Japanese researchers think they may have found the earliest evidence of life on Earth on rocks in Canada. In their study in Nature, the scientists from the University of Tokyo say they detected telltale traces of material left behind by decomposing organisms 3.95 billion years ago, reports the CBC. If the findings from northern Labrador hold up, it means that life was kicking around on the planet a mere 500 million years or so after the Earth formed, and perhaps earlier. For perspective, the Atlantic points out that if you thought about Earth's history in a single calendar year, life popped up around the third week of February. Perhaps more remarkable, the study suggests that life formed while the Earth was still being bombarded by asteroids.
"The emerging picture from the ancient-rock record is that life was everywhere," says Vickie Bennett of Australian National University, who wasn't involved in the study. "As far back as the rock record extends—that is, as far back as we can look for direct evidence of early life, we are finding it." There's room for skepticism of the new study, and the Guardian explains the scientific particulars involving carbon isotopes. The upshot is that fellow scientists want more evidence that the graphite detected didn't show up on the rocks much later in the process. Earlier this year, other researchers found what may be even older evidence of life from rocks in the same region, with a range from 3.7 billion to 4.2 billion years ago. One of those researchers tells Gizmodo the new study seems legit based on early data, but "it will take further analyses to provide conclusive evidence.” (Read more discoveries stories.)