Geochemists at UCLA have found what they say is evidence of 4.1 billion-year-old life on Earth.
They analyzed samples of ancient zircon, a gemstone commonly used to make fake diamonds, and found a piece of carbon inside one that had a chemical signature that is associated with photosynthetic life. The results have just been published online by the Proceedings of the National Academy of Sciences.
“Twenty years ago, this would have been heretical; finding evidence of life 3.8 billion years ago was shocking,” said study co-author Mark Harrison told Phys.org.
It’s significant because the Earth itself is only about 4.5 billion years old.
“Life on Earth may have started almost instantaneously,” Harrison said. “With the right ingredients, life seems to form very quickly.”
While humans have given up their conceit that the Earth is the center of the universe, our brains still tend towards thinking that Earth, and life on Earth in particular, is special.
Yet the more we learn, the more we come to see how blissfully unextraordinary we may actually be.
New findings from Mars show that the planet had an ancient hydrological cycle, and wasn’t so different from today’s Earth.
Even that frigid rock Pluto, which we don’t even technically classify as a planet, turns out to have a lot more going on than scientists ever imagined.
And our own planet’s early days? “The early Earth certainly wasn’t a hellish, dry, boiling planet; we see absolutely no evidence for that,” Harrison said. “The planet was probably much more like it is today than previously thought.”
We’re not so special after all. Chances are, there’s life — maybe even intelligent life — out there somewhere. Will we find it, or will it find us?