No matter where you look, just about every creature
is obsessed with:
sex, real estate, who's the boss, and what's for dinner.
The Intelligence of Chimps
(includes Chimpanzees, Bonobos, Orangutans, and Gorillas)
Chimpanzees are very much like humans,
smart, but often brutal and violent.
The mirror test is an experiment developed in 1970 by psychologist Gordon Gallup Jr. to determine whether an animal possesses the ability to recognize itself in a mirror. It is the primary indicator of self-awareness in non-human animals and marks entrance to the mirror stage by human children in developmental psychology. Animals that pass the mirror test are: Humans older than 18 mo, Chimpanzees, Bonobos, Orangutans, Gorillas, Bottlenose Dolphins, Orcas (Killer Whales), Elephants, and European Magpies. Others showing signs of self-awareness are Pigs, some Gibbons, Rhesus Macaques, Capuchin Monkeys, some Corvids (Crows & Ravens) and Pigeons w/training.
7-31-19 Monkeys can use basic logic to decipher the order of items in a list
Keeping track of rankings could be useful for monitoring social pecking orders in the wild. Monkeys can keep strings of information in order by using a simple kind of logical thought. Rhesus macaque monkeys learned the order of items in a list with repeated exposure to pairs of items plucked from the list, say psychologist Greg Jensen of Columbia University and colleagues. The animals drew basic logical conclusions about pairs of listed items, akin to assuming that if A comes before B and B comes before C, then A comes before C, the scientists conclude July 30 in Science Advances. Importantly, rewards given to monkeys didn’t provide reliable guidance to the animals about whether they had correctly ordered pairs of items. Monkeys instead worked out the approximate order of images in the list, and used that knowledge to make choices in experiments about which of two images from the list followed the other, Jensen’s group says. Previous studies have suggested that a variety of animals, including monkeys, apes, pigeons, rats and crows, can discern the order of a list of items (SN: 7/5/08, p. 13). But debate persists about whether nonhuman creatures do so only with the prodding of rewards for correct responses or, at least sometimes, by consulting internal knowledge acquired about particular lists. Jensen’s group designed experimental sessions in which four monkeys completed as many as 600 trials to determine the order of seven images in a list. Images included a hot air balloon, an ear of corn and a zebra. Monkeys couldn’t rely on rewards to guide their choices. In some sessions, animals usually received a larger reward for correctly identifying which of two images came later in the list and a smaller reward for an incorrect response. In other sessions, incorrect responses usually yielded a larger reward than correct responses. Rewards consisted of larger or smaller gulps of water delivered through tubes to the moderately thirsty primates.
7-17-19 Orangutan mothers tell infants where to go by scratching themselves
Orangutan mothers use loud scratches to tell their infants that it is time to leave one area and move to another, possibly to avoid attracting predators or other orangutans. Primate experts are increasingly interested in behaviours such as scratching, self-grooming and face touching, debating whether these activities are intentional or simply due to psychological or physiological arousal. Marlen Fröhlich at the University of Zurich in Switzerland and her colleagues noticed that wild Sumatran orangutans living in the trees of the Suaq Balimbing forest in Sumatra would sometimes scratch themselves in a loud and exaggerated way. “We have found individuals in the forest just from hearing these loud scratches above our heads,” says Fröhlich. The scratches are a “rhythmic, harsh sound” due to the leathery skin and long hair of the orangutans, she says, and are loud enough to be heard by humans at least 15 metres away in a noisy rainforest. In contrast, the normal self-maintenance scratches involve smaller movements, happen less regularly and are less noisy. Fröhlich and her colleagues analysed 1457 bouts of scratching produced by 17 different orangutans, including four mothers and their dependent offspring, and the behaviour that occurred before and after each. “We found that orangutan mothers use their loud scratches to tell their infants that it is time to leave,” says Fröhlich. These exaggerated scratches were overwhelmingly produced by mothers, shortly before moving. They were usually directed towards a dependent offspring who was paying attention to them and who responded by moving towards the mother, she says. As a result, these loud scratches could be reliably distinguished from regular self-maintenance scratches.
7-17-19 Chimps bond with each other and people after watching a film together
Chimpanzees who watch a short film with a human or another chimpanzee are more likely to approach that individual or to spend time near them. This shows they feel closer to those they have shared an experience with, just like we do. “To our surprise, we found that the chimps were also sensitive to this,” says Wouter Wolf at Duke University in North Carolina. It is widely recognised that shared experiences can bring people closer together, making them more likely to interact. For instance, after England recently won the Cricket World Cup in an astoundingly close finish, strangers in the stands hugged each other. “Shared experiences open a psychological door between people,” says Wolf. After studying this phenomenon in people, he wondered whether it exists in apes too. He and colleague Michael Tomasello got chimpanzees at a zoo in Leipzig, Germany, and a human unfamiliar to them to watch a 1-minute video of young chimps playing. Sometimes the computer screen was placed so both the chimp and the person could see it and each other, and sometimes it was placed so only the chimp could see it. The film was chosen to be interesting enough to keep the animals’ attention but didn’t feature adult chimps as that could be too arousing. Eye tracking was used to confirm that the animals were watching the video and also looking to see if the human was watching too. Afterwards, the chimps approached the human faster if they had watched the video with them than if they hadn’t – 15 seconds on average versus 28 seconds.
6-24-19 Capuchin monkeys’ stone-tool use has evolved over 3,000 years
A Brazilian site shows the animals’ long history of selecting various types of pounding devices. Excavations in Brazil have pounded out new insights into the handiness of ancient monkeys. South American capuchin monkeys have not only hammered and dug with carefully chosen stones for the last 3,000 years, but also have selected pounding tools of varying sizes and weights along the way. Capuchin stone implements recovered at a site in northeastern Brazil display signs of shifts during the last three millennia between a focus on dealing with either relatively small, soft foods or larger, hard-shelled edibles, researchers report. These discoveries, described online June 24 in Nature Ecology & Evolution, are the first evidence of changing patterns of stone-tool use in a nonhuman primate. “It’s likely that local vegetation changes after 3,000 years ago led to changes in capuchin stone tools,” says archaeologist Tomos Proffitt of University College London. The new findings raise the possibility that chimpanzees and macaque monkeys, which also use stones to pound and dig, have shifted their tool-use styles over the long haul, perhaps in response to climate and habitat changes, Proffitt says. Archaeological sites linked to apes and monkeys are rare, though. Previous excavations in West Africa unearthed nut-cracking stones wielded by chimps around 4,300 years ago (SN: 11/21/09, p. 24). Present-day chimps inhabiting the same part of Africa crack nuts with similar-looking rocks. Evidence of long-term changes in tools used by wild capuchins (Sapajus libidinosus) comes from a site in Brazil’s Serra da Capivara National Park. Excavations there have also yielded ancient human stone tools (SN: 10/18/14, p. 14). But the newly unearthed artifacts more closely resemble stone tools used by modern capuchins at the same site (SN: 11/26/16, p. 16), rather than Stone Age human implements, the researchers say.
6-21-19 Death of mother prompts adolescent chimps to look after their siblings
Adolescent chimpanzees adopt their younger siblings if their mothers die. The older siblings keep a close watch on the youngsters, protect them from threats, and give them lots of comforting snuggles. The finding adds to the evidence that chimpanzees can understand when others are suffering, and to some extent can help them. In line with this, a second study shows that chimpanzees have a strong emotional response when they see that another chimp, or a familiar human, is injured. “After individuals lose their mothers, they do receive attention from other individuals in their group, who are often their siblings,” says Rachna Reddy of the University of Michigan. She has now studied the adoptions in detail. Reddy was tracking a group of about 200 chimps in Kibale National Park, Uganda, when they were struck by a respiratory disease between December 2016 and February 2017. During the outbreak, 25 chimps died and 13 lost their mothers. Chimps spend their first five years being carried and nursed by their mothers, and another three staying close to them. They are then adolescents roughly from eight to 15 years old. Of the orphaned chimps, nine were under the age of 12, meaning they were adolescents or younger. Reddy followed four pairs of young chimpanzee siblings, where the older of the two effectively adopted the younger. The older chimps were 10-17 years old, while the younger siblings they adopted were 6-7 years old. Compared to the period before their mothers’ deaths, the pairs spent much more time together. They also groomed, reassured and consoled each other. “It was like they were both seeking physical contact all the time,” says Reddy. “They were sort of inseparable.”
6-7-19 Overbearing bonobo moms
Mothers have been known to nag their grown children to produce grandkids, but bonobo moms take the pressure to a whole new level. These moms are so determined to become grandmothers that they will stand by when their sons mate with a female and fight off any other males that try to disrupt the lovemaking. These overbearing ape moms also run interference, breaking up liaisons between females and males that aren’t their sons. Occasionally, mother and son even team up to attack the latter’s sexual rivals. This forceful maternal behavior is well documented, and a new study has concluded for the first time that it actually helps the sons thrive, reports DiscoverMagazine.com. Researchers found that wild male bonobos in Congo whose mothers were still with them fathered three times more offspring than bonobos whose mothers had died or left the group. Lead author Martin Surbeck, from the Max Planck Institute in Leipzig, Germany, says bonobo moms likely act as they do to “increase their reproductive success without having more offspring themselves.”
5-27-19 Monkeys use their 'eagle' call to warn each other about drones
How do you teach a monkey new tricks? Lab trials have proved difficult places to train monkeys to distinguish between sounds and take different actions in response. But in the forests of Senegal’s Niokolo-Koba National Park, researchers were astonished at the speed one species of monkey adapted its behaviour to a new sound. Julia Fisher and her team flew drones over one community of green monkeys (Chlorocebus sabaeus) in the area, to see what they made of a new flying object in their environment. They responded instantly, making alarm calls to warn one another of the prospect of a new threat. The vocalisations were distinct from the ones they made in response to models of leopards and snakes, but almost identical to calls made by a related species of monkey in response to eagles. The results suggest a hard-wired response to the perception of an aerial threat and the use of that specific call. The monkeys adapted so quickly to the new noise that they began scanning the skies and making the calls even when played a sound of the drone from the ground. The monkeys were never seen issuing alarm calls to birds of prey in the area, suggesting the birds they usually see are not considered a threat. The drones, however, seemed to be perceived as dangerous. “It’s certainly disconcerting, unpredictable, something they’ve not seen before, so it makes sense to alert everybody,” says Fisher. She says she was “blown away” by how rapidly the monkeys appeared to learn. “The listeners are smart. It’s almost impossible to get a monkey in a lab to do an audio task.” It is not clear why such learning is harder in a lab environment, she says.
5-23-19 Chimpanzees eat tortoises after smashing them open on tree trunks
Tortoise meat is supposedly so delicious it has led people to eat some species to extinction. Evidently chimpanzees enjoy it too, as a group of these apes has figured out how to crack open tortoise shells to eat the meat within.. The chimps in question live in Loango National Park in Gabon, west Africa. They have only got used to humans within the last three years, so little is known about their behaviour. Between 2016 and 2018, Tobias Deschner at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany and his colleagues observed 38 incidents of chimps trying to eat hinge-back tortoises, all but four of them successful. When a chimp found a tortoise, it picked it up and started hitting its underside – which is softer than the tough shell on its back – against a hard surface like a tree trunk. Once the tortoise had been cracked open, the chimp climbed into a tree to eat it. On one occasion, the group’s alpha male ate half a tortoise, then wedged the remainder into the fork of a tree and slept overnight in a nearby nest. He then returned the next day and ate the rest. The chimps only ate tortoises during the main dry season from May to October, when other food was plentiful. The tortoises may simply be easier to find then, says Deschner. “During the dry season the leaves are really dry, and then it’s amazing how much noise a tortoise can make just by moving around,” he says. Other groups of chimpanzees have devised other tools, such as using sticks to “fish” for termites and spear bush-babies, and using moss as a sponge to drink water. It is not clear why chimps in other groups, some of them studied for decades, do not eat tortoises. The reptiles are widespread in Africa, so availability is not the issue.
5-21-19 Chimps that mash potatoes challenge our understanding of tool use
Chimps have spontaneously figured out how to use a stick to mash a potato. The finding could prompt a rethink of how tool use develops in primate societies. Wild chimpanzees in Guinea climb palm trees to eat the trees’ “hearts”, which look like white asparagus. They use sticks to mash the hearts before eating them, like cooks using pestles and mortars. Chimps elsewhere don’t do this, suggesting that the behaviour is cultural and that Guinea chimps pick it up by copying each other. However, Claudio Tennie of the University of Tübingen in Germany is sceptical about copying. Many studies have demonstrated copying among chimps by showing them how to get food out of a puzzle box and seeing if they can then do it. Tennie says these studies are flawed because the chimps may simply be grasping how such boxes work and then figuring out how to open them themselves. To see whether chimps can work out such tricks on their own, Tennie and his colleague Elisa Bandini studied semi-wild chimps at the Chimfunshi Wildlife Orphanage in Zambia. The chimps had never seen stick-pounding. Bandini and Tennie gave them potatoes that had been boiled for 3 minutes: long enough to be edible, but still hard to eat. In three out of four groups, one chimp collected a stick and used it to mash the potato (American Journal of Primatology). “They redevelop these kind of behaviours on their own from scratch,” says Tennie. In a separate study involving Tennie, captive chimps figured out how to use sticks to dig up underground tubers, without ever having seen it done (PLoS ONE).
5-20-19 Bonobo mothers stand guard and chase off rivals while their sons mate
If your mum gets too involved in your love life, spare a thought for bonobos. Females of these great apes, which are closely related to chimpanzees, help their sons with hook-ups, guard the young lovers while they mate, and even haul rival males off females mid-sex. And it’s a strategy that works. Males whose mothers are in their group have three times the number of babies as those who don’t. It’s a strategy that’s akin to the “grandmother hypothesis” in humans, which says that older women can boost their reproductive success by helping their daughters rear children rather than having more offspring of their own. “Female bonobos can increase their fitness even if they don’t reproduce any more — but not through daughters, it’s through their sons,” says Martin Surbeck of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. Bonobos have an unusual social structure in that the top-ranking individuals are female, and sons usually stay with their mothers while young females leave to find new groups. These apes are also famed for having lots of sex, for social reasons, as well as reproduction. It happens whether or not females are fertile — although when they are fertile they are more desirable. Surbecks’ team has previously described the bonobo mothers’ over-involvement in their sons’ love lives while following a community of 35 animals in the Salonga National Park in the Democratic Republic of Congo. They found mating attempts are often disturbed by others, but mothers tend to hang around their sons and stop any such meddling. “If your son is copulating and another male tries to interfere, you chase this male away,” says Surbeck.
