"Most animals don't make/use tools, in the main, save useful adaptations and behaviours they have been endowed with. It is possible, however, someday we'll see an ape fashion a ladder and escape from a zoo."
Well, chimpanzees fashion simple tools. That is to say, they will alter a stick in various ways to make it more efficient to poke ants of an anthill, etc.
Good example.
Studying the gorillas recently at San Diego Wild Animal Park, I was practically hoping to see three or four of them climb on each other's shoulders and have at least one run free of the enclosure. Then I noticed the wires around the moat's periphery attached to insulators...