BOB HIRSHON (host):
The biology of rocks….I’m Bob Hirshon and this is Science Update.
4,300 different kinds of minerals can be found on earth today, far more than the 500 or so that were around when our planet formed billions of years ago. According to Robert Hazen, senior staff scientist at the Carnegie Institution’s Geophysical Laboratory, the cause of the great diversity of minerals we have today was the emergence of life.
ROBERT HAZEN (Carnegie Institution Geophysical Laboratory & George Mason University):
What life does that’s unlike anything else is create new chemical environments, in particular, it pours oxygen into the atmosphere. It’s a gas that just would not occur on earth except for the fact that we have plants, we have microbes, they pump out all the time.
He says the corrosive effects of oxygen led to the formation of several thousand more minerals, such as iron, copper and uranium ores. I’m Bob Hirshon, for AAAS, the science society.