A MOUNTAINEER TAKES A WELL-NEEDED BREATH OF OXYGEN FROM HIS MASK NEAR THE TOP OF MOUNT EVEREST. SOURCE: http://ucrtoday.ucr.edu/3827/oh-oxygen

One of the most important things that makes Earth special is the abundant oxygen in its atmosphere. How it got that way is a surprisingly complicated story that’s just coming to light. It’s a story I delve into for this week’s “Matter” column in the New York Times. Check it out.

 

Originally published October 4, 2013. Copyright 2013 Carl Zimmer.