5-9-19 Chimpanzees observed ganging up on a leopard and stealing its food
A group of chimpanzees stole a freshly killed animal from a leopard, then ate it. It is the first time the apes have been seen challenging such a large and dangerous predator. The finding could show how ancient apes and hominins first gained access to meat as a food source, and hints at the origins of cooperative hunting. Michio Nakamura of Kyoto University in Japan and his colleagues study a group of wild chimpanzees living in Mahale Mountains National Park in Tanzania. On the morning of 15 November 2016, Nakamura and a colleague were observing the chimps when they noticed a leopard sitting nearby. It soon moved off, perhaps because some of the chimps made intimidating “waa barks”. A little later the group’s alpha male, Primus, arrived and led some of the chimps to a nearby tree, in which a female named Christina was sitting. All of them looked at a patch of thick bush on the ground. Then Christina climbed down, went into the bush, and pulled out the body of an antelope called a blue duiker (Philantomba monticola). It was freshly dead, with wounds on its throat that were still oozing blood. Over the next five hours, the chimps took turns to eat the duiker, consuming its intestines, right hind leg and left forelimb. Throughout this period, various lines of evidence indicate that the leopard was either continually present or kept returning to the scene – perhaps trying to recover the duiker. Chimpanzees intermittently made waa barks again, and at one point the leopard was sighted by one of the observers. Nevertheless, the chimps made no attempt to flee. The chimps had the advantage of numbers, says Nakamura. Leopards sometimes hunt lone chimps or mothers with dependent young, but in this case “there were some ten chimpanzees, including one adult male, rushing to the scene,” he says. The incident illustrates the advantages chimps gain from living in cooperative social groups, he says, pointing to their ability to mount coordinated hunts for prey like colobus monkeys.
4-26-19 Gorillas imitate humans
A park ranger’s selfie with two female gorillas standing up like humans went viral around the world this week, helping to raise awareness of gorilla poaching. The image was taken at a gorilla orphanage in Congo’s Virunga National Park, where the great apes were raised after poachers killed their parents. Innocent Mburanumwe, the park’s deputy director, said he and the other staff have looked after the two gorillas since their mothers were killed in 2007. The gorillas, he said, think of the rangers as their parents and try to behave like them, including by walking erect. There are only about 1,000 mountain gorillas left in the world.
3-7-19 Human encroachment threatens chimpanzee culture
Environmental disruptions reduce opportunities for social learning. From deep inside chimpanzee territory, the fieldworkers heard loud bangs and shouts. Hidden video cameras later revealed what the chimps in the Boé region of Guinea-Bissau were up to. Males were throwing rocks at trees and yelling. Researchers don’t fully understand why the apes engage in this rare behavior, known as accumulative stone throwing. And scientists may not have much time to sort out what’s going on. All four of Africa’s subspecies of chimpanzees are under threat from deforestation and poaching. That and other human activity may also be affecting chimp behaviors, including ones that many primatologists view as evidence of chimp culture — behaviors that are learned socially and transmitted through generations, Ammie Kalan and colleagues report online March 7 in Science. Such traditions as cave dwelling, using sticks to dig for honey and cracking nuts with stones are far less likely to occur in areas most impacted by humans, compared with more remote chimp territories, the team found. “Everyone thinks that if populations are declining … there would be some loss in the transmission chain that leads to cultural diversity in animals,” says Kalan, of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. “We’re the first to really show this.”
2-26-19 ‘Mama’s Last Hug’ showcases the emotional lives of animals
Primatologist Frans de Waal explores the roots of fear, laughter, empathy and more. During the last few weeks of her life, Mama, an elderly chimpanzee at a zoo in the Netherlands, received a special visitor. As Mama lay curled up on a mound of straw, biologist Jan van Hooff entered her enclosure. Van Hooff, who had known Mama for more than 40 years, knelt down and stroked the arm of the listless chimp. When Mama looked up, her vacant face erupted into a smile. She reached out to van Hooff, calling out as she patted his face and neck. For primatologist Frans de Waal, this touching scene isn’t difficult to interpret: Mama was happy to see her old friend. But such an interpretation has been taboo among many behavioral scientists, who have claimed nonhuman animals are like unthinking, emotionless machines that react to situations with preprogrammed instincts. In the thought-provoking Mama’s Last Hug, de Waal dismantles that view. He presents piles of evidence that animals are emotional beings. The book is a companion to Are We Smart Enough to Know How Smart Animals Are?, in which he explored animal intelligence (SN: 12/24/16 & 1/7/17, p. 40). Emotions, de Waal writes, “are bodily and mental states — from anger and fear to sexual desire and affection and seeking the upper hand — that drive behavior.” On page after page, he tells of depressed fish, empathetic rats, envious monkeys and other emotional creatures. More than a collection of fascinating anecdotes, Mama’s Last Hug weaves together formal observations of animals in the wild and in captivity, behavioral experiments and neuroscience research. That animals have emotions makes sense from an evolutionary perspective, de Waal explains. The basic physiology and brain chemistry that give rise to emotions in humans are present in other members of the animal kingdom. And emotions offer a much more flexible way to evaluate and respond to events in an ever-changing environment than instincts do.
2-13-19 Chimp sign language and human communication follow the same rules
Gestures used by chimpanzees to communicate with each other follow some of the same rules intrinsic to human language, according to a study of wild chimps living in Uganda. Raphaela Heesen, at the University of Roehampton in the UK, and colleagues analysed video recordings of more than 2000 uses of 58 different types of “play” gestures used by chimps living in the Budongo Forest. They found that more frequently used gestures were shorter in duration, and that longer signing sequences were made up of shorter, syllable-like gestures. These two patterns are known to apply to all human languages. “Primate gestural communication is, of course, very different to human language, but our results show that these two systems are underpinned by the same mathematical principles,” says Heesen. Bonobos are known to use some of the same gestures as chimps. “We hope that our work will pave the way for similar studies, to see quite how widespread these laws might be across the animal kingdom,” Heesen says. As well as using hand and foot gestures, chimps communicate with noises, body postures and facial expressions. A study last year found that that chimps and human toddlers use similar stamping, pointing and clapping tactics to get attention.
10-30-18 Orangutans are exceptionally good at keeping their infants alive
Orangutans have staggeringly low rates of infant mortality. They are better at keeping their offspring alive than people in most human societies throughout history. “We see this incredibly high survival that’s higher than any [non-human] mammal that we know of so far,” says Maria van Noordwijk at the University of Zürich in Switzerland. The high survival rate is linked to orangutans’ lifestyle, which is more solitary than other apes. But it also puts them at risk, because it is tied to their low birth rate – meaning they would struggle to recover from a population crash. Van Noordwijk and her colleagues compiled data on births and infant survival from five populations: two groups of Sumatran orangutans and three of Bornean orangutans. There is also a third species, the Tapanuli orangutan described in 2017, but they have not been studied long enough to estimate survival rates. On average, female orangutans give birth once every 7.6 years: among humans, it is typically closer to 3 years. Female orangutans also did not give birth until they were on average 14-15 years old. Infants had a very good chance of surviving. Overall 91 per cent survived until they were weaned. Breaking the data down by gender, the researchers discovered that 94 per cent of females survived into adulthood and gave birth themselves. The data were less reliable for males, which roam after weaning and so are harder to track. This is a better survival rate than any other great ape, and is also better than African elephants and even a group of human hunter-gatherers. Children do have a higher survival rate in some populations, such as in modern Switzerland, but not all countries achieve the orangutan’s infant survival rate.
7-30-18 Anxiety in monkeys is linked to hereditary brain traits
Brain activity patterns tied to anxiety get passed down from parent to offspring. Anxiety can run in families. Key differences in how an anxious monkey’s brain operates can be passed along too, a large study suggests. By finding a pattern of brain activity linked to anxiety, and by tracing it through generations of monkeys, the results bring researchers closer to understanding the brain characteristics involved in severe anxiety — and how these characteristics can be inherited. “We can trace how anxiety falls through the family tree,” which parents pass it on to which children, how cousins are affected and so on, says study coauthor Ned Kalin of the University of Wisconsin School of Medicine and Public Health in Madison. The newly identified brain activity pattern takes the same path through the family tree as the anxious behavior, Kalin and colleagues report July 30 in the Journal of Neuroscience. Kalin and colleagues studied rhesus monkeys that, as youngsters, displayed an anxious temperament. Human children with this trait are often painfully shy, and are at much higher risk of going on to develop anxiety and depression than other children, studies have shown. Monkeys can behave similarly. Researchers measured anxious temperament by subjecting young monkeys to a stressful situation: An intruder entered their cage and showed only his or her profile to the monkey. “The monkey isn’t sure what is going to happen, because it can’t see the individual’s eyes,” Kalin says. Faced with this potential threat, monkeys freeze and fall silent. By measuring the degree of this response, as well as levels of the stress hormone cortisol, the researchers figured out which monkeys had anxious temperaments.
7-26-18 Many chimps are active at night but we don’t know what they do
A study of 22 chimpanzee sites has found that they regularly wake up and move around in the night, but it’s not clear what the apes are up to. The chimps are up to something. A massive study has found that the majority of chimp populations are sometimes active at night but cannot tell us why. Chimps’ nocturnal behaviours have barely been studied, says Maureen McCarthy of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. “Researchers in the field follow them from the time they get out of their nest in the morning to the time they nest around twilight hours,” she says. “What happens between the time they nest in the evening and the following morning has largely been a mystery.” However, in 2014 it emerged that chimps in Uganda raid farmers’ crops at night. McCarthy is part of a research team that compiled data from 22 chimp research sites in Africa. They used ground-based camera traps to see what the chimps did at night. The camera traps spotted chimps out and about at night at 18 of the 22 sites. It happened at all hours of the night but was most common at twilight. In most cases, the chimps were simply snapped moving past the camera. “We don’t know what they were doing,” says McCarthy. “It could be they were travelling to feeding sites and feeding in the night, or it could be they were changing from one nest location to another.” It may be significant that lone males were the most frequently observed. “It could be males either doing patrolling behaviours, or seeking out mating opportunities.” In total about 2 per cent of the chimps’ recorded activity took place at night, but McCarthy says it could be much more. For one thing, the camera traps will have missed any activity up in the trees.
7-2-18 Some monkeys in Panama may have just stumbled into the Stone Age
One group of capuchins uses stone tools, but neighbouring groups do not – suggesting primates - including us - might enter the Stone Age simply by chance. Another non-human primate has entered the Stone Age – the fourth type known to have done so. One population of white-faced capuchins living in Panama routinely use stones to smash open nuts and shellfish. Other nearby populations don’t make use of stone tools, which might suggest that primates – perhaps including our ancestors – stumble into the stone age by chance. Chimpanzees in west Africa, macaques in Thailand and several species of tufted, strongly built capuchin monkeys living in South America use stone tools to access food. Brendan Barrett at the Max Planck Institute for Ornithology in Radolfzell, Germany, and his colleagues have now discovered that a species of non-tufted, slender-bodied capuchin monkey also uses stone tools. The tufted and non-tufted capuchins are estimated to have split from each other about 6.2 million years ago, says Barrett. “That’s a similar divergence time between our lineage and the last common ancestor of chimpanzees and bonobos,” he says. In other words, he says, the non-tufted capuchins are the fourth distinct type of non-human primate known to use stone tools on a regular basis. It’s an exciting discovery, according to both Dorothy Fragaszy at the University of Georgia in Athens and Patrícia Izar at the University of Sao Paulo, Brazil. “It reinforces our suspicions that we have interesting things to discover about even well-studied species by looking at populations in new places,” says Fragaszy.
6-29-18 A gorilla who spoke to humanity
Millions of people are mourning a gorilla, “and that’s a good sign for humanity,” said Molly Roberts. Koko, a western lowland gorilla who died last week at age 46, became a superstar for learning a version of American Sign Language. The subject of countless articles and documentaries, she could comprehend 2,000 words and “speak” 1,000. Over the years, skeptics questioned how much of her communication was rooted in “our own preconceptions and projections.” They pointed out that Koko occasionally made the wrong sign, and that her caretaker’s questions sometimes seemed “designed to elicit responses that made it seem as if Koko understood more than she really did.” But “boy, did we want to believe.” When Koko watched a sad movie, “her eyes watered.” When her kitten was killed by a car, Koko reacted with unmistakable anguish, signing “bad, sad, bad” and “frown, cry, frown.” She tickled Robin Williams and cuddled with Fred Rogers. Those who met Koko “almost all say they felt something.” Science is still far from establishing how much apes truly resemble humans mentally and emotionally, but in Koko’s case, it “may not really matter.” What mattered is that we looked at this creature, and “somewhere in Koko’s eyes, we saw ourselves.”
6-22-18 Koko the gorilla is gone, but she left a legacy
When Koko died in her sleep in California on June 19, people throughout the world immediately began mourning the gorilla. Koko was a charmer and undeniably smart. She took an unusual route to fame. Stanford University graduate student Francine Patterson started teaching Koko a version of sign language in 1972, the year after the infant ape was born. Patterson rapidly developed a deep emotional connection to Koko. Patterson’s claims that Koko learned to communicate and converse with sign language in a humanlike way won the gorilla legions of fans but also attracted much scientific criticism. Patterson’s work with Koko came at a time when captive chimps were also receiving sign language training. Science News spoke with anthropologist Barbara King about Koko’s legacy. King, of the College of William and Mary in Williamsburg, Va., studies emotions and thinking in nonhuman animals. Her books include How Animals Grieve.
- What were your first thoughts upon hearing that Koko had died?
- What is Koko’s scientific legacy, especially for understanding ape communication?
- Did Francine Patterson get too close to Koko to perform credible studies?
- How do you explain Koko’s broad and lasting cultural appeal?
- Should scientists pursue new sign language studies in apes like those conducted with Koko?
5-30-18 Mystery ghost ape species found hidden in bonobo’s genome
A comparison of chimpanzee genomes has found signs that a previously unknown species of chimpanzee once lived in the forests of central Africa. THE great ape family is about to welcome a new member. A comparison of genomes has found signs that a previously unknown species of chimpanzee once lived in the forests of central Africa. As far as we know, there are no physical remains of the ancient ape. We only know about it because it mated and had offspring with bonobos – a chimp species – roughly 400,000 years ago, and its genes persist in living apes today. It is what is known as a ghost species. Traditionally, it was thought that species were groups of organisms that would not produce “viable” offspring – ones capable of having babies – with any other group. But we now know that is not the case. Grizzly bears and polar bears, for instance, have begun mating as climate change squeezes their ranges together. Many other species have mated over the years. Genetic studies are revealing that “impossible” relations once happened with previously unknown extinct animals. When researchers compared the genomes of common chimps and bonobos, they found evidence that the two species had once interbred (see “Friends with benefits”), much like humans and Neanderthals once did. Martin Kuhlwilm at the Institute of Evolutionary Biology in Barcelona, Spain, went one step further by comparing the genomes of 59 wild chimpanzees and 10 wild bonobos. In each species, he looked for unusual DNA: fragments that could neither be explained by ancient matings with the other species, nor by random mutations. That DNA, he reasoned, had to have another origin altogether, a ghost source. This statistical method has previously been used to identify extinct human species.
