Chimp Gathers Stones for "Premeditated" Attacks on Zoo Visitors

By Eliza Strickland | March 9, 2009 2:30 pm

chimp stonesA belligerent chimpanzee in a Swedish zoo that stockpiles projectiles to hurl at visitors may be the first definitive proof that some animals can plan far ahead, researchers say. For years a male chimp named Santino has collected stones and other potential missiles into caches around his enclosure, which he returns to hours later when he wants to attack visitors. Researchers say the behavior proves that Santino was planning for the future because he collected the stones in a calm state, prior to the zoo opening in the morning. The launching of the stones occurred hours later – during dominance displays to zoo visitors – with Santino in an “agitated” state [BBC News].

Lead researcher Mathias Osvath says the behavior reveals an advanced animal intelligence. “These observations convincingly show that our fellow apes do consider the future in a very complex way…. It implies that they have a highly developed consciousness, including lifelike mental simulations of potential events” [AP], he says.

In the new study, published in Current Biology, researchers note that Santino doesn’t just collect stones from the moat that surround the zoo’s “chimpanzee island,” he also fashions projectiles from concrete rock structures within his enclosure. “The chimpanzee was observed to gently knock on the concrete rocks, from time to time delivering harder blows to break off the detached surface in section in discoidal pieces, and sometimes breaking these into further smaller fragments,” Osvath explained, adding that “these manufactured missiles were often transported to the caches at the shoreline” [Discovery News].

Santino, a 30-year-old chimp, is the only male in his small social group; he only engages in his displays of hurling during the summer months when the zoo is open to visitors. Zookeepers have tried to rein in the unruly Santino by confiscating his caches of weapons, but they admit that it’s hard to foil a smart and determined chimp. Says Osvath: “It’s very hard to stop him because he can always find new stones, and if he can’t find them he manufactures them. It’s an ongoing cold war.” He adds that since chimps don’t have a good aim, and throw underarm, there haven’t been any serious injuries [New Scientist].

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Image: Mathias Osvath/Current Biology

CATEGORIZED UNDER: Living World, Mind & Brain
  • Seth

    I would shit myself if I were a YEC right now.

  • lizz bronson

    i am fascinated by this development; and the surprise reaction to the very idea that this chimp can plan for the future or display gathering and a thought process. chimps are accustomed to live in the wild, in social groups. this chimp obviously knows it is in a setting that is not natural to him. there is evidence that chimps and non human primates in general have reactions when humans enter the picture.

  • Clute

    This is quite something! And to think that there are some human beings that is not capable of planning for tomorrow…

  • http://n/a john

    what makes this so surprizing is that it has taken so long for “experts engaged into reseaches of thinking styles ” to consider it possible to occur at levels which demonstrate thought and expression of disgust with other species is possible to be dispayed at any level in animals to realize this is a fact of life for them, they can and do think.
    too bad the educated persons of the world as represented by this researcger have not yet to learned to listen to and consider the validity of the celtoids perception that if you want to learn about the world and then about yourself you must first listen to what tha animals around you are teaching by act or by thier way of “talking ” to you.
    if you want a good illustration of that take some time to watch what a good sheep dog does, the pyr and the greater swissies or a cross border collie to a gordon seem to be able to match in thier own way what this gorrilla has been doing for years, wether it is to show as i suggested earlier how disgusted he is with people in general or just a few who treat him like a animal ony he knows the truth of, if somehow the expert is able to unravel the mystery of how the celts spoke to the animals and leaned thier secrets that would be a giant springboard by which to go beyond this leap into they way we act nd react to situations we meet as humans and or as animals. thisimportant first step is one which i beleive is in itself is a start to understanding not just animal; but human behaviour and thinking (when or if it done) processes begin and we if we do consider the results of our actions allow the humans of the world to consider each omes affect on oneself and opnes neighbour, human or animal.i am not a bhuddist or adherent to any organized religion so please do not ascribe a eleemnt of those philosophies to my have presented the foregoing.

  • Bob Snyder

    Wow, why does this article attract people with poor grammar and terrible spelling?

  • Katie

    All of the accounts I have seen about this through various media outlets focus on the idea that this
    situation presents new evidence that
    animals other than humans demonstrate planning and forethought.

    Personally, I have never questioned that chimpanzees are quite
    intelligent and have the capacity both to strategically plan and to
    later implement these plans. What I have questioned, however, are the
    ethics surrounding keeping such an intelligent animal captive in a zoo
    environment. In addition to being evidence of advanced intelligence,
    doesn’t this say something about a chimpanzee’s experience in a zoo
    environment – or,at the very least, about Santino’s experience in the
    Swedish zoo?

    Santino has been engaging in this behavior for ten years. Maybe in the
    midst of all of this research, someone should hypothesize about what
    Santino might be communicating through this behavior. I sincerely
    doubt his primary goal was to demonstrate to humans that he is capable
    of forethought and planning.

