From the Guardian:
The loutish behaviour of a stone-throwing chimpanzee at a zoo near the Arctic circle has challenged scientists’ beliefs about human beings.
Santino, a 31-year-old male at Furuvik zoo in Sweden, may be the first animal to exhibit an unambiguous ability to plan for the future, a behaviour many scientists argue is unique to humans. Forward planning takes considerable cognitive skills, because it requires an animal to envisage future events it will have to deal with.
Santino would get agitated when the first groups of visitors arrived at his enclosure in the morning, and would start hurling stones at the spectators. When the zookeepers investigated, they found that, while the zoo was closed, Santino had been busy making piles of ammunition, and returned to them to resupply.
To catch the chimp in action, one zookeeper hid in a room overlooking the enclosure and observed the ape’s behaviour before the zoo gates opened each morning. She saw Santino dragging stones from a protective moat that surrounded his island home, before placing them in piles. Further covert surveillance of the ape revealed he spent some time tapping areas of concrete floor with his fist. Occasionally, the animal would thump harder, releasing chunks of concrete that he broke into rough discs.
A survey of the enclosure showed that Santino made piles of ammunition only on the quarter of the island’s shore that faced the visiting crowds.
Since becoming aware of the issue, zookeepers have removed hundreds of caches of stones from the island and have observed Santino gathering stones and putting them in piles at least 50 times. Santino’s attempts to fashion concrete discs has been recorded 18 times, according to a report in Current Biology.
