WASHINGTON - Santino the chimpanzee has always been known for throwing rocks, but his attacks on annoying zoo visitors have gotten more complex - proof that this is one smart chimp.
Housed at the Furuvik Zoo in Sweden, Santino has improved his rock throwing technique by planning his attacks for a more surprising affect.
A researcher who studied Santino told Discovery News the monkey recently began moving piles of hay close to the visitors section of his enclosure and hiding rocks and projectiles underneath. Santino then waits patiently for visitors to get close, then throws the rocks at them.
"What is interesting is that he made these preparations when the visitors were out of sight, and also that he incorporated innovations into the behavior," researcher Mathias Osvath tells Discovery.
The 31-year-old chimp is the dominant male in his exhibit, and researchers say the behavior of throwing things at visitors is not unique. It's the pre-planned attacks that set Santino aside.
"Some apes throw sticks or feces, but Santino doesn't have access to any good sized sticks, and he really dislikes putting his fingers on gooey stuff, including feces," Osvath says.
To see a picture gallery of Santino, click here.
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