Tracking Down the First Oxygen Users 109
sciencehabit writes "None of us would be here today if, billions of years ago, a tiny, single-celled organism hadn't started using oxygen to make a living. Researchers don't know exactly when this happened, or why, but a team of scientists has come closer than ever before to finding out. They've identified the earliest known example of aerobic metabolism, the process of using oxygen as fuel. The discovery may even provide clues as to where the oxygen came from in the first place."
Re:Oxidizer, not fuel (Score:4, Interesting)
In a hydrocarbon atmosphere, you can burn oxygen. All our definitions are oriented around our oxygen-based atmosphere. I'm sure we'd call oxygen 'fuel' if we lived in a hydrocarbon atmosphere and oxygen was the scarcer material.
Which made a wonderful plot for Isaac Asimov's lovable The Dust of Death [wikipedia.org] :) You can tell the guy was a chemist. ;-)
At some levels... (Score:5, Interesting)
... the human race shares certain critical traits with these little guys.
Like them, we're creating a cataclysmic event in the biosphere that will probably wipe ourselves out, but allow the next generation of life to thrive.
Unlike them, we out to be able to mitigate the impact of our presence, but while we're smart enough to see what we are doing, we don't have the fortitude to change our ways.
Re:Where the oxygen came from... (Score:3, Interesting)
"My understanding ... is that atmospheric oxygen at levels high enough to sustain oxygen based metabolism came from plants and trees"
Your understanding is quite wrong.
By the time there were "plants and trees" the major part of the biosphere already was oxigen dependant.
The change of the atmosphere from reductive to oxidative predates trees by about two billion years -the start of the proterozoic age is marked about 2.4 billion years ago (with a strong spike around the precambric which still predates trees by about 300 million years).
It's my understanding that cyanobacteria [wikipedia.org] is responsible for initially creating earths oxygen. I can't say I know much about the historical aspect of it. But I used to keep saltwater reef/fish tanks, and it can become a big problem if you do something wrong. It's really nasty slimy algae looking stuff. I used to find in ironic how much many fish keepers despised the stuff, and yet we probably wouldn't be here without it.
Re:Oxidizer, not fuel (Score:5, Interesting)