5-24-18 Pregnant bonobos get a little delivery help from their friends
Observations of captive apes suggest they, like humans, have ‘social’ births. Like humans, African apes called bonobos may treat birth as a social event with a serious purpose. In three recorded instances in captivity, female bonobos stood close by and provided protection and support to a bonobo giving birth to a healthy infant. Female bystanders also gestured as if ready to hold an infant before it was born, or actually held one as it was born, scientists report online May 9 in Evolution and Human Behavior. Ethologist Elisa Demuru of the Natural History Museum of the University of Pisa in Italy and colleagues filmed these incidents in 2009, 2012 and 2014 at two European primate parks where the apes roam freely through forested areas. These observations, along with a 2014 report of wild bonobos behaving similarly, challenge an influential idea that human females, unlike other primates, receive birth assistance. Scientists had proposed that the perils of passing a baby through the relatively narrow human birth canal called for help from others. But bonobos can safely give birth on their own, so something else is at work here, Demuru and colleagues suspect. Comparably high levels of sociability among female bonobos and among women may instead explain why helpers assemble as a pregnant individual nears delivery. Chimpanzees, close cousins of bonobos, are a different story. Female chimps are more competitive and maintain weaker social bonds than female bonobos or humans do. No chimps have been spotted helping or hanging out near a peer about to give birth.
5-24-18 Chimp evolution was shaped by sex with their bonobo relatives
Some chimpanzee populations gained useful DNA from interbreeding with bonobos, and one may even have become more gentle and “bonobo-like” in its brain structure and behaviour. Humans and chimpanzees might have one more thing in common: they both seem to have benefitted from sex with a closely related species. During the last decade, geneticists have reported that our species interbred with ancient humans including the Neanderthals and Denisovans. They have also found tantalising signs that we benefitted from doing so, gaining DNA that may have boosted our immune systems or made us better able to survive at high altitude or in the frigid Arctic. Now comes evidence that something similar has been going on in chimpanzees, following episodes of interbreeding with their close relatives bonobos during the last 500,000 years. Three of the four subspecies of chimpanzee carry sections of bonobo DNA in their genomes. This prompted Jessica Nye at Pompeu Fabra University in Barcelona, Spain and her colleagues to investigate whether the bonobo DNA has benefitted the chimps. It seems it has. Certain chunks of bonobo DNA are unusually common in chimp populations, suggesting they have spread because they are useful. Different segments of bonobo DNA seem to have been favoured in the different chimp subspecies. That’s a surprise, says Nye. It suggests there is a complex interplay between genetics and the environment each chimp subspecies occupies, meaning each subspecies has gained in a unique way from the bonobo DNA.
5-18-18 Ape ‘midwives’ spotted helping female bonobos give birth
When female bonobos went into labour, other females gathered around to keep them safe, swatting away flies and even seemingly trying to catch the baby as it emerged. When bonobos give birth, other females gather around to support and protect the mother. These “midwives” bely the notion that assistance during birth is unique to humans. Until now there has only been one scientific account of a wild bonobo giving birth, published in 2014. On that occasion, other females stayed close to the mother. Now Elisa Demuru of the University of Pisa in Italy and her colleagues have described three births among captive bonobos at primate parks in France and the Netherlands. On each occasion, the mother made no attempt to isolate herself from the group. Other females showed a keen interest in the mother, inspecting her genital area and sniffing the birth fluid. Some placed their hands under her, as if trying to grab the baby as it emerged. One was seen swatting away flies. Some of these companion females had given birth before, and their behaviour suggested they knew what was going on, says Demuru, who is now based at the French National Center for Scientific Research in Paris. The companions were protective towards the mother, keeping males and the human observers away. “We believe they want to show the female that they are there to support and protect her in the phase in which she’s most vulnerable,” says Demuru. The females in a bonobo group are usually not related. However, they form close bonds, helping them to assert dominance over males. This is a stark contrast with chimpanzees, bonobos’ closest living relatives, in which females tend to be more solitary and competitive. Female chimpanzees tend to give birth in isolation.
5-4-18 Bonobos barely use their opposable thumbs when climbing trees
Apes and humans are famed for their opposable thumbs, but our close cousins the bonobos regularly swing through trees without using their thumbs. An opposable thumb is supposed to be a sign of a sophisticated species. But apes called bonobos make little use of their thumbs when they hang from tree branches – even though we use ours to keep a tight grip. Bonobos are our closest living relatives, along with chimpanzees. We are all descended from the same common ancestor, so studying bonobos can give us clues to what that common ancestor was like. Tracy Kivell at the University of Kent, UK and her colleagues studied bonobos living at Planckendael, a zoo in Antwerp, Belgium. The team wrapped a pressure-sensing mat around a wooden beam in the bonobos’ enclosure, and recorded the apes’ behaviour with a high-speed camera. At different times, the mat was on horizontal or vertical beams, which the bonobos used in different ways such as knuckle-walking or hanging by their fingers. The parts of the mat touched by the bonobos’ thumbs recorded extremely low pressures, or no pressure whatsoever. “We were a bit surprised that, even though it’s clear from the video that the thumb is fully contacting the pole, there’s very little pressure there,” says Kivell. The bonobos may simply use their thumbs to guide the rest of the hand into place, she suggests. In an unpublished study, one of Kivell’s students tried a similar experiment with human subjects. As expected, the thumb pressure readings were much higher.
4-17-18 Baboons prop up barrels to escape Texas research centre
Officials at Texas research centre have made changes to the enclosures after four baboons leapt to freedom. The primates propped up barrels against the walls of their yard at the Texas Biomedical Research Institute and used them to jump over the fence. Three baboons then escaped the centre perimeter, while the fourth returned to its pen on its own. All three of the escapees were captured within half an hour. There are about 1,100 baboons in the facility. The San Antonio institute issued a press release detailing the escape and the animals' recapture. According to the statement, the baboons rolled a 55-gallon barrel up against the wall of their open-air yard to escape. The enclosure at the Southwest National Primate Research Center (SNPRC) - part of the research institute - has been in use for 35 years. Researchers gave the baboons the barrels as an "enrichment tool", to help them mimic foraging as they would in the wild. Staff immediately removed the barrels once they realised the primates had used them to jump the walls. (Webmaster's comment: So much for the "stupid animals" believers! The baboons figured out how to get out!)
3-26-18 Modern chimp brains share similarities with ancient hominids
Scans suggest certain folding patterns don’t mark humanlike neural advances after all. Groove patterns on the surface of modern chimpanzee brains throw a monkey wrench into proposals that some ancient southern African hominids evolved humanlike brain characteristics, a new study suggests. MRIs of eight living chimps reveal substantial variability in the shape and location of certain features on the brain surface. Some of these brains showed surface creases similar to ones that were thought to have signaled a turn toward humanlike brain organization in ancient hominids hundreds of thousands, if not millions, of years ago. Paleoanthropologist Dean Falk of Florida State University in Tallahassee and colleagues report their findings online March 13 in Brain, Behavior and Evolution. The study casts doubt on a 2014 paper by Falk that was based on casts of the inside of fossil braincases, called endocasts, which preserve impressions of these surface features. At the time, Falk argued that four endocasts from southern African hominids — three Australopithecus africanus and one Australopithecus sediba — showed folding patterns that suggested that brain reorganization was underway as early as 3 million years ago in a frontal area involved in human speech production. But MRIs of three of the chimp brains reveal comparable creases, the researchers found. Two other chimps display other frontal tissue furrows that Falk had also previously described as distinctly humanlike.
2-27-18 Our cousins chimps and bonobos use similar sign languages
Despite diverging a million years ago, chimps and bonobos use a very similar sign language, suggesting the meanings of their gestures may have a biological basis. An analysis of chimpanzee and bonobo gestures suggests that if the two apes ever come face to face, they would probably be able to understand each other. Kirsty Graham, of the University of York, UK, and her team determined the meaning of 33 different gestures made by bonobos, and compared them with those made by chimpanzees. The two species diverged from each other at least a million years ago, but the team found that the their gestures are more similar than would be expected by chance. “Bonobos and chimpanzees share not only the physical form of the gestures, but also many gesture meanings,” they say. This may suggest that primate gestures are at least partially determined by biology. The team plans to investigate whether humans also share some of these gestures. While chimpanzee gestures have been well studied, less is known about those of bonobos. The team determined the meaning of each of the gestures by observing the reactions they produced in other individuals.
2-27-18 Advertising campaign for monkeys uses sex to sell brands
Everyone knows that in advertising sex sells, and it turns out that sex-themed adverts even work on rhesus macaques. Sex sells. It’s rule one in the book of advertising. So when scientists set out to create an advertising campaign for monkeys, they didn’t stray far from the basics. Social primates like monkeys value information about status in the group hierarchy, and about each others’ sexual receptivity. Indeed primates – both human and non-human – will forego rewards to view images of the genitals of their species. But could this lascivious interest be harnessed in an ad campaign for monkeys? To find out, Yavuz Acikalin at Stanford University in California and his colleagues enlisted ten rhesus macaques, five of each sex. “We thought it would be fun to look at this issue in the advertising paradigm,” he says. The monkeys were shown an image of a real-world brand logo – say, Pizza Hut – alongside an image of a monkey. This was the “advert”. There were three kinds of images in adverts: a dominant male’s face, a subordinate male’s, or a female monkey’s bare bottom and exposed genitalia. Later, the monkeys were shown the logo from the advert, alongside a new logo such as Domino’s. They chose which logo they liked best by tapping a touchscreen. Each monkey completed three sessions, each including 70 adverts and 90 choices. The animals preferred brand logos they had seen previously in adverts. While the sample size is small, the results suggest advertising works on monkeys.
1-31-18 Primate archaeology: Digging up secrets of the monkey Stone Age
The discovery that chimps and some monkeys have a long history of making tools is forcing us to rethink our own cultural evolution A CASHEW is a tough nut to crack. You must carefully balance it on an anvil and bash it with a hammer, while avoiding contact with the caustic resin in its shell. This takes great skill. Yet bearded capuchin monkeys living in north-east Brazil take it in their stride. And their tool-wielding talents don’t end there. They also dig for tubers and insects with rocks. Females sometimes even hurl them at males in what appears to be an unusual flirting tactic. We used to think that using tools was the preserve of our hominin linage and one of the remarkable talents that made us human. So much for that idea… In fact, we have known for some years that our closest living relatives, chimps, employ a variety of tools, including some made of stone. Recently, primatologists have been intrigued to discover that this also applies to two more-distant cousins – the capuchins and macaques living in a coastal region of Thailand. The findings have attracted the attention of archaeologists keen to explore the so-called Stone Ages of non-human primates. Digging through layers of dirt, they have already unearthed the remains of tools made thousands of years ago. Their discoveries usher in the new discipline of primate archaeology, which has the potential to give novel insights not just about these species but also about our distant ancestors.
1-25-18 Chimps are now dying of the common cold and they are all at risk
The deaths of five Ugandan chimpanzees have been traced to a human cold virus, and DNA tests suggest all African chimps are vulnerable . As if poaching, logging, habitat loss and climate change aren’t bad enough, wild chimpanzees now face a new, deadly peril: a virus that causes common colds in people. The threat has been exposed after an investigation of an outbreak of respiratory disease that struck chimps in 2013. The outbreak occurred in the Kanyawara community in Uganda’s Kibale National Park. Out of 56 chimpanzees, five died: almost 10 per cent of the population. A detailed post mortem on a two-year-old chimp called Betty, who died of severe pneumonia, demonstrated almost beyond doubt that human rhinovirus C was to blame. Genes from human rhinovirus C were found throughout Betty’s fluid-filled lungs and respiratory tract. No other viruses or infectious agents were detected. “It was the smoking gun in that animal, a virus that shouldn’t be there, and no others,” says lead author Tony Goldberg of the University of Wisconsin-Madison. “We think this human common cold virus represents a grave threat to chimpanzees all across Africa.” Unlike cold rhinoviruses A and B, rhinovirus C poses a special threat because it evolved relatively recently in humans. It caused widespread infant mortality from around 8000 years ago, when the rise of farming drove people to live closer together. Half the human population now has immunity to rhinovirus C. However, many still carry a variant of the CDHR3 gene that makes them especially susceptible, intensifying symptoms and raising the risk of childhood asthma.
1-17-18 All other primates live their lives according to a simple rule
Hundreds of species of primate all form groups of the same five sizes, suggesting that the ecosystems in which they live strongly shape their lifestyle. A SIMPLE rule governs a seemingly random phenomenon: the sizes of the groups in which primates live. It seems our closest living relatives opt for social groupings that aren’t as varied and flexible as you might think. Susanne Shultz at the University of Manchester, UK, and her colleagues compared group sizes in 215 primate species. The average number in a group varied between species but was always clustered around five distinct sizes (Biology Letters, DOI: 10.1098/rsbl.2017.0490). The preferred group sizes were, roughly: 2.5, 5, 15, 30 and 50. The smallest normally had two adults and some offspring. Bigger ones tended to be either a single male with many females, or multiple males and females. Other patterns, such as lots of males and few females, were rare. “The other thing that seems to be hard for primates to do is male and female pairs combined in a group,” says Shultz, even though this is common in birds. Primates reuse these strategies because they keep facing the same challenges, Shultz says. “Ecology and social relationships are tightly interconnected.” For instance, species occupying open ground form the largest groups, perhaps to defend against predators. Those that live in trees in dense forests prefer medium groups, as big groups would be impossible to coordinate. In 2011, Shultz showed that primate group sizes also evolved in leaps (Nature, doi.org/bpnncg).
