earthfire

Global warming, supervolcanoes, asteroid impacts, ice ages, and cosmic radiation sounds like today’s news. But over the millennia, all those things have already changed the Earth. They are both old news and new news.

According to may scientists, our planet had passed through five mass extinctions. The dinosaur extinction was the most recent one. It wasn’t the worst one. The Earth lost about 50 percent of all species by natural disasters 65 million years ago. Go back another 185 million years and there was the one that paleontologists nicknamed the Great Dying. That extinction took 95%of all species on the planet away. It took about 100,000 years  and may have been triggered by megavolcanoes erupting for hundreds of years in Siberia poisoning the atmosphere. Next came ice ages, invasive species, and radiation bombardment from space.

If we are living in a period leading to another mass extinction, it will be the sixth.

I’m not worried about a World War Z against the zombies. But if you follow blogs like IO9 e, you might be thinking about some of the things that Annalee Newitz writes about in Scatter, Adapt, and Remember: How Humans Will Survive a Mass Extinction. It will help you plan what to do after the apocalypse, because you’re not going to stop it.

The name “The Holocene Extinction” is one that has been suggested for the current/next extinction. That covers species that have disappeared and changes since the Holocene epoch starting around 10,000 BC.

I write about the current state of things endangered in the neighborhood of Paradelle but there are plenty of extinctions of  plants and mammals, birds, amphibians, reptiles and arthropods. The best estimates are that almost 900 species extinctions have occurred between 1500 and 2009 (according to the International Union for Conservation of Nature and Natural Resources) but that’s just a very tiny slice of the much bigger pie chart that contains extinctions that are undocumented. That number is staggering because the numbers are more like 140,000 species per year.

Newitz’s book also talks about signs such as the changes happening to bee colonies. Colony Collapse Disorder has been a contemporary mystery.  The usually very organized bees have been getting rather ADD. Worker would fly away, never to return. The teenagers (adolescent bees)  wander the hive without purpose like middle school boys at a dance. Work isn’t done, honey production stops and eggs die of neglect.

The US Department of Agriculture has said that 30% percent of bee colonies have collapsed every winter since 2007. Explanation?  Fungal infections, parasites,pollution? Not sure. But we do know that bee extinction means crop extinction for all those species that rely on their pollination. Did you see that animated Bee Movie? It was funny and yet the moral – not so funny.

When  “sixth extinction” was coined a few decades ago by paleontologist Richard Leakey . He was referring to the current extinction that began about 15,000 years ago in a time of American mammoths, giant elk, sloths, and saber tooth cats,,

But then came the arrival of humans and the megafauna populations collapsed because (according to Leakey) human habitat destruction was to blame for the extinctions. He gives the same explanation for the current amphibian crisis.

Extinctions take hundreds of thousands of years, but the current one is moving at a much faster pace. The current controversy is whether that speed is all based on human activities.

Even if we are not to blame, it’s happening. Maybe the real controversy is whether or not we can slow down or stop the environmental changes any more. We’re in survival mode.

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