Stefan Nolan from Cork, Ireland, paid a visit to Germany with four friends and decided to visit Berlin Zoo on November 17. No doubt they were expecting a warm welcome, but one bad-tempered gorilla was in no mood to greet tourists. Stefan was recording the gorilla in his enclosure when the surly animal tossed a rock in his direction. Stefan later tweeted that the gorilla also tossed a massive clump of dirt at another visitor before leaving. Credit: YouTube/Stefan Nolan