Earth 4.4 billion years ago was flat and almost entirely covered in water with just a few small islands, new research suggests. Scientists came to the conclusion after analysing tiny zircon mineral grains from a region of Western Australia containing the oldest rocks ever found. “The history of the Earth is like a book with its first chapter ripped out with no surviving rocks from the very early period, but we’ve used these trace elements of zircon to build a profile of the world at that time,” says lead researcher Antony Burnham, from the Australian National University. “Our research indicates...