Remember the chimp at a Dutch zoo who emphatically swatted a TV crew's drone out of the sky with a tree branch? Researchers who dissected Tushi's actions have concluded she planned the attack, sort of like a human would. 
 
 In a study recently published in the journal Primates, Jan van Hooff and Bas Lukkenaar re-examine the events of April 10, when a Dutch TV crew was using a camera-equipped drone to film a documentary of chimpanzees at a 1.7-acre enclosure at the Royal Burgers Zoo in Arnhem. 
 
 Some of the chimps grabbed branches or twigs from willow trees and two females, Tushi and Raime, climbed up on scaffolding. 
 
 As the drone got close, Tushi swatted at it twice with a 6-foot-long branch she brandished in her left hand. The second swipe made contact, knocking the drone to the ground. The camera continued to film, capturing the inquisitive faces of the chimps as they inspected and toyed with the perplexing gadget. 
 
 Related: Chimps Might Have More Evolved Hands Than Humans 
 
 The study's authors note that Tushi grimaces just before and during the act of striking. "The precise coincidence of the facial grimace with the strike suggests that it is a concomitant of an assertive and determined exertion of force, homologous to what humans do in comparable situations." 
 
 Play Facebook 
 
 Twitter 
 
 Embed Do Chimps Have Accents? 1:32 autoplay autoplay Copy this code to your website or blog 
 
 The researchers note that Tushi collected the stick before the drone approached, and carried it to a place where the drone might be swatted. The sequence of events, they say, suggests the attack was "planned" and "deliberate." 
 
 "This episode adds to the indications that chimpanzees engage in forward planning of tool-use acts," they write. ||||| Incident shows that chimps are able to plan ahead and use tools as weapons 
 
 New York | Heidelberg, 3 September 2015 
 
 Cool. Calm. And oh, so calculated. That’s how a chimpanzee living in the Royal Burgers’ Zoo in the Netherlands set out to swat an aerial drone that was filming her group. In an article in the journal Primates published by Springer, 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 earlier this year, on 10 April, when a Dutch television crew was filming at the zoo in Arnhem. The idea was to use a drone to film the chimpanzees in their compound from different close-up angles. The drone already caught the chimpanzees’ attention during a practice run. 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 is not frequently observed 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 (ca. six feet) long. Tushi made two long sweeps with hers – the second was successful in downing the drone and ultimately broke it. Before and during the strike, she grimaced. Although her face was tense and her teeth were bared, she showed no signs of fear. This suggests that she quite deliberately and forcefully struck at the drone, rather than fearfully or reflexively. 
 
 
 
 
 
 “The use of the stick as a weapon in this context was a unique action,” comments 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 says, explaining the broader significance of the filmed event. This incident also shows 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 housed at the Royal Burgers Zoo have never explicitly been taught how to use different tools, 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 appear to choose the size, shape and weight of the tools with a particular use in mind. Sticks are, for instance, used to gather fresh leaves from overhead branches, while heavy pieces of wood and stones are chosen as throwing weapons. 
 
 
 
 
 
 
 
 References: 
 
 1. Van Hooff, J.A.R.A.M. & Lukkenaar, B. (2015). Captive chimpanzee takes down a drone: tool use toward a flying object, Primates. DOI 10.1007/s10329-015-0482-2 
 
 2. Primates is the official journal of the Japan Monkey Centre. 
 
 3. The article has been made freely available online for everyone under the Springer Open Choice program. 
 
 Caption: 
 
 A female chimpanzee named Tushi uses a stick to “attack” the drone. Behind her Raimee is sitting also with a long stick | © Royal Burger’s Zoo 
 
 Further Information 
 
 About the journal Primates 
 
 About the Japan Monkey Centre 
 
 Services for Journalists 
 
 The full-text article, photos and a video are available to journalists on request. 
 
 Contact 
 
 Katrin Petermann | Springer | Corporate Communications 
 
 tel +49-6221-487-8414 | katrin.petermann2@springer.com ||||| Studying the origin of laughter and smiles could help researchers better understand disorders such as autism. This condition is characterized, in part, by difficulties communicating via such signals, and in forming relationships with others. The research also helps us to better understand the abilities of non-human primates, and our evolutionary connections to them. As this image and the one before it show, there's not much difference between a chimp "laugh face" and the typical expression of humans as they enjoy a good guffaw. 
 
 So far, observations of chimps show they are always honest laughers, meaning that the sounds function as true signals of joy. People, on the other hand, are notorious for fake laughter. We can smile and laugh as though we are happy, even when we're not. There is, however, a complex twist to chimp laughter: what elicits happiness in some might not in others. "I've seen adolescent males (chimps) who sometimes exhibit bullying behavior, laughing softly while they are picking on another chimpanzee, who is usually not enjoying the interaction," Bard said. "When the victim gets annoyed enough to try to stop the bullying behavior, then the adolescent can respond with greater laughter, which is even more annoying!" "So the laughter is 'joyful,'" she said, "but the adolescent finds picking on another chimpanzee, and even their attempt at retaliation, to be something that brings the adolescent some joy." Wild Chimps Glug Alcohol Using Homemade Tools 
 
 Since laughter is seen and heard by others, it works wonders as a social bonding tool. In this case, the baby chimp is laughing as its mother tickles its stomach. The researchers suspect that bonobos, like chimps and humans, also benefit from this type of bonding, and have very flexible facial expressions and vocalizations. Video: Why Are We Ticklish? 
 
