Chimpanzee stacked rocks to hurl at humans

A CANNY chimpanzee who calmly collected a stash of rocks and then hurled them at zoo visitors in fits of rage has confirmed that apes can plan ahead just like humans, a Swedish study says.
Santino the chimpanzee's anti-social behaviour stunned both visitors and keepers at the Furuvik Zoo but fascinated researchers because it was so carefully prepared.
According to a report in the journal Current Biology, the 31-year-old alpha male started building his weapons cache in the morning before the zoo opened, collecting rocks and knocking out disks from concrete boulders inside his enclosure.