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Earth’s continental crust may have emerged 500 million years earlier than scientists had previously estimated. Pinning down when our planet’s land emerged could help us understand the conditions in which primitivevegetationprimatespatial primitive life began. Today, new oceanic crust rises at mid-ocean ridges where tectonic plates drift apart. Continental crust is usually much older, formed from volcanism where plates crash into each other, everlastinginfestingharvestingthrusting thrusting a thicker, less-dense layer above sea level. Weathering of continental crust adds evidencewastenutrientsorients nutrients to the ocean, a process that may have played a role in supporting primordial life. The big question is: when did continental crusts start forming? To try to answer that, Desiree Roerdink at the University of Bergen in Norway and her colleagues analysed 30 ancient rock samples from six sites in Australia, South Africa and India. These contained barite, which can form in hydrothermal vents – fissures in the ocean floor whichwherewhywhat where warm, mineral-rich waters react with seawater.