1-5-18 ‘Laid-back’ bonobos take a shine to belligerents
Cozying up to unhelpful peers, not cooperators, may motivate these apes. Despite a reputation as mellow apes, bonobos have a thing for bad guys. Rather than latching on to individuals with a track record of helpfulness, adult bonobos favor obstructionists who keep others from getting what they want. The result may help explain what differentiates humans’ cooperative skills from those of other apes, biological anthropologists Christopher Krupenye of the University of St. Andrews in Scotland and Brian Hare of Duke University report online January 4 in Current Biology. Previous investigations indicate that, by 3 months old, humans do the opposite of bonobos, choosing to align more frequently with helpers than hinderers. Humans, unlike other apes, have evolved to seek cooperative partnerships that make large-scale collaborations possible (SN: 10/28/17, p. 7), Krupenye and Hare propose.
12-18-17 What chimpanzees on the hunt can tell us about human behavior
In the early 1960s, scientists started to follow Jane Goodall into the east African forest to study apes in the wild. As research findings accumulated it became evident that chimpanzees left to pursue their own lives had a lot to teach us about what it means to be human. Craig Stanford, a professor of biological sciences and anthropology at the University of Southern California, has dedicated his career — which began with Goodall in the Gombe region of Africa — researching chimps, documenting their habits, and pondering the nature of this connection. His forthcoming book, The New Chimpanzee: A Twenty-First-Century Portrait of Our Closest Kin, offers deeply informed (and admirably accessible) insight into what chimps can tell us about a compendium of human pursuits, ranging from sex, politics, violence, and family to self-care, alpha maleness, social cooperation, and status. But the one area where the book especially shines is on the topic that's been the main focus of Stanford's work for decades: hunting and eating meat. It was long thought that chimpanzees were vegan. When Goodall, in the early 1960s, reported a supposedly herbivore chimp devouring a baby bushpig, her colleagues reacted with skepticism. Many of them flat out claimed that she was wrong. "Not until hunting was seen in numerous other forests," Stanford writes, "did the entire scientific community accept that meat eating is a core aspect of chimpanzee behavior." Stanford now considers hunting "one of the cultural traditions intrinsic to chimpanzee life." And chimps, he reiterates, are omnivores in the same way humans are.
12-15-17 Young female monkeys use deer as ‘outlet for sexual frustration’
Adolescent female Japanese macaques mount deer and rub on their backs, perhaps as a way to practise sexual behaviour before they are old enough to mate. Just monkeying around? Adolescent female monkeys mount deer and rub themselves on the deers’ backs, apparently to practise sex when they are too young to be chosen by adult males. Earlier this year, researchers reported observations of a single male Japanese macaque mounting sika deer and trying to mate with them. In Minoo, Japan, researchers started recording monkey-deer liaisons in 2014, but there, it’s female macaques that have been observed mounting the deer. Noëlle Gunst and colleagues at the University of Lethbridge, Canada, recorded five adolescent female macaques mounting deer a total of 258 times in a two month period. In the same group of monkeys, adolescent females are sometimes seen mounting other females or males and soliciting them for sex. These relationships, known as consortships, are thought to be a way to practise and develop adult sexual behaviours. Gunst even claims the female monkeys experience sexual reward through genital stimulation by mounting other monkeys. Gunst believes the deer-mounting behaviour is related. It has only been seen during the mating season and her observations show that the form and frequency of monkey-deer interactions are similar to their consortships with other monkeys.
12-4-17 Macho, macho monkey: female monkeys gaze more at masculine faces
Female monkeys spend more time staring at males that have highly masculine facial features, but we don’t know if they fancy them or fear them. Female monkeys spend more time staring at males with strong masculine facial features. But it’s not clear why their gaze lingers like this. Face structure often varies between male and female members of a species. In humans, men tend to have heavier brows, squarer jaws, deeper-set eyes and thinner lips than women. Some researchers believe that facial masculinity signals mate quality, but this is hotly contested. To find out, Kevin Rosenfield, who was at Roehampton University in the UK when the study was performed, and his colleagues examined facial preference in monkeys. They studied 107 free-ranging female rhesus macaques on the island of Cayo Santiago in Puerto Rico. Each female was simultaneously shown two photos of male faces, one of which was more masculine than the other. Masculine features included bigger jaws, longer noses, and smaller eyes. When the two faces had similar levels of masculinity, the females spent equal time observing them. But when the differences were more obvious, they spent an average of 1.9 seconds staring at the more masculine face, compared to 1.5s looking at the less masculine one. They may have been attracted to them, perhaps because they associated them with better genes. Alternatively, they may have been scared of them because they associated them with aggression. (Webmaster's comment: The same happens in human females. The more of a brute he is the better his genes are for making offspring that will survive.)
11-13-17 Monkeys learn to play ‘chicken’ in a virtual driving game
Macaque monkeys have been trained to play a computer version of “chicken”, driving virtual cards towards each other to see who flinches first. Monkeys have something in common with daredevil teenagers: an aptitude for the potentially deadly car driving contest, “chicken”. In the human version of the game, two people drive their cars towards each other down a long, straight road. Whoever turns aside first is the chicken; if neither does, there’s a head-on crash. Four macaques were trained to play a version of this nerve-testing game on a computer, getting rewards of fruit juice if they avoid a crash. They were given the most juice if they were the one who didn’t give up and swerve. In parallels with human social mores, more submissive monkeys were more likely to swerve. “Hierarchy really matters,” says Wei Song Ong, of the University of Pennsylvania. “It’s a bit like James Dean.” Pairs of macaques played the game while sitting across from each other at a table-top computer screen, using joysticks to control their cars. As well as watching the progress of their cars on the screen below, Ong’s team found that the monkeys often looked at each other’s eyes. Monkeys that were about to yield tended to look to the side of the screen, where their car was about to veer off – information that could be exploited by their partner to avoid yielding if the other is about to. “If one monkey sees the other is looking at the swerve target, we think they are attributing intention to that,” says Ong.
11-10-17 Watch a monkey floss its teeth with a bird feather
Nicobar long-tailed macaques have learned to use an array of tools, from wrapping prickly food in leaves to avoid getting hurt, to using bird feathers to floss their teeth. Monkeys living on an island have learned to use a startling variety of tools and techniques to obtain the juicy innards of different foods – and to floss their teeth afterwards. The Nicobar long-tailed macaque (Macaca fascicularis umbrosus) is only found on three islands in the eastern Indian Ocean. One of them is Great Nicobar Island. To find out about the macaques’ eating habits, Honnavalli Kumara at the Sálim Ali Centre for Ornithology and Natural History in Coimbatore, India, and colleagues followed 20 around a small coastal village on the island. Many of the macaques’ favoured foods are thorny, slimy, hairy or mucky. To get rid of these inedible coatings, the macaques either wash the foods in puddles or wrap them in leaves and rub them clean. They also wrap leaves around certain foods to make them easier to hold. Trash like paper, cloth or plastic is also used for wrapping and wiping foods. The macaques eat coconuts too, plucking them from the tree by twisting them around or using their teeth to cut them off. If it is tender, the macaques de-husk the coconut using their teeth, holding it down with their feet and hands, in order to get to the water and juicy bits inside. If the coconut is ripe, however, they also have to crack its shell. To do so, they take it to a hard surface like a rock or concrete, and pound it. It’s not just tool use. The macaques were seen beating bushes with their hands to disturb insects hiding within, catching those that fly out or drop to the ground.
10-13-17 Male chimpanzee seen snatching seconds-old chimp and eating it
Male chimpanzee seen snatching seconds-old chimp and eating it
A rare sighting of a chimpanzee birth ended in infanticide and cannibalism – and probably explains why new mothers often go into hiding for weeks or months. A rare sighting of a chimpanzee giving birth in the wild came to a grisly conclusion. Within seconds of the birth, the baby was snatched away and eaten by a male of the same group. The observation explains why female chimpanzees tend to go into hiding for weeks or months when they have their babies. Little is known about how chimpanzees give birth in the wild because only five births have ever been observed, says Hitonaru Nishie of Kyoto University in Japan. Nishie and his colleagues have been studying chimpanzees in Tanzania’s Mahale mountains for the last few years. One of the reasons so few have been witnessed is that the soon-to-be mothers often leave the group when the baby is due, and don’t return until the infant is weeks or months old. This absence has been described as a chimpanzee’s “maternity leave”. So Nishie and his colleague Michio Nakamura were surprised when, at around 11 am one December day, a female member of the chimpanzee group they were observing began to give birth in front of the 20 other members. As soon as the baby was out – and before the mother had even had a chance to touch it – the baby was snatched away by a male member of the group, who then disappeared into the bush. The researchers found him around 1½ hours later, sitting up a tree and eating the infant from the lower half of its body. He ate the entire body within an hour. This is the first time anyone has reported seeing a newborn chimpanzee cannibalised in this way, says Nishie. He says that his observation provides an obvious clue as to why chimpanzee mothers tend to hide away to give birth.
9-19-17 Tool-wielding monkeys push local shellfish to edge of extinction
Tool-wielding monkeys push local shellfish to edge of extinction
Long-tailed macaques on an island in Thailand are doing such a good job of cracking shellfish with stone tools, they are driving down their prey's numbers and body size. HUMANS aren’t the only primate to have pushed their prey towards extinction. Monkeys have also over-exploited animals for food. Long-tailed macaques forage for shellfish on islands off Thailand, then crack them open with stone tools. They target the largest rock oysters, bludgeoning them with stone hammers, and pry open the meatiest snail and crab shells with the flattened edges of their tools. These macaques are one of three primates that use stone tools, alongside chimpanzees in Africa and bearded capuchins in South America. “Stone tools open up an opportunity for foods they otherwise wouldn’t even be able to harvest,” says Lydia Luncz at the University of Oxford. Luncz wanted to investigate the impact of the monkeys’ shellfish snacking on the prey themselves. Her team followed 18 macaques on their daily foraging routes along the shores of Koram and NomSao, two neighbouring islands off eastern Thailand, recording their tool selection and use. On Koram – the more densely populated island, home to 80 macaques compared with NomSao’s nine – Luncz’s group saw not only smaller oysters and snails, but also fewer of each species. Multiple prey species were less abundant on Koram than NomSao, with four times as many tropical periwinkles on NomSao as on Koram (eLife, doi.org/cc7d). “It’s been shown that systematic predation causes prey of smaller size,” says Nathaniel Dominy at Dartmouth College in Hanover, New Hampshire. The oysters on Koram were about 70 per cent smaller than their counterparts on NomSao, and the periwinkles were less than half the size. A single tool-using monkey on Koram can eat over 40 shellfish a day, so Luncz’s group thinks this predation pressure is driving these shellfish changes.
9-4-17 It took these monkeys just 13 years to learn how to crack nuts
It took these monkeys just 13 years to learn how to crack nuts
The long-tailed macaques of Thailand already used stone hammers to split open shellfish, and now they have worked out how to use them to crack open nuts. The macaques of southern Thailand have started a new tradition. For at least a century, they have used simple stone tools to smash open shellfish on the seashore. Now the monkeys have begun using stones to crack open oil palm nuts further inland. The finding means they may be the first non-human primates to have begun adapting their Stone Age technology to exploit a new ecological niche. Tool use is common in the animal kingdom, but very few animals make routine use of stones as tools. Among non-human primates, just three species are known to do so: the western chimpanzees of West Africa, the bearded capuchins of Brazil and the long-tailed macaques of Thailand. However, in all three cases biologists thought the primates restricted their stone tool use to a specific environmental setting. “The chimpanzees live in tropical rainforest, and the capuchins in a dry savannah area,” says Lydia Luncz at the University of Oxford. And the macaques spend a lot of time on the beaches of Thailand’s islands, where they use stones to break into shellfish. But the macaques also roam inland. In 2016, Luncz and her colleagues trekked through Yao Noi Island into an abandoned oil palm plantation. They found what appeared to be stones that had been used as hammers and anvils associated with broken oil palm nuts.
8-26-17 Low-ranked female monkeys band together against their leaders
Low-ranked female monkeys band together against their leaders
Female rhesus macaques have a strict hierarchy, but the subordinates can buck authority and even climb the social ladder if they’re big enough and have enough friends. If you’re trying to overthrow the boss, you might need a friend to back you up. The same is true for female macaques, who need allies to resist authority and take down more powerful members of the group. Most primates have social hierarchies in which some individuals are dominant over the others. For rhesus macaques, these strict hierarchies are organised around female relationships. Lower-ranked females have little social mobility and must silently bare their teeth to higher-ranked females. The signal means “I want you to know that I know that you out-rank me” and is important in communicating social rank, says Darcy Hannibal at the University of California, Davis. “They are ‘bending the knee’.” But Hannibal and her colleagues have discovered that subordinate females can override the status quo. To do this, female macaques form alliances with family, friends or both. These alliances help females maintain or increase their social rank and compete for resources. A female who wants to challenge those higher up needs this help, says Hannibal. To find out what factors affect the rate of insubordination, the team studied 357 captive adult females, who experienced almost 11,000 conflicts. Insubordination events were more likely if the lower-ranked female was older. They were most likely if the subordinate outweighed the dominant female by 7 kilograms and the dominant female had no family allies. The more allies the subordinate female had, and the more days her mother was present in the group, the more often she would exhibit insubordinate behaviour.
8-18-17 Grown-up chimps are less likely to help distressed friends
Grown-up chimps are less likely to help distressed friends
Chimpanzees of all ages will comfort upset companions, but adult chimps do it less – perhaps because they are more selective about who they help. There, there! Adult chimpanzees are less likely than younger ones to console their companions in times of distress. The finding raises questions about how the capacity for empathy changes with age in our closest relatives – and us. When a chimpanzee gets upset, perhaps after losing a fight, companions will often sit with them and provide reassurance by kissing, grooming or embracing them. The same is true of young children. By age 2, children typically respond to a family member crying by consoling them in a similar way. We know chimpanzees have personalities: individual differences in their behaviour that are consistent over time. But it was unclear whether their empathetic tendencies are part of their personality, and whether they change over time. Christine Webb at Emory University in Atlanta, Georgia, and her colleagues wanted to find out. The team studied eight years of observations of a group of 44 chimpanzees at Yerkes National Primate Research Center, also in Georgia. They found that individual differences were consistent over their lifespan: chimps who consoled more in their youth, relative to their peers, also consoled more than their peers later in life. This is the first evidence that chimps have “empathetic personalities”, says Webb. But they also found that juvenile chimpanzees console others more than adults, and infants console most of all age groups.
8-16-17 Chimps can play rock-paper-scissors
Chimps can play rock-paper-scissors
Japanese researchers have taught chimps the rules of rock-paper-scissors.
