Adult gentoo penguins keep an eye on their newly born chick at Edinburgh Zoo on June 10, 2011 in Edinburgh, Scotland. The gentoo chicks which started hatching in early May are looked after by both parents who regurgitate part digested food. When the chicks are hungry they peck the beaks of their parents to signal feeding time. (Photo by Jeff J Mitchell/Getty Images)

Actor Brad Pitt films a scene from “World War Z” in Glasgow City centre on August 18, 2011 in Glasgow, Scotland. The film, which is set in Philadelphia, will be shot in various parts of the city transforming it into ruins to shoot a post apocalyptic zombie film. (Photo by Jeff J Mitchell/Getty Images)