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The Ongoing Holocene Extinction
By Joe Crubaugh

Scientists have concrete evidence that the Earth is currently undergoing the largest mass extinction in 65 million years. Over 50 species are going extinct every single day.

It’s called the Holocene Extinction — Holocene being the current epoch that began at the end of the last ice age, about 10,000 years ago.

From Earth’s fossil record, we know about Six Great Mass Extinctions:

• The Ordovician-Silurian Extinction occurred about 444 million years ago.

  At the time, all complex organisms lived in the sea. The most common theory is that the onset of an ice age caused the extinction, which wiped out over 100 families of marine life. Many trilobite families bit the dust during this event.

• The Late Devonian Extinction happened 364 million years ago.

  This event saw a major worldwide extinction of coral reefs and the marine life they supported, as well as other groups of animals and plants. Nobody’s sure what caused it, but scientists speculate global cooling and several medium-sized asteroid impacts within a few million years of each other may have been the culprits.

• The Permo-Triassic Extinction occurred 251 million years ago.

  The granddaddy of all mass extinctions, this event saw 96% of all marine species and 70% of land vertebrate species kick the evolutionary bucket.

  The die off happened in less than a million years (a very short time in geological terms) and the recovery took 5 million years to crank back up, and another million years after that to get rolling. While not deemed the smoking gun yet, this event coincides with the largest known volcanic eruption in history.

• The Triassic-Jurassic Extinction occurred 200 million years ago.

  Was it caused by climate change, asteroids, or volcanoes? The verdict isn’t clear. What is clear is that 20% of marine life and many large amphibians were wiped out. At least half of all species on the planet bit the dust.

  This event occurred over less than a 10,000 year period, just before the supercontinent of Pangea began to break up.

• The Cretaceous-Tertiary Extinction occurred about 65 million years ago.

  This event was probably caused, or at the least aggravated by, the impact of an asteroid around the size of Manhattan. About 16% of marine families and 18% of land vertebrate families ceased to exist. In North America, over 50% of plant species may have been wiped out.

  And of course…this is the event that doomed the dinosaurs.

• The Holocene Extinction is occurring now.

  Studies of the fossil record show that the normal “background” rate of extinction is about one species every four years. The current rate is between 30,000 and 100,000 per year.

You are now witnessing the fastest of the six great mass extinctions.

And this extinction, without a doubt, is the result of human population growth. By the end of this century, over five million species (half of the species on Earth now) will likely be gone.

“It’s not just species on islands or in rain forests or just birds or big charismatic mammals,” says Stuart Pimm, a conservation biologist researcher from the University of Tennessee. He notes fish, birds, insects, plants, and mammals. “It’s everything and it’s everywhere…it is a worldwide epidemic of extinctions.”

copyright©2007 Joe Crubaugh

Joe Crubaugh is a freelance writer whose psyche is often absorbed with current events, politics, art, culture, society, and the creamy bitterness of a steaming cup of white chocolate mocha. He is the author of numerous personal emails, and on most days he blogs at Hard-boiled Dreams of the World. When he's not writing, Joe spends weekdays masquerading as a software consultant in an undisclosed Southeastern U.S. state.

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