Wednesday, August 15, 2007

Mass Extinctions Explained

We're living in a period of mass extinction that started within the past million years and will last five to thirty more million years. Away went the mastadon and the dodo, the moa and the sabertooth cat, but which species will die out next? It's possible that only 20% of genera will die out, but perhaps 95% will.

Will human beings be part of the survivors? I think so, but maybe the gorillas won't make it. Come back in thirty million years and ask me again.

Most mass extinctions are tied to the wobble of the solar system as we orbit the center of the Milky Way. Due to various gravitational effects, we regularly bob up and down like a horse on a carousel. From one high point to the next high point is approximately 64 million years (+/- 3 million).

As we pass through the galactic plane from the southern side to the northern side, we become subject to more cosmic radiation since the northern side is the "front" of the Milky Way as it travels through intergalactic space. Being on the northern side of the galaxy is like sitting on the front bumper of a pickup truck: you get hit by a lot more bugs than if you're in the bed behind the cab.

It is theorized that those cosmic radiation "bugs" cause bad things (cancer, mutations, clouds, etc.) which cause species to die out.

Some extinctions last only a few million years during the transition from the back of the galaxy to the front, but some last the entire 32 million years the Earth is on the front of the galactic pickup truck.

Right now, we passed through the galactic plane, south to north, within the past three million years. Thus, a mass extinction is beginning. How long it will last, no one knows. But let's get that cure for cancer before it's too late.

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