 Both young chimps and children tend to laugh and smile a lot, probably because they play more than adults do (and have less to worry about). But why would teeth be exposed as a sign of friendliness? Some experts suspect that the open mouth/exposed teeth expression, during non-threatening play times, allows the other individual to learn how to assess others and to adjust their reactions. Another theory is that a toothy smile often is a visual signal of submissiveness, given that the jaws are usually drawn backward as opposed to the forward thrust of a "grrr" sound and related facial expression. Apes Enjoy Slapstick Humor 
 
 Little Callie the chimp, shown in this photo, is enjoying a good laugh with a human friend. Chimps, like people, sometimes laugh and smile when they are alone, too. "We know that laughter and open mouth faces occur mostly during play, but they can occur in solitary play as well as social play," Bard said. "So our current theory is that laughter (in chimps) is typically associated with feelings of joy." Chimps 'Talk' About Their Favorite Foods, Trees 
 
 In both humans and chimps, facial expressions associated with laughter and happiness usually involve an open mouth with a display of teeth. "Open mouth expressions, otherwise known as play faces, or as we call them, laugh faces, typically expose the lower teeth by virtue of the mouth being wide or stretched open," co-author Kim Bard, who is a professor of comparative developmental psychology at the University of Portsmouth, told Discovery News. "We found that there were many types of open mouth expressions, including some configurations with the upper lip drawn up, which sometimes exposes the upper teeth." 6 Shocking Things About Chimps 
 
 Laughs and smiles in chimps turn out to be far more human-like than previously thought and they date to at least 5 million years ago, suggests a new study on chimpanzee facial expressions and vocalizations. Laughter is not 100 percent identical between the two primates, but people who hear a chuckling chimp usually have little trouble figuring out what the sound generally means. Chimps go "h-h-h," while humans sound more like "ha-ha-ha" or "he-he-he," said Marina Davila Ross, a senior lecturer in the University of Portsmouth's Department of Psychology and lead author of the study in PLOS ONE. Then there is the flexibility of the sounds and related expressions. "Chimpanzees, like humans, can produce their facial expressions free from their vocalizations," Ross explained. "This ability is important for humans. For instance, it allows us to add a smile while talking or laughing, and we can also produce smiles silently. Until now, we did not know that non-human primates also have this ability." It's even possible that the skills first emerged in the common ancestor of chimps and humans. Video: Apes Giggle Like Humans 
 
 This collection of stones inside a tree hollow might look innocuous, until you remind yourself that chimps did it. The elusive question is "why?" 
 
 In behavior never before seen, chimpanzees in West Africa have been filmed picking up stones and throwing them at trees, all the while making “hooting” vocalizations. 
 
 The resulting accumulation of stones either next to or in the hollows of the trees has created a new puzzle for chimp researchers: 
 
 Scientists from the Max Planck Institute for Evolutionary Anthropology (MPI-EVA) made the discovery with the help of camera traps, placed after field teams noticed piles of stones next to trees at some of their dozens of research sites. 
 
 Chimps Chuckle, Smile Much Like Humans Do: Photos 
 
 The behavior was exhibited primarily by adult male chimps, but the scientists said some females and juveniles were also seen throwing the stones. 
 
 Data on these observations have just been published in the journal Scientific Reports. 
 
 “This study reports a new chimpanzee behavior not known,” said Christophe Boesch, a study co-author from the MPI-EVA, in a press release. “As the stone accumulation behavior does not seem to be linked to either the abundance of stones or the availability of suitable trees in an area, it is likely that it has some cultural elements.” 
 
 Chimps Trust Some People More Than Other Chimps 
 
 Chimps are known to use tools when foraging for food, such as using sticks to poke around for termites or to extract honey or ants. They’ll also use stone or wooden “hammers” to smash nuts open. 
 
 But the researchers say the stone-throwing activity doesn’t seem to have anything to do with foraging. 
 
 “This represents the first record of repeated observations of individual chimpanzees exhibiting stone tool use for a purpose other than extractive foraging at what appear to be targeted trees,” the authors of the study wrote. 
 
 Chimps Communicate Like Passionate Italians 
 
 Why chimps might throw stones in this manner is still an open question. But the researchers have some ideas. 
 
 Study co-author Laura Kehoe wrote in The Conversation that the scientists' current theories revolve around the rock-throwing being part of a male display; a sort of pathway or territory signpost; or perhaps even a marking of "sacred trees." 
 
 Of the latter, Kehoe wrote: "Indigenous West African people have stone collections at 'sacred' trees and such man-made stone collections are commonly observed across the world and look eerily similar to what we have discovered here." 
 
 Researchers on the study have been working under the aegis of the collaborative “Pan African Program: The Cultured Chimpanzee,” which has, since 2010, gathered data on chimpanzees across 39 research sites in Africa. Its public website Chimp&See lets visitors pore over video gathered by the program.
– A chimpanzee that famously knocked a flying drone out of the air with a stick earlier this year wasn't reacting out of fear or annoyance but rather executing a pre-planned and deliberate attack. That's according to a new study in Primates. "This episode adds to the indications that chimpanzees engage in forward planning of tool-use acts," researcher Bas Lukkenaar says in a press release. The Christian Science Monitor reports a Dutch TV crew was using the drone to film a documentary on the chimps at the Royal Burgers' Zoo in April. After a test-run with the drone, the chimps started collecting sticks and climbing scaffolding. When the drone returned, a chimp named Tushi was ready, swiping it out of the air with a 6-foot branch. While studying footage from the busted drone, researchers focused on Tushi's facial expression during the attack, NBC News reports. They found the grimace she makes before and during the incident is similar to what humans do while carrying out a predetermined use of force. According to the press release, the lack of fear in Tushi's expression means she wasn't simply attacking out of reflex. The Monitor explains it's the difference between a calculated plan and swatting at a mosquito. This isn't unusual behavior for the chimps at Burgers' Zoo; they've taught themselves to use 13 different types of tools, the press release states. (Now find out how chimps are more advanced than humans.)