We went to the zoo recently and was walking down to the tiger enclosure. We saw a man had jumped over the fence into the greenery to retrieve his glasses that 'fell off' and subsequently the tigers all came to the front of their enclosure.
I can't think why he wouldn't ask a zookeeper to safely get them or was he just trying to get the tigers closer for a better pic?! Either way my face was 
I've attached a wonderful diagram. Very proud of it 