Potentially biogenic carbon preserved in a 4.1 billion-year-old zircon. 2015. PNAS
UCLA geochemists have found evidence that life likely existed on Earth at least 4.1 billion years ago—300 million years earlier than previous research suggested. The discovery indicates that life may have begun shortly after the planet formed 4.54 billion years ago.
The new research suggests that life existed prior to the massive bombardment of the inner solar system that formed the moon's large craters 3.9 billion years ago.
Scientists had long believed the Earth was dry and desolate during that time period. The planet was probably much more like it is today than previously thought.