"Long before it's in the papers"
September 04, 2015

RETURN TO THE WORLD SCIENCE HOME PAGE


Chimp attacks drone with stick, wins

Sept. 4, 2015
Courtesy of Springer Journals
and World Science staff

Cool. Calm. And oh, so cal­cu­lat­ed. That’s how a chimp at a Dutch zoo, us­ing a long stick, swat­ted down an aer­i­al drone that was film­ing her group, sci­en­tists say.

In an ar­ti­cle in the jour­nal Pri­ma­tes, re­search­ers Jan van Hooff and Bas Lukke­naar ex­plain it as yet an­oth­er ex­am­ple of chim­panzees’ make-do at­ti­tude to us­ing what­ev­er is on hand as tools.

A female chimp named Tushi uses a stick to "attack" the drone. Behind her Raimee is sitting also with a long stick. (Credit: Royal Burgers' Zoo)


The in­ci­dent hap­pened on April 10, when a Dutch tel­e­vi­sion crew was film­ing at the Roy­al Burg­ers’ Zoo in Arn­hem, the Neth­er­lands.

The idea was to use a drone to film the chimps in their com­pound from dif­fer­ent close-up an­gles. 

The drone caught the apes’ at­ten­tion dur­ing a prac­tice run, the re­search­ers said. Some grabbed wil­low twigs off the ground, while four an­i­mals took these along when they climbed up scaf­fold­ing where the drone was hov­er­ing. This be­hav­ior is­n’t of­ten seen among these chimps.

Film­ing started when the next drone flew over. It zoomed in on two chim­panzees, the fe­males Tushi and Raimee. They were still seated on the scaf­fold­ing hold­ing on to twigs that were about 180 cm (a­bout six feet) long. 

Tushi made two long sweeps with hers, and the sec­ond took down the drone and ul­ti­mately broke it, the sci­en­tists said. Be­fore and dur­ing the strike, she grim­aced. Al­though her face was tense and her teeth were bared, she showed no signs of fear, they added, sug­gest­ing she struck de­lib­er­ate­ly, not re­flex­ive­ly.

“The use of the stick as a weap­on in this con­text was a un­ique ac­tion,” said van Hooff. “It seemed de­lib­er­ate, giv­en the de­ci­sion to col­lect it and car­ry it to a place where the drone might be at­tacked.”

“This ep­i­sode adds to the in­dica­t­ions that chim­panzees en­gage in for­ward plan­ning of tool-use acts,” Lukke­naar said. The in­ci­dent al­so showed the apes cau­tiously in­spect­ing the con­trap­tion and even throw­ing it around be­fore they lose in­ter­est in it.

Ac­cord­ing to van Hooff and Lukke­naar, the chim­panzees at the zoo have nev­er ex­plic­itly been taught tool use, but have had am­ple chance to watch hu­mans han­dle all kinds of im­ple­ments. 

Pre­vi­ous stud­ies showed that the chimps at this Dutch zoo spon­ta­ne­ously and in­no­va­tively use up to 13 types of tools in a va­ri­e­ty of ways, es­pe­cially uti­liz­ing sticks of dif­fer­ent sizes. The apes seem to choose the size, shape and weight of the tools with a par­tic­u­lar use in mind, ac­cord­ing to the re­search­ers. Sticks are, for in­stance, used to gath­er fresh leaves from overhead branches, while heavy pieces of wood and stones are cho­sen as throw­ing weap­ons.


* * *

Send us a comment on this story, or send it to a friend











Sign up for
e-newsletter

   
 
subscribe
 
cancel

On Home Page         

LATEST

  • Gi­ant sea scor­pion fos­sils turn up

  • Sex buy­ers, sex­ually ag­gres­sive men often the same peo­ple, study finds

EXCLUSIVES

  • Study links global warming, war for first time—in Syria

  • Smart­er mice with a “hum­anized” gene?

  • Was black­mail essen­tial for marr­iage to evolve?

  • Plu­to has even cold­er “twin” of sim­ilar size, studies find

MORE NEWS

  • F­rog said to de­scribe its home through song

  • Even r­ats will lend a help­ing paw: study

  • D­rug may undo aging-assoc­iated brain changes in ani­mals

Cool. Calm. And oh, so calculated. That’s how a chimp at a Dutch zoo, using a long stick, swatted down an aerial drone that was filming her group, scientists say. In an article in the journal Primates, researchers Jan van Hooff and Bas Lukkenaar explain it as yet another example of chimpanzees’ make-do attitude to using whatever is on hand as tools. The incident happened on April 10, when a Dutch television crew was filming at the Royal Burgers’ Zoo in Arnhem, the Netherlands. The idea was to use a drone to film the chimps in their compound from different close-up angles. The drone caught the chimpanzees’ attention during a practice run, the researchers said. Some grabbed willow twigs off the ground, while four animals took these along when they climbed up scaffolding where the drone was hovering. This behavior isn’t often seen among these chimps. Filming started when the next drone flew over. It zoomed in on two chimpanzees, the females Tushi and Raimee. They were still seated on the scaffolding holding on to twigs that were about 180 cm (about six feet) long. Tushi made two long sweeps with hers, and the second took down the drone and ultimately broke it, the scientists said. Before and during the strike, she grimaced. Although her face was tense and her teeth were bared, she showed no signs of fear, they added, suggesting she struck deliberately, not reflexively. “The use of the stick as a weapon in this context was a unique action,” said van Hooff. “It seemed deliberate, given the decision to collect it and carry it to a place where the drone might be attacked.” “This episode adds to the indications that chimpanzees engage in forward planning of tool-use acts,” Lukkenaar said. The incident also showed the apes cautiously inspecting the contraption and even throwing it around before they lose interest in it. According to van Hooff and Lukkenaar, the chimpanzees at the zoo have never explicitly been taught tool use, but have had ample chance to watch humans handle all kinds of implements. Previous studies showed that the chimps at this Dutch zoo spontaneously and innovatively use up to 13 types of tools in a variety of ways, especially utilizing sticks of different sizes. The apes seem to choose the size, shape and weight of the tools with a particular use in mind, according to the researchers. Sticks are, for instance, used to gather fresh leaves from overhead branches, while heavy pieces of wood and stones are chosen as throwing weapons.