8-10-17 Primate brains react differently to faces of friends and VIPs
Primate brains react differently to faces of friends and VIPs
Two newly identified brain areas reveal how rhesus macaques recognise the difference between intimately familiar faces and faces that the monkeys know less well. Two newly identified brain areas in rhesus monkeys seem to help the animals recognise familiar faces. Primates, Homo sapiens included, must be able to differentiate between faces and recognise friend from foe because social hierarchies play a large role in daily life. But exactly how primate brains deal with faces is not completely clear. One idea is that the same parts of the brain are involved in recognising both familiar and unfamiliar faces, just with varying efficiency. But Sofia Landi and Winrich Freiwald at Rockefeller University in New York have now cast doubt on that thinking. Their work shows that distinct brain areas are responsible for recognising the primates you know. Many researchers have already shown that certain areas of the temporal and prefrontal cortex are involved in unfamiliar face perception in rhesus monkey brains. Using whole-brain fMRI scans of four monkeys, Landi and Freiwald have now identified two additional brain areas that play a role not only in unfamiliar face perception but also in recognising familiar faces. The two new areas are in the anterior temporal lobe – the part of our brains above and in front of our ears. One is in the perirhinal cortex and one is in the temporal pole. These regions lit up far more when the monkeys recognised a familiar face in a photograph, as opposed to when they were presented with images of a stranger.
8-8-17 Chantek, the orangutan who used sign language, dies at 39
Chantek, the orangutan who used sign language, dies at 39
An orangutan who was one of the first apes to learn sign language has died in Atlanta, Georgia, aged 39. Chantek lived with an anthropologist in Tennessee for about nine years and learned to clean his room, make and use tools and memorise the route to a fast-food restaurant. He spent his later years in Zoo Atlanta where he was treated for heart disease. Zoo officials said he had "an engaging personality" and would be deeply missed. In a statement, Zoo Atlanta said that at 39, Chantek was one of the oldest male orangutans in North American zoos. His cause of death was not yet known, it said, but vets had been treating him for progressive heart disease. Orangutans are considered geriatric after the age of about 35, the zoo added. Chantek was born at the Yerkes National Primate Research Center in Georgia and was sent to live with anthropologist Lyn Miles at the University of Tennessee at Chattanooga. A 2014 documentary called "The Ape Who Went to College" showed that Chantek had learned various skills there including cleaning his room and directing a driving route from the university to a restaurant.
6-29-17 What Nemley Jr's death means for fight to protect chimps
What Nemley Jr's death means for fight to protect chimps
The death of the baby chimpanzee Nemley Jr, rescued from wildlife traffickers only to fade away in a zoo in Ivory Coast, has provoked outrage. And after a BBC investigation that lasted more than a year, those of us involved in the work are finding his loss upsetting and also incredibly frustrating. In the wild, infant chimps have a poor survival record. And youngsters rescued from traffickers have endured the trauma of losing their mothers and then being thrust into the unfamiliar world of humans, so many of them do not make it either. In his last few weeks, Nemley Jr was given intensive care and dedicated support, so who or what is to blame for his shocking demise, and how best to save endangered animals such as chimpanzees from extinction? This long and sad story involves the harsh economics of the black market, the corroding influence of corruption, and the impact on the natural world of the mass consumption of which we are all a part. Add to that an indifference to wildlife among some in West Africa that is bewildering to outsiders, and you have a context in which an infant chimp's chances are slim.
6-26-17 Chimps' strength secrets explained
Chimps' strength secrets explained
The greater strength of chimpanzees, relative to humans, may have been explained by American scientists. A study suggests the difference is mostly due to a higher proportion in chimps of a muscle fibre type involved in powerful, rapid movements. The findings do not support previous work suggesting mechanical aspects of chimp muscles are responsible. But the difference in chimp-human muscle performance is more modest than sometimes depicted in popular culture. In the 1920s, anecdotal evidence along with investigations by the biologist John Bauman, helped feed a perception that chimps were between four and eight times stronger than an adult human. But subsequent studies failed to replicate these figures, as later researchers found that chimps did not greatly outperform adult males when given physical tasks. Writing in PNAS journal, Dr Matthew C O'Neill, from the University of Arizona College of Medicine-Phoenix, and colleagues reviewed the literature on chimp muscle performance and found that, on average, they are 1.5 times more powerful than humans in pulling and jumping tasks.
6-26-17 Chimps are not as superhumanly strong as we thought they were
Chimps are not as superhumanly strong as we thought they were
We sacrificed strength for endurance after our split from other apes, but it turns out our muscles are only a third weaker than those of our ape cousins. Chimpanzees do have stronger muscles than us – but they are not nearly as powerful as many people think. “There’s this idea out there that chimpanzees are superhuman strong,” says Matthew O’Neill at the University of Arizona in Phoenix. Yet his team’s experiments and computer models show that a chimpanzee muscle is only about a third stronger than a human one of the same size. This result matches well with the few tests that have been done, which suggest that when it comes to pulling and jumping, chimps are about 1.5 times as strong as humans relative to their body mass. But because they are lighter than the average person, humans can actually outperform them in absolute terms, say O’Neill. His findings suggest that other apes have similar muscle strength to chimpanzees. “Humans are the odd ones,” he says. O’Neill’s team has been studying the evolution of upright walking. To create an accurate computer model of how chimps walk, the researchers needed to find out whether their muscles really are exceptionally strong. So they removed small samples of leg muscle from three chimps under general anaesthetic and measured the strength of individual fibres. The same procedure is used to study human muscles. Comparing the results with the many studies on those revealed that, contrary to the claims of several other studies, there is nothing special about chimp muscle. “Chimpanzee muscle is really no different than human muscle in terms of the force that individual fibres exert,” says O’Neill.
5-25-17 Monkey mafia steal your stuff, then sell it back for a cracker
Monkey mafia steal your stuff, then sell it back for a cracker
Long-tailed macaques living near an Indonesian temple have learned how to steal human possessions, including cash, and then trade them for food. Long-tailed macaques living near an Indonesian temple have figured out how to run a ransom racket on visiting tourists. The monkeys grab valuables, such as glasses, hats, cameras or, in one case, a wad of cash from the ticket booth, then wait for temple staff to offer them food before dropping their ill-gotten gains and dashing off with the tasty prize. Although this behaviour has been reported anecdotally at Uluwatu Temple on the island of Bali for years, it had never been studied scientifically in the wild. So Fany Brotcorne, a primatologist at the University of Liège in Belgium, and her colleagues set out to discover how and why it has spread through the monkey population. “It’s a unique behaviour. The Uluwatu Temple is the only place in Bali where it’s found,” she says, which suggests it is a learned behaviour rather than an innate ability. Brotcorne wanted to determine whether it was indeed cultural, which could help us better understand the monkey’s cognitive abilities, and even human evolution.
5-17-17 Orangutans take motherhood to extremes, nursing young for more than eight years
Orangutans take motherhood to extremes, nursing young for more than eight years
Weaning has been tricky to observe in the wild, so researchers turned to lab tests. A baby orangutan could guzzle its mom’s milk for more than eight years, the longest of any wild mammal on record. The supermoms of the mammal world are big, shy redheads. Studying growth layers in orangutan teeth shows that mothers can nurse their youngsters for eight-plus years, a record for wild mammals. Teeth from a museum specimen of a young Bornean orangutan (Pongo pygmaeus) don’t show signs of weaning until 8.1 years of age. And a Sumatran orangutan (P. abelii) was still nursing during the few months before it was killed at 8.8 years, researchers report May 17 in Science Advances. Tests also show that youngsters periodically start to taper off their dependence on their mother’s milk and then, perhaps if solid food grows scarce, go back to what looks like an all-mom diet. Such on-again, off-again nursing cycles aren’t known in other wild mammals, says study coauthor Tanya Smith, an evolutionary anthropologist at Griffith University in Nathan, Australia. (Webmaster's comment: Black women in Africa often nurse their children until they are 4 years old. Nursing serves as a prophylactic to help prevent them getting pregnant again.)
4-26-17 Chimps pass on sponge drinking trick like a family tradition
Chimps pass on sponge drinking trick like a family tradition
After a few chimpanzees started using moss to soak up water from a pond, the behaviour has spread. The pattern might tell us about how early human culture spread. Six years ago, a chimpanzee had the bright idea to use moss to soak up water, then drink from it, and seven others soon learned the trick. Three years later, researchers returned to the site to see if the practice had persisted to become part of the local chimp culture. They now report that the technique has continued to spread, and it’s mostly been learned by relatives of the original moss-spongers. This adds to earlier evidence that family ties are the most important routes for culture to spread in animals. After the first report of chimps using moss as a sponge in Budongo Forest, Uganda, researchers rarely saw the behaviour again, and wondered whether chimps still knew how to do it. So they set up an experiment, providing moss and leaves at the clay pit where the chimps had demonstrated the technique before. Then they watched to see whether chimpanzees would use leaves – a more common behaviour – or moss to soak up the mineral-rich water from the pit. Most of the original moss-spongers used moss again during the experiment, and so did another 17 chimps, showing the practice had become more widespread. The researchers wondered what factors influenced which individuals adopted it: were they connected socially, or through families, for instance?
4-5-17 Apes can see things from your perspective and help you out
Apes can see things from your perspective and help you out
Chimps, bonobos and orangutans help humans when they look for objects in the wrong place - showing they can tell when others believe something that's false. Our closest evolutionary relatives are quite the mind readers. And they can use that knowledge to help people figure things out when they are labouring under a misapprehension, according to the latest research. The ability to attribute mental states to others, aka theory of mind, is sometimes considered unique to humans, but evidence is mounting that other animals have some capacity for it. In a study last year, chimps, bonobos and orangutans watched videos of people behaving in different scenarios as cameras tracked their eye movements. The experiment found that the apes looked where an actor in the video would expect to see an object, rather than towards its true location, suggesting the animals were aware others could hold false beliefs. But that experiment left open the possibility apes were simply predicting that the actor would go to the last place he’d seen the object, without understanding that he held a false belief. Now, David Buttelmann at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and colleagues tested 34 zoo chimpanzees, bonobos and orangutans, in search of more conclusive evidence.
3-29-17 Inside knowledge: What’s really going on in the minds of animals
Inside knowledge: What’s really going on in the minds of animals
Bright animals from chimps to crows know what they know and what others are thinking. But when it comes to abstract knowledge, the picture is more mixed. WORKERS at the David Sheldrick Wildlife Trust in Nairobi, Kenya, claim that elephants know they will be looked after at its rescue centre, even if the animals have never been there. Elephants that have had no contact with the centre, but know others who have, often turn up with injuries that need attention. That suggests not only abstract knowledge, but relatively sophisticated communication of that knowledge. Either that, or wishful thinking on our part. The extent to which non-human animals “know” things is difficult to assess. The attribute known as “theory of mind” – the ability to know what others are aware of – has been demonstrated, although not always conclusively, in elephants, chimps, parrots, dolphins and ravens, for example. Dolphins are even aware of lacking knowledge. Train a dolphin to answer a question such as “was that a high or low-frequency tone you just heard?” and they give sensible answers, even giving a “don’t know” when the right response isn’t clear. Some primates spontaneously seek further information when posed a question that they can’t answer, suggesting they know both that they don’t know and that they can change that. Things look more mixed when we consider abstract knowledge: the ability we have to understand abstract properties such as weight or force, and squirrel away knowledge gained in one situation to be applied in some future, different context. Great apes instinctively know that, of two identical cups on a seesaw, the lower one is more likely to contain food. “They have a spontaneous preference, from the first time, for the lower cup,” says Christoph Voelter, who researches animal cognition at the University of St Andrews, UK. “They seem to have certain physical knowledge about the world.” New Caledonian crows, on the other hand, don’t have this know-how and make “mistakes” when assessing which stones will exert the most force on a lever to release food. “Crows aren’t using knowledge of force when initially solving the problem,” says Alex Taylor of the University of Auckland, New Zealand – rather, they seem to use trial and error.
3-20-17 Parrots find ‘laughter’ contagious and high-five in mid air
Parrots find ‘laughter’ contagious and high-five in mid air
Chortling parrots join humans, apes and rats in elite club of species that find fun infectious and enjoy a laugh or two together. If your parrot is feeling glum, it might be tweetable. Wild keas spontaneously burst into playful behaviour when exposed to the parrot equivalent of canned laughter – the first birds known to respond to laughter-like sounds. The parrots soared after one another in aerobatic loops, exchanged foot-kicking high fives in mid-air and tossed objects to each other, in what seems to be emotionally contagious behaviour. And when the recording stops, so does the party, and the birds go back to whatever they had been doing. We already knew that these half-metre-tall parrots engage in playful behaviour, especially when young. What’s new is that a special warbling call they make has been shown to trigger behaviour that seems to be an equivalent of spontaneous, contagious laughter in humans. Moreover, it’s not just the young ones that respond, adults of both sexes join in the fun too. (Webmaster's comment: Humor is universal! In college I observed that lab rats are especially humorous and laugh, tease and play all the time.)
3-16-17 Chimp filmed cleaning a corpse’s teeth in a mortuary-like ritual
Chimp filmed cleaning a corpse’s teeth in a mortuary-like ritual
The never-before-seen behaviour suggests that chimpanzees can be curious about death and may shed light on the origins of human mortuary practices. For the first time, a chimpanzee has been observed using tools to clean the corpse of a deceased group member. This behaviour could shed light on the evolutionary origins of human mortuary practices. A female chimpanzee, Noel, at Chimfunshi Wildlife Orphanage Trust in Zambia sat down by the dead body of a young male, Thomas, whom she had previously adopted. She then selected a firm stem of grass, and started to intently remove debris from his teeth. She continued doing this even after the rest of the group had left the corpse. A team of scientists from the University of St Andrews, UK, who observed the behaviour think this could mean that the long-lasting social bonds that chimpanzees form continue to influence their behaviour even after their bonding partner has died. “The report is important because it indicates once more that the human species is not the only one capable of compassion,” says Edwin van Leeuwen, lead author of the study. It appears that chimps, like humans, treat deceased members of their own species sensitively, rather than treating them like inanimate objects – especially when the deceased is a close associate. “This is certainly an interesting and noteworthy observation, another case of chimpanzees showing unusual behaviour in the presence of deceased group members,” says Klaus Zuberbuehler, also at St Andrews, who wasn’t involved in the study. “We have seen similar behaviour in our wild group of chimps in Budongo forest, Uganda, where individuals groomed an adult female, who had just been killed, for an extended period of time.”
