POLICY-MAKERS are scrabbling to contain the spread of the coronavirus, as more highly transmissible variants travel around the world. Yet the evolution of SARS-CoV-2 in this way comes as no surprise to virologists. In fact, it is probably just one step on a much longer evolutionary trajectory. In time, virologists predict, the virus will become more benign, following an evolutionary pathway previously taken by four other human coronaviruses that today cause nothing more than the “common cold”. How could this happen, and how will …