4.1 Billion-Year-Old Fossil Suggests Life On Earth Started Much Earlier

WASHINGTON (CBS/AP) -- Scientists have found fossil-like hints that some kind of life existed on Earth 4.1 billion years ago -- when the planet was a mere toddler.

That's 300 million years earlier than previously thought.

It changes the way scientists thought Earth was like soon after it formed 4.5 billion years ago. And it also gives them reason to theorize that life itself is more plentiful throughout the universe.

Researchers examined grains of the mineral zircon from western Australia's Jack Hills and dated them to when Earth was barely 400 million years old. Inside one they found carbon residue that they suggest is a remnant of a colony of tiny organisms of some unknown type.

Their report was published Monday in the journal Proceedings of the National Academy of Science.