  • Patrick

    In regards to Seth:

    “I would shit myself if I were a YEC right now”

    No you would not. You would simply say that Satan was contolling a mindless creature to confuse disbelievers.

    Self delusion, has no logical limitation, as it needs none

  • warthpublishinginc

    If chimps are so smart, why do they poop all over the place. Even cats know enough to deficate in certain areas.

  • steve

    “Damn you… Damn you all to hell”

  • cacs

    Researchers are just on to this? I remember seeing orangutans years ago at the San Diego Zoo who lured zoo visitors to come close, then lobbed poop at them. It happened over and over with unsuspecting gawkers, lulled by the orangutans’ acting all cute and innocent while hiding their hoard of dung until their targets were within range.

  • Rogue Warrior

    Seems some of you missed parts of the article. He only does this behavior in the summer when the zoo is open. It seems like a dominance action. He is the ONLY male in his group. He must feel threatened by the perceived pack of possible threats to his anarchy. He therefore is thinking ahead and coming up with weapons for mass destruction. He realise’s that he cannot get at the people so he thows stuff. Very smart. Hes doesn’t feel threatened by the zoo overall or he would be acting out all year. The staff may be all female, would be interesting to know what the male/female staff interaction is or if the staff interacts at all. But he doesn’t seem to be worried about the staff. Just the horde of intruders coming to close to his group. And if you dont like the spelling and bad penmanship, well to bad. you read it already, get over your selfrightousness. Spelled alot wrong on purpose just for you.

  • adam

    The line about this being the first definitive proof that some animals can plan far ahead is silly.

    Here’s an article about dolphins trained to fetch litter from their pools. In return the dolphins are given a fish. One dolphin started hoarding all the trash under a rock in her enclosure and only would bring the trainers one small bit at a time.

    Also, what about squirrels and other animals that hoard food?

  • Jay

    Maybe they were sick of people throwing things at them and teasing them. Even a well trained dog will bite if it is threatened.

    Doesn’t mean they are are getting smarter. Other wise goldfish would rule the world because every time someone taps on the glass they are getting fed, and learning.

    No matter hard you try, it is still a primate. Learned responses and all.

  • Rogue Warrior

    This isn’t a learned response. They do this naturally in the wild. They will find anything handy to throw and throw it to intimidate or protect. (Have you ever watched Gorillas in the Mist) If the throwing doesn’t work, (they have already banged their chests ect). Eventually they will get physical. Most all animals have some sort of cause and effect regarding protecting their brood. Geez even Big Foot has been said to throw stones!! The interesting thing is the planned stockpiling for the event. But as Adam points out, it is not new. Although hoarding food is not the same as a planned arsenal of rocks. It is instictive and to go, from food to a planned arsenal of rocks… Very interesting take.

  • Catherine

    Warth, Chimps were not brought into the human cave/hut/domicile to cohabitate, as cats were, thousands of years ago. If they had been, you’d find them doing a fairly good job on the tiolet, probably better than most 3 year old humans, and certainly better than a human with too much alcohol in his/her system.

  • Corinne Tabb

    why do scientist state the obvious as some wonderful new discovery- duh!

  • http://n/a john

    well mr. snyder you appear to have a superior to most knowledge of grammar and spelling,t that is quite evident as is your poficency at sacasm.
    i challenge you in the capscity of a grammarian lexicograher to point out those errors in spelling, grammar and mores thamn likey evident in punctuation and syntax. if you are willing to educate me on the “correct” forms of any of the above please do so. it will beinteresting to see how you yourself are corrected by other readers of blogs or comment they may wish to attach to this post.
    now i add the challenge of asking you to add a few items to the dish of crow you will no doubt not relish dining on
    (a) unlike you appear to have i do not enjoy the full benefit of function in my hands at the keyboard, shatterred digital phalangei ensure that
    (b) having bi- lateral carpal tunnel syndrome reduces the ability to select keys in a manner that may appear to intend words to be mispelt is not a willed choice
    having a.d.h.d co-morbid with multiple a.b.i. tramae does sometimes affect my ability to recognize misppellings and grammatical error
    e) use of a spell checker as well as one intended for correction of grammar appears to be the limit of your own capacities to communicate in written engish. i can on surmise by the haughtiness of your comments you are an american, that is most fortunate for myself and other readers of your diatribe. the use of either to correct the errors in communication that are made by the rest of the world which offend you so heavily are within the use of your american english language and educational systems, it is unfortunate the importance of educating the americamn student at any level the recogition that what is taught in your schools ids the ONLY correct method of communocating successfully and accurately. what a load of rubbish you spout!!!!!!!!!!!!
    write if you have the brains or intestinal fortitude to defend yourself and the appaliling ignorance you display as a product of the american education systems.

  • Eileen

    TONIGHT WE HAVE SEEN THE BIRTH OF THE PLANET OF THE APES !!!!!!!!!!!!!!!!!!!!!!!!!!!!!

  • Big Barney


  • Aidy

    Now this is intriguing. But not the first ‘known’ animal to have the ability to premeditate. Still, astounding news.


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