3-5-17 ‘Monkeytalk’ invites readers into the complex social world of monkeys
‘Monkeytalk’ invites readers into the complex social world of monkeys
Researcher shares stories of science and life in the field. In a new book, a primatologist discusses what’s known about intelligence and social behavior in several monkey species, including Barbary macaques. The social lives of macaques and baboons play out in what primatologist Julia Fischer calls “a magnificent opera.” When young Barbary macaques reach about 6 months, they fight nightly with their mothers. Young ones want the “maternal embrace” as they snooze; mothers want precious alone time. Getting pushed away and bitten by dear old mom doesn’t deter young macaques. But they’re on their own when a new brother or sister comes along. In Monkeytalk, Fischer describes how the monkey species she studies have evolved their own forms of intelligence and communication. Connections exist between monkey and human minds, but Fischer regards differences among primate species as particularly compelling. She connects lab studies of monkeys and apes to her observations of wild monkeys while mixing in offbeat personal anecdotes of life in the field. Fischer catapulted into a career chasing down monkeys in 1993. While still in college, she monitored captive Barbary macaques. That led to fieldwork among wild macaques in Morocco. In macaque communities, females hold central roles because young males move to other groups to mate. Members of closely related, cooperative female clans gain an edge in competing for status with male newcomers. Still, adult males typically outrank females. Fischer describes how the monkeys strategically alternate between attacking and forging alliances. (Webmaster's comment: Where it all started.)
2-9-17 Orangutan squeaks reveal language evolution, says study
Orangutan squeaks reveal language evolution, says study
Orangutan kiss squeaks could provide a glimpse of how our ancestors combined vowels and consonants to form the first words. Scientists who spent years listening to the communication calls of one of our closest ape relatives say their eavesdropping has shed light on the origin of human language. Dr Adriano Reis e Lameira from Durham University recorded and analysed almost 5,000 orangutan "kiss squeaks". He found that the animals combined these purse-lipped, "consonant-like" calls to convey different messages. This could be a glimpse of how our ancestors formed the earliest words. The findings are published in the journal Nature Human Behaviour.
2-5-17 The secret trade in baby chimps
The secret trade in baby chimps
A secret network of wildlife traffickers selling baby chimpanzees has been exposed by a year-long BBC News investigation. The tiny animals are seized from the wild and sold as pets. The BBC’s research uncovered a notorious West African hub for wildlife trafficking, known as the “blue room”, and led to the rescue of a one-year-old chimp. In a dusty back street of Abidjan, Ivory Coast’s largest city, a tiny chimpanzee cries out for comfort. His black hair is ruffled and his dirty nappy scrapes the concrete floor as he crawls towards the familiar figures of the men who have been holding him captive. The baby chimp, ripped away from his family in the wild, is the victim of a lucrative and brutal smuggling operation, exposed by a 12-month-long BBC News investigation spanning half a dozen countries. (Webmaster's comment: And once they grow up they are extremely dangerous and will try to dominate you and tear you face off. They can never be pets past childhood.)
1-30-17 Chimps beat up, murder and then cannibalise their former tyrant
Chimps beat up, murder and then cannibalise their former tyrant
A gang of chimps overthrew their alpha male, ostracised him for years and then killed him when he returned. It was a gruesome scene. The body had severe wounds and was still bleeding despite having been lying for a few hours in the hot Senegalese savanna. The murder victim, a West African chimpanzee called Foudouko, had been beaten with rocks and sticks, stomped on and then cannibalised by his own community. This is one of just nine known cases where a group of chimpanzees has killed one of their own adult males, as opposed to killing a member of a neighbouring tribe. These intragroup killings are rare, but Michael Wilson at the University of Minnesota says they are a valuable insight into chimp behaviour such as male coalition building. “Why do these coalitions sometimes succeed, but not very often? It’s at the heart of this tension between conflict and cooperation, which is central to the lives of chimpanzees and even to our own,” he says. Chimps usually live in groups with more adult females than males, but in the group with the murder it was the other way round. “When you reverse that and have almost two males per every female — that really intensifies the competition for reproduction. That seems to be a key factor here,” says Wilson. Jill Pruetz at Iowa State University, who has been studying this group of chimpanzees in south-eastern Senegal since 2001, agrees. She suggests that human influence may have caused this skewed gender ratio that is likely to have been behind this attack. In Senegal, female chimpanzees are poached to provide infants for the pet trade.
1-10-17 Primate tool-use: Chimpanzees make drinking sticks
Primate tool-use: Chimpanzees make drinking sticks
Researchers have used camera traps to film tool-use that is unique to chimpanzees in Ivory Coast. The footage revealed that the clever primates habitually make special water-dipping sticks - chewing the end of the stick to turn it into a soft, water-absorbing brush. Primate researchers examined the "dipping sticks" and concluded they were made specifically for drinking. The findings are reported in the American Journal of Primatology. Lead researcher Juan Lapuente, from the Comoe Chimpanzee Conservation Project, in Ivory Coast, explained that using similar brush-tipped sticks to dip into bees' nests for honey was common in chimpanzee populations across Africa. "But the use of brush-tipped sticks to dip for water is completely new and had never been described before," he told BBC News. "These chimps use especially long brush tips that they make specifically for water - much longer than those used for honey." The researchers tested the chimps' drinking sticks in an "absorption experiment", which showed that the particularly long brush-tips provided an advantage. "The longer the brush, the more water they collect," said Mr Lapuente.
1-6-17 Oxytocin surge before a fight helps chimps bond with their group
Oxytocin surge before a fight helps chimps bond with their group
A spike in the “cuddle hormone” helps chimp comrades bond for war with rival groups, and something similar seems to happen in humans. Is the fabled “cuddle hormone” really a “warmone”? Oxytocin levels surge in troops of chimpanzees preparing for conflict with rival groups to defend or expand their territory. The finding is at odds with the prevailing image of oxytocin as something that helps strengthen bonds between parent and infant, or foster friendships. But given its capacity to strengthen loyalty, oxytocin could also be a warmonger hormone that helps chimps galvanise and cooperate against a common enemy. Catherine Crockford of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and her colleagues monitored two rival groups of chimpanzees in the Taï National Park in Ivory Coast, each containing five males and five females, for prolonged periods between October 2013 and May 2015. Thanks to trust built up between the team and the chimps, the team could safely track and video the groups – even during conflict, observing at close quarters what was happening. Crucially, the team was also able to pipette up fresh samples from soil when chimps urinated.
12-15-16 Chimps look at behinds the way we look at faces
Chimps look at behinds the way we look at faces
Humans are really good at picking out faces. Our brains are so good at this that we even see faces in places they don’t exist — like Jesus on toast. Flip a face upside down, though, and the brain needs an extra moment to determine that, yes, that’s a face. This is known as the inversion effect. And a new study finds that we’re not the only species to demonstrate it: Chimps do, too. Only they do it with butts. And this says something about human evolution — but we’ll get to that in a bit. In 2008, Frans de Waal and Jennifer Pokorny of Emory University in Atlanta showed in an Ig Nobel–winning experiment that chimpanzees could recognize each other from their behinds — or at least photographs of them. The chimp rear, it turns out, conveys important information about sex and, in females, ovulation status. Both males and females pay attention to those signals, which are important in mating and competition.
12-9-16 Monkeys should be able to talk just like us – so why don’t they?
Monkeys should be able to talk just like us – so why don’t they?
There’s nothing anatomical stopping monkeys from making human-like sounds we could understand finds a new study, which suggests they lack the brains for it. Ooh, ooh, ooh, ee, ee, ee! Shouting monkeys may have more sophisticated vocal abilities than we give them credit for. It seems that the anatomy of their vocal tract is theoretically capable of producing the five basic vowel sounds on which most human languages are based – and these could be used to form intelligible sentences. The results add to a growing body of evidence that some monkeys and apes can mimic or generate rudimentary sounds needed for speech-like communication. “No one can say now that there’s a vocal anatomy problem with monkey speech,” says Asif Ghazanfar at Princeton University, and co-leader of the study team. “They have a speech-ready vocal anatomy, but not a speech-ready brain. Now we need to find out why the human but not the monkey brain can produce language.”
11-8-16 Old bonobos have bad eyesight — just like us
Old bonobos have bad eyesight — just like us
Older bonobos are longsighted — they have presbyopia — just like many older humans, a new study finds. It’s a familiar sight: Your mom or grandmother picks up a document and immediately holds it out at arm’s length to make out the small letters on the page, while simultaneously reaching for her reading glasses. As people age, their ability to see things close up often fades, a condition known as presbyopia. The eye can no longer focus light on the retina, focusing it instead just behind and causing poor close-up vision. Many have thought that presbyopia was a consequence of living in an era in which people are overburdened by tasks that require frequently focusing in the near-field of vision. But perhaps not: A new study finds that if bonobos could read, they too would need glasses as they age.
11-7-16 Middle-aged bonobos need reading glasses to groom their friends
Middle-aged bonobos need reading glasses to groom their friends
The eyesight of older bonobos appears to deteriorate at almost the same rate as in humans, implying that it’s a natural process, not lifestyle-related. If only they had “grooming glasses” they’d be fine. But in the absence of a pair of specs, ageing bonobos have been found to compensate for dodgy eyesight by focusing on fur that’s further away. The discovery of five cases of age-related long-sightedness at a bonobo colony in Wamba, Democratic Republic of the Congo, has demonstrated for the first time that ageing bonobos and humans develop poor eyesight at almost exactly the same rate. This suggests that it might be an unavoidable throwback to a common ancestor of apes and humans, rather than a result of too much staring at books and computer screens. The team inferred deteriorating eyesight from the increasing distance between the eyes of a bonobo and their grooming target as they got older. “I didn’t expect age to be such a strong predictor of long-sightedness,” says lead researcher, Heung Jin Ryu of the Primate Research Institute at Kyoto University, Japan. Nor did he expect the compensatory increase.
10-19-16 Some of our Stone Age tools may just be crafty monkey throwaways
Some of our Stone Age tools may just be crafty monkey throwaways
Capuchins make stone flakes that could be mistaken for hominin tools, but they do so by accident in search of mineral dust they lick, perhaps as a medication. Toolmaking may not have been such a unique feat for our immediate ancestors after all – even modern monkeys have now been found to create stone tools. The surprising finding casts doubt on the assumption that intentional stone crafting required complex skills found only in hominins, such as changes in hand shape, coordination and cognitive skills. It also raises the possibility that at least some of the ancient tools we attribute to human ancestors were actually the handiwork of monkeys.
10-19-16 Wild monkeys throw curve at stone-tool making's origins
Wild monkeys throw curve at stone-tool making's origins
Unlike early hominids, capuchins don’t use sharp-edged rocks to dig or cut. A capuchin monkey in Brazil uses a handheld stone to hammer an embedded rock. Researchers say these wild primates unintentionally detach pieces of rock shaped like basic hominid stone tools, raising questions about how toolmaking evolved. A group of South American monkeys has rocked archaeologists’ assumptions about the origins of stone-tool making. Wild bearded capuchin monkeys in Brazil use handheld stones to whack rocks poking out of cliffs and outcrops. The animals unintentionally break off sharp-edged stones that resemble stone tools made by ancient members of the human evolutionary family, say archaeologist Tomos Proffitt of the University of Oxford and his colleagues. It’s the first observation of this hominid-like rock-fracturing ability in a nonhuman primate. The new finding indicates that early hominids needed no special mental ability, no fully opposable thumbs and not even any idea of what they were doing to get started as toolmakers, the researchers report October 19 in Nature. All it may have taken was a penchant for skillfully pounding rocks, as displayed by capuchins when cracking open nuts (SN Online: 4/30/15).
10-6-16 Chimps, bonobos and orangutans grasp how others view the world
Chimps, bonobos and orangutans grasp how others view the world
Apes’ ability to anticipate how a misinformed person will behave suggests they can see the world from the perspective of others – though maybe not consciously. Apes may be even more like us than we thought. They appear to anticipate that a person’s actions will follow his or her beliefs, even when they know the person is wrong – an ability never before demonstrated in non-human primates. The capacity to infer what others might be thinking, known as theory of mind, is central to what makes us human, and is reflected in the ways we cooperate and communicate, says Christopher Krupenye at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. Humans, for example, possess an awareness of false beliefs held by other individuals, recognising that the thoughts of others don’t necessarily reflect reality. To see whether apes have this same type of awareness, Krupenye, Fumihiro Kano at Kyoto University in Japan, and their colleagues filmed scenarios designed to stimulate apes. The videos involve conflict between pairs of human actors, one of whom is dressed in a King Kong costume. “The apes are curious; they want to know what’s going on,” says Krupenye.
10-6-16 Chimps, other apes take mind reading to humanlike level
Chimps, other apes take mind reading to humanlike level
A group of captive apes, including this orangutan, performed tests indicating that they can grasp when others are about to act based on false beliefs. This finding indicates that social thinking skills of apes and humans are more alike than previously thought. Apes understand what others believe to be true. What’s more, they realize that those beliefs can be wrong, researchers say. To make this discovery, researchers devised experiments involving a concealed, gorilla-suited person or a squirreled-away rock that had been moved from their original hiding places — something the apes knew, but a person looking for King Kong or the stone didn’t. “Apes anticipated that an individual would search for an object where he last saw it, even though the apes knew that the object was no longer there,” says evolutionary anthropologist Christopher Krupenye. If this first-of-its-kind finding holds up, it means that chimpanzees, bonobos and orangutans can understand that others’ actions sometimes reflect mistaken assumptions about reality. Apes’ grasp of others’ false beliefs roughly equals that of human 2-year-olds tested in much the same way, say Krupenye of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and his colleagues.
9-5-16 Bonobos rival chimps at the art of cracking oil palm nuts
Bonobos rival chimps at the art of cracking oil palm nuts
Bonobos in an African sanctuary use stones to crack oil palm nuts surprisingly well, researchers say. These apes hold nut-cracking stones in 15 different ways, and use 10 hand grips not previously described for tool-using chimps or monkeys. Bonobos — chimpanzees’ sister species — don’t get the credit they deserve as tool users. Bonobos ranging through a sanctuary’s protected forests in the Democratic Republic of Congo crack nuts with stones nearly as well as wild chimps in other parts of Africa do, researchers report August 26 in the American Journal of Primatology. Wild bonobos have rarely been observed using any object as a tool and have never been reported to pound open nuts with stones. All 18 adult and adolescent bonobos tracked during April and May 2015 cracked oil palm nuts with stones of various sizes that researchers had placed near oil palm trees, says a team led by Johanna Neufuss of the University of Kent, England. Bonobos chose pounding stones well-suited to busting palm oil nutshells. These animals employed 15 grips to hold nut-cracking stones, including 10 grips not previously observed in nonhuman primates. Several novel grips involved holding a stone with the thumb and one or a few fingers while bracing the tool against the palm.
