In a piece of zircon from Jack Hills, Western Australia, scientists discovered traces of graphite - pure carbon. According to the research, the carbon has a characteristic signature, a specific ratio of carbon-12 to carbon-13, that indicates the presence of photosynthetic life. As the zircon is 4.1 billion years old, based on its ratio of uranium to lead, this may be the earliest evidence of life on Earth. The clip includes X-ray microscopy of the zircon and reconstruction of the image slices from the X-ray microscopy.
Credit:
Stanford/UCLA
Potentially biogenic carbon preserved in a 4.1 billion-year-old zircon
Elizabeth A. Bella, Patrick Boehnkea, T. Mark Harrisona, and Wendy L. Maob
PNAS DOI: 10.1073/pnas.1517557112
