A new theory of life's multiple origins

The history of life on Earth has often been likened to a four-billion-year-old torch relay. One flame, lit at the beginning of the chain, continues to pass on life in the same form all the way down. But what if life is better ...

How 'great' was the great oxygenation event?

Around 2.5 billion years ago, our planet experienced what was possibly the greatest change in its history: According to the geological record, molecular oxygen suddenly went from nonexistent to becoming freely available everywhere. ...

page 2 from 9