9-5-16 Eastern gorillas threatened with extinction
Eastern gorillas threatened with extinction
The eastern gorilla is now on the endangered species list. A surge in illegal hunting is threatening the eastern gorilla, the world's largest primate, an international conservation group has said. The International Union for Conservation of Nature (IUCN) Red List says just 5,000 of the animals remain in their central African habitat. The number of eastern gorillas has declined more than 70% in two decades. Four of the six great apes are now critically endangered, the IUCN says. This means they are just one step away from extinction.
8-11-16 Cherry or rhubarb? Orangutan mixes tasty cocktails in its mind
Cherry or rhubarb? Orangutan mixes tasty cocktails in its mind
A pleasure-seeking ape can predict the taste of cocktails it has never tried before, which was thought to be something only humans can do. What’s an orangutan’s favourite cocktail? By providing a captive orangutan with its own personal cocktail bar, a group of researchers found that out, and in the process discovered that these great apes have a predictive ability thought to be unique to humans. Naong, a male orangutan based at a Swedish zoo, was offered three distinct-tasting fruit juices – cherry, rhubarb and lemon – as well as cider apple vinegar. Each was in a small bottle on a table adjacent to his cage, and which he could access using a straw. He learned their flavours, and also the flavour of every possible pairing of the liquids mixed for him by a personal bartender. The researchers found that Naong not only remembered the flavour of each combination, but could predict whether combinations he had never tasted before would taste pleasant.
7-27-16 Orangutan learns to mimic human conversation for the first time
Orangutan learns to mimic human conversation for the first time
‘Rocky’ the ginger ape has astonished experts by producing sounds similar to words, a feat that might help us study the evolutionary origins of human speech. An orangutan has shown an ability to emulate human speech for the first time — a feat that gets us closer to understanding how human speech first evolved from the communications of ancestral great apes. ‘Rocky’ the ginger ape has astonished experts by producing sounds similar to words in a “conversational context”. “This opens up the potential for us to learn more about the vocal capacities of early hominids that lived before the split between the orangutan and human lineages to see how the vocal system evolved towards full-blown speech in humans,” says lead researcher Adriano Lameria, from the University of Durham, UK.
7-27-16 Orangutan 'copies human speech'
Orangutan 'copies human speech'
An orangutan copying sounds made by researchers offers new clues to how human speech evolved, scientists say. Rocky mimicked more than 500 vowel-like noises, suggesting an ability to control his voice and make new sounds. It had been thought these great apes were unable to do this and, since human speech is a learned behaviour, it could not have originated from them. Study lead Dr Adriano Lameira said this "notion" could now be thrown "into the trash can". Dr Lameira, who conducted the research at Amsterdam University prior to joining Durham University, said Rocky's responses had been "extremely accurate".
7-22-16 Monkeys who use tools
Monkeys who use tools
Wild capuchin monkeys in Brazil have used stone tools to prepare their food for at least 700 years, new research reveals. Archaeologists discovered dozens of stone hammers and anvils in Brazil’s Serra da Capivara National Park—the oldest known tools not belonging to either humans or chimpanzees. Operating carefully so as not to strike their own fingers, the monkeys use smaller stones as hammers to crack open cashew nuts on a heavier, flat stone; when they’re done eating the protein-rich nutmeats, they store their tools in nearby caches for future use, like a set of utensils at a restaurant. Scientists observed older monkeys teaching their youngsters how to use the stones.
7-19-16 Well-travelled chimps more likely to pick up tools and innovate
Well-travelled chimps more likely to pick up tools and innovate
What makes some apes pick up tools and others not has perplexed scientists, but hunger brought on by travel appears to be a big motivator. Spot a tool-using chimpanzee in Uganda’s Budongo Forest, and you could probably say it’s come a long way – in more ways than one. Chimps here are more likely to make use of tools to gather food if they have used up precious energy reserves travelling in the previous week. The finding suggests that balancing energy needs might push apes into experimenting with tools, with possible implications for understanding what drove our ancestors to develop technology. One explanation of tool use in animals is that it starts by chance and then spreads through a population by social learning. An alternative view is that ecological factors nudge animals into trying tools, with two main theories of how it happens. One is that animals may be forced to try out tool use to exploit new food sources when they are low on energy – if their preferred foods are in short supply, for instance. The other is that animals may be tempted into innovating after encountering new foods that they can only access with tools.
7-13-16 Gorillas may have evolved a way to beat a cheating berry plant
Gorillas may have evolved a way to beat a cheating berry plant
A "deceitful" West African plant makes super-sweet, but low-calorie berries to attract animals that disperse their seeds. Gorillas can see through the ploy – at least, that’s the theory. Fool me once, perhaps… it looks like gorillas don’t get fooled twice, at least not by a cheating plant. If true, that makes them smarter than humans and almost 50 other primate species all of whom can be tricked by a West African plant that grows super-sweet but low-calorie berries. Pentadiplandra brazzeana’s fruit is packed with a protein called brazzein, which mimics the taste of high-energy sugary fruits, but costs the plant less to make. So sweet is brazzein that it’s even been suggested as a new artificial sweetener for human consumption. The problem for hungry primates is that it’s mostly a waste of time eating the plant’s fruit. Brenda Bradley, an anthropologist at George Washington University, thinks the plant is probably producing cheap, sweet proteins to “trick” African primates into eating the low-calorie berries and dispersing their seeds.
7-11-16 Capuchin monkeys may have taught us how to eat cashew nuts
Capuchin monkeys may have taught us how to eat cashew nuts
Stones found in Brazil seem to be nutcrackers used by monkeys hundreds of years ago, hinting that human settlers could have copied them to enjoy the nuts. They are literally a tough nut to crack. To enjoy tasty cashews you first have to figure out a way to remove the shells, which contain a caustic chemical. The bearded capuchin monkeys of Brazil may have been up to the task for centuries – and watching them work could even have taught us how to eat cashew nuts safely. We know that at least three non-human primates use stone tools: chimpanzees in West Africa, long-tailed macaques in Thailand and bearded capuchins in Brazil. The first ever “primate archaeology” dig – carried out in Ivory Coast and published in 2007 – confirmed that chimpanzees have been living through their Stone Age for at least 4300 years. A similar investigation in Thailand published earlier this year traced back the macaque Stone Age at least 65 years.
7-11-16 Earliest evidence of monkeys’ use of stone tools found
Earliest evidence of monkeys’ use of stone tools found
Capuchins in Brazil used flat ‘anvils’ and round ‘hammers’ to smash nuts at least 600 years ago. Using tools is very old monkey business. Capuchins in northeast Brazil have wielded stones to crack open cashew nuts for 600 to 700 years, researchers report July 11 in Current Biology. Unearthed “hammers” and “anvils” are the earliest evidence of monkey tool use to date. Today, Brazilian bearded capuchin monkeys (Sapajus libidinosus) still open cashews by placing them on the flat surfaces of anvil rocks and pounding the nuts with large stones. Unlike pebbles and other rocks, the tool stones are distinctively heavy, blemished with wear marks, greased with cashew residue and clustered under cashew trees, Michael Haslam of the University of Oxford and colleagues found.
7-11-16 Monkey archaeology: Ancient evidence of tool use found
Monkey archaeology: Ancient evidence of tool use found
Primate archaeology is a new and unusual-sounding field, but it has revealed ancient evidence of some clever and dextrous monkey culture. Researchers from Oxford University, working in Brazil, found ancient "nut-cracking tools" - 700-year-old stone hammers that capuchin monkeys used to open cashew nuts. This is the earliest evidence yet of monkey tool use outside Africa.
7-10-16 Documentary looks for meaning in Koko the gorilla’s life
Documentary looks for meaning in Koko the gorilla’s life
Film focuses on ape’s relationship with researcher. For the last four decades, Koko, the world’s most famous gorilla, has lived in a trailer in Silicon Valley, the subject of the longest-running project on ape sign language. With a reported vocabulary of hundreds of signs, Koko has appeared to express feelings almost anyone can relate to — a love of kittens, a desire to be a mother. A new PBS documentary argues that Koko’s remarkable life “challenges what it is that makes humans unique.” The problem, though, is that the film never really makes clear what “it” is. Rather than diving into the question of ape language and dissecting Koko’s abilities, Koko — The Gorilla Who Talks focuses more on the relationship between Koko and researcher Penny Patterson. (Webmaster's comment: The first article on Koko in a 1978 issue of National Geographic began my long journey learning about animal intelligence. I still have that issue with "Conversations with a Gorilla". It had a significant influence on my life. Back issues are still available at National Geographic's website.)
6-10-16 ‘Monkey archaeology’ reveals macaque’s own Stone Age culture
‘Monkey archaeology’ reveals macaque’s own Stone Age culture
One of the first digs searching for stone tools used by monkeys has unearthed evidence that promises to change the way we study the evolution of tool use. The world’s first archaeology dig of an old world monkey culture has uncovered the tools used by previous generations of wild macaques – a group of primates separated from humans by some 25 million years of evolution. The discovery means humans aren’t unique in leaving a record of our past culture that can be pried open through archaeology. Only a few decades ago scientists thought that humans were the only species to have worked out how to turn objects in their environment into useful tools. We now know all sorts of animals can do the same – but the tools of choice are usually perishable materials like leafs and twigs. This makes the origin of these behaviours difficult to study, especially when you consider that the record of hominin stone tool use stretches back more than 3 million years. Burmese long-tailed macaques are a rare exception. They are renowned for their use of stone tools to crack open shellfish, crabs and nuts, making them one of the very few primates that have followed hominins into the Stone Age. (Webmaster's comment: The similar first primitive stone tools made by our hominin ancestors were made 3.3 million years ago.)
5-31-16 Are Gorillas A Danger To People?
Are Gorillas A Danger To People?
In the wake of the tragic killing of Harambe the gorilla, we explore the evidence for whether these great apes pose a danger to people. However, from the 1970s onwards the primatologist Dian Fossey transformed gorillas' reputation with her pioneering studies of wild mountain gorillas. These are a different species to Harambe, but the differences are subtle. Fossey found that the gorillas were hardly ever violent. For the most part they were peaceful. David Attenborough was filmed with some of Fossey's gorillas for the 1979 television series Life on Earth. The encounter has gone down in television history, because some of the young gorillas started playing with Attenborough. (Webmaster's comment: It's PEOPLE that are dangerous to Gorillas! 100's are killed for meat and body parts every year in Africa! No child has ever died that fell into a Gorilla enclosure. The Gorillas even protect them.)
5-23-16 Monkey seen caring for dying mate then grieving after she dies
Monkey seen caring for dying mate then grieving after she dies
It’s a tear-jerker worthy of Hollywood – and one of the first examples of compassionate care and grief in a wild monkey. The alpha male of a group of snub-nosed monkeys and his dying partner spent a final, tender hour together beneath the tree from which she had fallen minutes earlier, cracking her head on a rock. Before she succumbed, he gently touched and groomed her. And after she was dead he remained by her side for 5 minutes, touching her and pulling gently at her hand, as if to try and revive her (for a full account of what happened, see “A monkey tends to his dying mate – as it unfolded”). “The case we’ve reported is particularly important because of the exclusively gentle nature of the interactions, and the special treatment of the dying female shown by the adult male,” says James Anderson of Kyoto University, Japan. “The events suggest that in the case of strongly bonded individuals at least, monkeys may show compassionate behaviour to ailing or dying individuals.” The study follows a recent report of a quasi-funeral for an adult captive chimpanzee at a sanctuary in north-west Zambia, and evidence of death-related behaviour in crows. Together, the reports add to evidence that humans may not be the only species to display grieving behaviour following bereavement, or to show respect for dead individuals with whom they have forged ties. They also hint that animals have some recognition of the finality of death. (Webmaster's comment: All of us animals share a common ancestry so we all share many of the same emotions and values and much of the same understanding of how nature works.)
5-18-16 Chimps filmed grieving for dead friend
Chimps filmed grieving for dead friend
An extraordinary film reveals never-before-seen behaviour. A unique, remarkable and intimate film may change the way we think about animals, and their ability to feel grief. The newly-published film captures the solemn reactions of a group of chimpanzees who discover the dead body of a friend. For 20 minutes, the chimpanzees quietly gather around their friend, despite offers of food to tempt them away. They gently touch and sniff his body, with chimps who were closer friends with the deceased appearing to be the most upset. An older female chimp then attends to the dead ape, tenderly attempting to clean his teeth with a stem of grass.
3-31-16 How do you bring up a baby gorilla?
How do you bring up a baby gorilla?
A baby gorilla who was born by caesarean section, is being cared for by humans until she can be reunited with her mother at Bristol Zoo. Lynsey Bugg, who is the Curator of Mammals at the zoo, said the gorilla - who has been named Afia - was getting "stronger by the day". She also described what it was like bringing up a baby gorilla at home with her family.
3-4-16 What do chimp ‘temples’ tell us about the evolution of religion?
What do chimp ‘temples’ tell us about the evolution of religion?
Biologists working in the Republic of Guinea have found evidence for an apparent "sacred tree" used by chimps, perhaps for some sort of ritual. All hail the sacred tree. I’ve often wondered aloud in the newsroom about the possibility of finding evidence of a chimp shrine, the discovery of a place where chimps pray to their deity. Biologists working in the Republic of Guinea found evidence for what seemed to be a “sacred tree” used by chimps, perhaps for some sort of ritual. Laura Kehoe of the Humboldt University of Berlin, Germany, set up camera traps by trees marked with unusual scratches. What she found gave her goosebumps: chimps were placing stones in the hollow of trees, and bashing trees with rocks. The behaviour could be a means of communication, since rocks make a loud bang when they hit hollow trees. Or it could be more symbolic. “Maybe we found the first evidence of chimpanzees creating a kind of shrine that could indicate sacred trees.”
2-26-16 Bromance helps stressed out warring chimps keep their cool
Bromance helps stressed out warring chimps keep their cool
Strong friendships in primates may have evolved to counteract the damaging health effects of living in complex social groups. When it comes to warfare, chimps are a bit like the ancient Greeks. They like to head into battle with a close friend at their side – a tactic that seems to lower their stress. Many primate species, including macaques and baboons, form strong, long-lasting social bonds with particular individuals that resemble human friendship. These relationships appear to benefit both males and females: they are associated with higher reproductive success and even longer life. In male chimps these bonds can seem surprising, given that adult males are extremely aggressive, sometimes killing each other. “Chimpanzees are highly territorial and encounters with neighbouring groups tend to be very hostile and can be deadly,” said Catherine Crockford of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, last week at the Ethological Society annual meeting in Göttingen. Yet pairs of strongly bonded males also engage in relaxed, cooperative behaviours, including sharing food and grooming vulnerable, intimate areas, such as genitalia.
