As far as i know, there is no evidence in the fossil records that indicate any mass extinction during a pole shift. More than likely it will happen when it happens and you won't notice a thing until you happen to look at a compass.

I am searching for a link to a reliable authority to help show the evidence to back up my statement. So untill then this is only an opinion...

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Man can't even create a simple worm, but can create gods by the dozen.

Even Beethoven had his critics..

e=mc2 ( energy=morning coffee x 2)