SEATTLE, Washington (AP) -- A professor at the University of Washington Medical School who moved to Botswana to help alleviate a shortage of doctors there, was killed when a crocodile dragged him from a dugout canoe, his family and colleagues said. Richard K. Root, 68, was on a wildlife tour of the Limpopo River in remote northeastern Botswana with his wife, Rita O'Boyle, on Sunday when it happened. The couple had been visiting a clinic in the area. A nationally known expert in infectious disease and the former chief of medicine at Harborview Medical Center here, Root went to the...