A new paper explores how gene-editing technology could be used to bring a species back, but even its authors have concerns about what that could mean. If Tom Gilbert could bring any extinct animal back to life, he said, it wouldn't be dinosaurs or woolly mammoths or any other megafauna that once roamed the planet. His is a humbler choice: the Christmas Island rat, a species that was wiped out from its island home in the Indian Ocean more than a century ago. Gilbert, an evolutionary geneticist at the University of Copenhagen, Denmark, admitted that his pick may not be...
