Scientists will likely discover the origin of the Covid-19 pandemic within the next few years, after they pursue and zero in on an animal source for the new coronavirus, a member of an international team of investigators led by the World Health Organization said Wednesday. “I’m convinced we’re going to find out fairly soon,” said Peter Daszak, a member of the WHO-led team and a zoologist who specializes in hunting for viral origins in animals. “Within the next few years we’ll have real significant data on where this came from and how it emerged.” Dr. Daszak was one of three...