event causing more than 90% of all species to perish. Possible causes are asteroids, comet impacts, or flood volcanism resulting in acid rain.
*Triassic-Jurassic extinction about 200 million years ago resulted in the extinction of 70-75% species on earth. The possible cause is massive floods of lava erupting from the central Atlantic magmatic province, or climate change and rising sea levels resulting from the sudden release of large amounts of C02.
*Cretaceous-Paleogene Extinction about 65 million years ago killed about 75% of species including the dinosaurs. The cause of the extinction is believed by many scientists to be a huge asteroid impact near the Yucatan Peninsula and global warming fueled by volcanic eruptions in India.
*Holocene Extinction, which started 11,700 years ago and continues today have currently ongoing extinctions. It is the first mass extinction caused by a single species, man. In this short period, man has had a huge impact on the earth’s environment. Man has changed the nitrogen cycle by introducing fertilizers, which inadvertently cause dead zones in the ocean. Man has changed the carbon cycle by increasing the C02 in the atmosphere and causing global warming. Man is killing off species of animals for food, ornament, protection, and trophies and by displacing wildlife and cutting off their migration patterns through land use practices. Man has caused pollution of land and water killing many of species and disrupting food chains.
“By the year 2100, human activities such as pollution, land clearing, and overfishing may drive more than half of the world’s marine and land species to extinction.” (Source: www.National Geographic.com).
ARTIST
Ronnie Swire Siegel
Los Angeles, CA, United States
MATERIALS
Stainless steel globe 4-inch diameter covered with paper cut out images of extinct species caused by man during the Holocene Period.