Scientists have found evidence that an earthquake 3,800 years ago in Northern Chile is the largest in human history, according to a new study. The quake had a magnitude of around 9.5, prompting tsunamis that struck countries as far away as New Zealand and boulders the size of cars to be carried inland by the waves, according to researchers at the University of Southampton. Since earthquakes occur when two tectonic plates rub together and rupture, a longer rupture indicates a bigger earthquake, they said. "It had been thought there could not be an event of that size in the north...