A panda walks into a cafe. He orders a sandwich, eats it, then draws a gun
and fires two shots in the air.
"Why?" asks the confused waiter, as the panda makes towards the exit. The
panda produces a badly punctuated wildlife manual and tosses it over his
shoulder.
"I'm a panda," he says, at the door. "Look it up."
The waiter turns to the relevant entry and, sure enough, finds an
explanation.
"Panda. Large black-and-white bear-like mammal, native to
China. Eats, shoots and leaves."
This joke is found on the back cover of the book Eats, Shoots & Leaves by Lynne Truss, a funny little book about the necessities of punctuation.