The species would have looked similar to modern rats but ranged in size from about 1.5 kilograms to five kilograms. Researcher Julien Louys said the creatures were probably herbivores and became extinct suddenly about 1,000 years ago. He said they were the largest known rats to have ever existed and acknowledged some people thought they sounded terrifying. "Most people seem to think that," Dr Louys said. "But I think they would have been, well not cute, but certainly they would have been fascinating to see them in the flesh." He said it appeared the rats were a popular meal for...