2-24-16 Wild gorillas compose happy songs that they hum during meals
Wild gorillas compose happy songs that they hum during meals
Humming their individual songs may be a way for gorillas to communicate dinner times and contentment with their meals. Gorillas sing and hum when eating, a discovery that could help shed light on how language evolved in early humans. Singing seems to be a way for gorillas to express contentment with their meal, as well as for the head of the family to communicate to others that it is dinner time. Food-related calls have been documented in many animals, including chimpanzees and bonobos, but aside from anecdotal reports from zoos, there was no evidence of it in gorillas. To see if they make these noises in the wild, Eva Luef, a primatologist at the Max Planck Institute for Ornithology in Seewiesen, Germany, observed two groups of wild western lowland gorillas in the Republic of the Congo. Luef identified two different types of sound that the gorillas sometimes made when eating. One of them was humming – a steady low-frequency tone that sounds a bit like a sigh of contentment.
2-8-16 How do you prepare orangutans to go back into the wild?
How do you prepare orangutans to go back into the wild?
The school that teaches orangutans. Orangutans living at a sanctuary in Indonesia are being prepared for release back into the wild. Forest fires and poaching have led to a decrease in the population. International Animal Rescue has more than 100 at its sanctuary in Ketapang in western Kaliman province. Rehabilitation can take up to eight years.
2-4-16 First orangutan murder seen as pair team up to kill female
First orangutan murder seen as pair team up to kill female
Orangutans are normally solitary, only coming together to mate. But violence could increase as they are forced closer together by habitat destruction. It was a deadly rumble in the jungle. A female orangutan was attacked and killed by another female and a male – the first time lethal aggression has been seen in the species. Female orangutans are normally solitary, and very rarely engage in fights. It’s also unusual for females and males to form coalitions. In this case, Kondor, a young female, and Ekko, her suitor, beat and bit an older female named Sidony in the swamp forests of Indonesia’s Mawas Reserve. Sidony sustained serious wounds that became infected, and she died two weeks later.
1-18-16 How to make friends with wild gorillas
How to make friends with wild gorillas
Grauer’s gorillas are the largest primates in the world and are capable of awesome displays of power and brute strength. But a harmonious family life lies at the heart of society for these elusive and threatened giants. Wildlife cameraman and presenter Gordon Buchanan tells BBC Earth how he attempted to get to know a population of the great apes living deep in a forest in the Democratic Republic of Congo.
11-3-15 Debate over chimpanzee 'accent' study
Debate over chimpanzee 'accent' study
A debate is unfolding among primatologists about a study, published in February, which reported that chimpanzees can adapt their grunts to communicate with new neighbours. It was based on a group of chimps that moved from a Dutch safari park to Edinburgh Zoo. Now, three researchers have written to the journal Current Biology suggesting the results don't stack up. The original team has responded, and stands by its findings and conclusions.
10-9-15 Squirrel monkeys teach themselves to eat and drink from a cup
Squirrel monkeys teach themselves to eat and drink from a cup
Tool use seemed so rare in squirrel monkeys that they were considered incapable of such feats, now they've been seen carrying food and water in containers. It’s not exactly the height of good etiquette, but squirrel monkeys at a research facility in California have learned how to eat and drink from plastic cup-like objects. It’s the first time squirrel monkeys have been observed carrying food and water around in containers, and a large number of the animals learned how to do it – 39 out of 57. Previously, reports of tool use in squirrel monkeys have been so rare that they were considered incapable of such a feat. The only other non-human primates that seem able to spontaneously begin using containers are captive chimpanzees, orangutans and capuchin monkeys. In the wild, capuchins and chimpanzees have been seen using leaves to access water from tree cavities.
10-1-15 The birds that fear death
The birds that fear death
Crows will gather around their dead. And the reasons why are intriguing. Crows are now the latest in the small group of animals that are known to recognise, or perhaps even mourn their dead. Elephants, giraffes, chimpanzees and several other corvid species are also known to loiter near recently deceased mates.
9-18-15 The inner lives of animals
The inner lives of animals
The evidence shows that elephants and apes mourn their dead, becoming listless and depressed. Dolphins can recognize their own reflections, have intricate social structures, and appear to call each other by individual names. Apes and chimps make tools, plan for the future, and display empathy and inferential reasoning. Primatologist Frans de Waal, writing in The New York Times about the recent discovery of a hominin ancestor with both human and ape characteristics, blames human vanity for the belief we are separate and distinct from the "extended family" of creatures on the great continuum of evolution. "The wall between human and animal cognition," de Waal says, "is like a Swiss cheese." If you doubt our kinship with the animal kingdom, I refer you to the daily news coverage of our species' Darwinian struggles for dominance and survival. Evolution is a work in progress: We are still closer to the beasts than to the gods.
9-18-15 Apes remember major events in movies, even on a single viewing
Apes remember major events in movies, even on a single viewing
The first evidence that chimpanzees and bonobos can recall recent events comes from experiments that tested their memory of short movie clips. We all have our favourite movie moments, ones we love to watch again from time to time. Now it seems chimpanzees and bonobos, too, have the nous to recall thrilling scenes in movies they have previously seen and anticipate when they are about to come up. The results suggest apes can readily recall and anticipate significant recent events, just by watching those events once. (Webmaster's comment: Dah! If members of an animal species didn't remember major events in their lives after one occurrance they would not have survived. They would all be extinct pretty quickly.)
8-4-15 Bonobo squeaks hint at earlier speech evolution
Bonobo squeaks hint at earlier speech evolution
Wild bonobos use a single high-pitched call in a variety of contexts, showing a flexibility in their communication that was thought to be uniquely human. Bonobos are just as closely related to humans as chimpanzees, but their wild communication is much less studied. Researchers say the new findings push back the development of context-free vocal calls to our shared ancestor with bonobos, 6-10 million years ago.
7-7-15 Bonobos use a range of tools like stone-age humans
Bonobos use a range of tools like stone-age humans
The chimps' randy relatives have been seen using tools as shovels and levers in captivity, and even fashioning a spear to jab at a researcher. Bonobos can be just as handy as chimpanzees. In fact, bonobos' tool-using abilities look a lot like those of early humans, suggesting that observing them could teach anthropologists about how our own ancestors evolved such skills.
6-10-15 Cheers! Chimps' favourite tipple is sweet palm wine
Cheers! Chimps' favourite tipple is sweet palm wine
Chimps in Guinea seem to get tipsy on the booze they find at the bottom of raffia palms, in the first study of the drinking habits of wild chimpanzees. In the first study of its kind, chimps in West Africa were spotted sampling sweet palm wine on a rare but habitual basis.
6-10-15 Chimpanzees found to drink alcoholic plant sap in wild
Chimpanzees found to drink alcoholic plant sap in wild
They have shown an understanding of language and a sense of fairness, and now humans' closest primate cousins have even been found to share a taste for alcohol. Scientists studying chimpanzees in Guinea have seen evidence of long-term and recurrent ingestion of ethanol by apes. The 17-year study recorded chimps using leaves to drink fermented palm sap. Some drank enough alcohol to produce "visible signs of inebriation".
6-2-15 Listening to the language of apes
Listening to the language of apes
The similarities between apes and people have long fascinated scientists. Yet, writes Mary Colwell, the differences can be just as thrilling. "The sounds uttered by these apes have all the characteristics of true speech," wrote Garner. "The speaker is conscious of the meaning of the sound used, and uses it with the definite purpose of conveying an idea to the one addressed; the sound is always addressed to some definite one, and the speaker usually looks at the one addressed; he regulates the pitch and volume of the voice to suit the condition under which it is used; he knows the value of sound as a medium of thought. These and many other facts show that they are truly speech."
5-18-15 In U.S., more say animals should have same rights as people
In U.S., more say animals should have same rights as people
Almost a third of Americans, 32%, believe animals should be given the same rights as people, while 62% say they deserve some protection but can still be used for the benefit of humans. The strong animal rights view is up from 2008 when 25% thought animals' rights should be on par with humans'. (Webmaster's comment: We need to keep in mind that an animal has little concept of human rights. A lion that eats you is just being a lion, and a chimpanzee that tears your face off to dominate you is just being a chimpanzee.)
5-6-15 Capuchin monkeys rival chimps as highly skilled nut-crackers
Capuchin monkeys rival chimps as highly skilled nut-crackers
Monkeys observed in Brazil can use tools, but they also know it doesn't take a sledgehammer to crack a nut – instead they exercise judgement and restraint. CAPUCHIN monkeys from Brazil are famous for using hammers and anvils to crack open tasty nuts. Now it seems they do so with even more skill and judgement then we gave them credit for, rivalling skills of their brainy chimp relatives. (Webmaster's comment: They are THINKING about the best way to get the food. Exactly what you would expect of any intelligent animal, which is almost all, if not all, of them.)
4-30-15 Capuchin monkeys rival chimps as highly skilled nut-crackers
Capuchin monkeys rival chimps as highly skilled nut-crackers
Monkeys are more skillful in using tools to crack open their favourite nuts than we thought. In addition to breaking nuts open with stones and copying more experienced individuals, they exercise a great deal of judgement to optimise each nut-cracking operation. Bearded capuchin monkeys from Brazil use tools made of quartz, limestone, sandstone and wood as anvils and hammers to crack open various nuts, and young monkeys observe how the older, more proficient and dominant individuals do it before they pick up the skill.
4-17-15 Wild chimps look both ways before crossing roads
Wild chimps look both ways before crossing roads
A busy highway in Uganda is a potential death trap, but chimps have learned to look before running across, and they even wait for those less able to cross. It turns out that like us wild chimpanzees learn to respect roads, adopting the same cautious drills as humans, including looking both ways to check for traffic.
3-19-15 Orangutans cup their mouths to alter their voices
Orangutans cup their mouths to alter their voices
Orangutans use their hands to alter their voices and make themselves sound bigger, say scientists. Researchers have now studied the acoustics of these "hand-modified kiss squeaks" and shown that the animals sound bigger and "more impressive" when they use their hands in the call.
2-5-15 Chimps 'learn local grunts' to talk to new neighbours
Chimps 'learn local grunts' to talk to new neighbours
Chimpanzees can change their grunts to communicate better with new companions, according to a study of two groups that were housed together in Edinburgh.
10-22-14 Chimps filmed raiding farms to find food
Chimps filmed raiding farms to find food
Camera traps have caught wild chimpanzees in the act as they carried out night-time raids on farmland. The footage, captured by researchers from the Museum of Natural History in Paris and the Uganda Wildlife Authority, shows the chimps adapting to human pressure on their habitat.
10-8-14 The battle to make Tommy the chimp a person
The battle to make Tommy the chimp a person
Tommy is 26. He lives alone behind a trailer sales park in upstate New York. His hobbies include watching cartoons. A lawsuit submitted by a group called the Nonhuman Rights Project (NhRP) seeks to have Tommy recognised as a person under law. (Webmaster's comment: Adult male chimps are very dangerous and will severly harm or kill you if they live with you. They are just being male chimps. They have no concept of your rights whatsover. Charging them with a crime would be like charging a 2 year old. Giving them human rights makes no sense.)
10-1-14 Chimps with tools: Wild ape culture caught on camera
Chimps with tools: Wild ape culture caught on camera
Researchers have captured the spread of a new type of tool use in a wild population of chimps. As the team filmed the animals at a field station in Uganda, they noticed that some of them started to make a new type of leaf sponge - something the animals use to drink. This new behaviour soon spread throughout the group. (Webmaster's comment: But they have yet been observed to chip-shape a rock like early primate humans first did 2.7 million years ago. A million years from now what evolves from chimps may also evolve the mental ability to do that.)
9-30-14 Chimp social network shows how new ideas catch on
Chimp social network shows how new ideas catch on
Three years ago, an adult chimpanzee called Nick dipped a piece of moss into a watering hole in Uganda's Budongo Forest. Watched by a female, Nambi, he lifted the moss to his mouth and squeezed the water out. Nambi copied him and, over the next six days, moss sponging began to spread through the community. A chimp trend was born.
9-18-14 Murder 'comes naturally' to chimpanzees
Murder 'comes naturally' to chimpanzees
A major study suggests that killing among chimpanzees results from normal competition, not human interference. Apart from humans, chimpanzees are the only primates known to gang up on their neighbours with lethal results. Murder rates in different chimp communities simply reflect the numerical make-up of the local population.
9-10-14 Fish that picks its work partners wisely
Fish that picks its work partners wisely
TO COOPERATE or not, that is the question, and trout know the answer. Coral trout have joined the exclusive club of species, including humans and chimps, that can decide whether to work with animals of another species on a task.
7-11-14 How much science is there in new Planet of the Apes film?
How much science is there in new Planet of the Apes film?
The latest installment in the Planet of the Apes film franchise opens in the US on Friday. The rubber masks of the 60s and 70s films have been discarded in favour of motion capture suits and CGI. But how much did science inform the new movie's portrayal of our close relatives? (Webmaster's comment: Frans De Waal compares the film's ape behavior with real life ape behavior. The film gets much of it wrong but the comparison is educational.)
7-10-14 Chimpanzee brain power is strongly heritable
Chimpanzee brain power is strongly heritable
If a chimpanzee appears unusually intelligent, it probably had bright parents. That's the message from the first study to check if chimp brain power is heritable
7-3-14 Chimpanzee language: Communication gestures translated
Chimpanzee language: Communication gestures translated
Researchers say they have translated the meaning of gestures that wild chimpanzees use to communicate.
5-7-14 Only known chimp war reveals how societies splinter
Only known chimp war reveals how societies splinter
A weak leader is struggling to hold onto power as ambitious upstarts plot to take over. As tensions rise, the community splits and the killing begins. The war will last for years. No, this isn’t the storyline of an HBO fantasy drama, but real events involving chimps in Tanzania’s Gombe Stream National Park. A look at the social fragmentation that led to a four-year war in the 1970s now reveals similarities between the ways chimpanzee and human societies break down.
10-14-13 Apes comfort each other 'like humans'
Apes comfort each other 'like humans'
Young bonobos that are more "socially competent" are more likely to cuddle and calm other apes that are in distress, research has revealed.
12-7-07 Animals Do the Cleverest Things
Animals Do the Cleverest Things
The chimp who outwits humans; the dolphin who says it with seaweed; the existential dog -- the more we learn about other animals the harder it is to say we're the smartest species.
10-31-06 Elephants' jumbo mirror ability
Elephants' jumbo mirror ability
Elephants can recognize their own reflection, showing self-awareness seen before only in humans, great apes and bottlenose dolphins, scientists say.