Up until now it had been assumed that the alga evolved the capability to source essential nutrients for its survival after it arrived on land by forming a close association with a beneficial fungus called arbuscular mycorrhiza (AM), which still exists today and which helps plant roots obtain nutrients and water from soil in exchange for carbon. The previous discovery of 450 million year old fossilised spores similar to the spores of the AM fungus suggests this fungus would have been present in the environment encountered by the first land plants. Remnants of prehistoric fungus have also been found inside the cells of the oldest plant macro-fossils, reinforcing this idea. However, scientists were not clear how the algal ancestor of land plants could have survived long enough to mediate a quid pro quo arrangement with a fungus. This new finding points to the alga developing this crucial capability while still living in the earth’s waters!