Why the wolf was brought back to the US in the 1990s and the history of "rewilding", plus the liberation of Paris 75 years on, the missing children from El Salvador's civil war, the life and death of Brazil's legendary president Vargas, and the man who wanted to be a cyborg.

Photo:.A Yellowstone wolf watches biologists after being tranquilized and fitted with a radio collar during wolf collaring operations in Yellowstone National Park (William Campbell/Sygma via Getty Images)