Wild chimpanzees share food with friends


This 10 October 2018 video from the Ivory Coast says about itself:

Honey sharing in wild chimpanzees of the Taï Forest – Taï Chimpanzee Project

From the Max Planck Institute for Evolutionary Anthropology in Germany:

Wild chimpanzees share food with their friends

October 10, 2018

Summary: Why share food with non-family members when there is no immediate gain? An international team of researchers conducted observations of natural food sharing behavior of the chimpanzees of the Tai National Park, Ivory Coast. They found that chimpanzees who possess large, desirable food items, like meat, honey or large fruit share food with their friends, and that neither high dominance status nor harassment by beggars influenced possessors’ decisions to share.

Sharing meat after hunting and exchanging other valued food items is considered key in the evolution of cooperation in human societies. One prominent idea is that humans share valuable foods to gain future favors, such that those we chose to share with are more likely to cooperate with us in the future. Despite regularly occurring in humans, sharing food outside of kinship or mating relationships is rare in non-human animals. Our two closest living relatives, chimpanzees and bonobos, are two of the rare exceptions, and because of the important role of food sharing in human evolution, examining the sharing patterns of chimpanzees can help to answer questions on how sharing food amongst adults evolved and how it may have shaped human cooperation.

Researchers from the MPI-EVA observed natural food sharing behavior of the chimpanzees of the Tai National Park, Ivory Coast, and found that chimpanzees are very selective in who they share desirable food items, like meat, honey or large fruits, with. They show that chimpanzees were more likely to share food with their friends, and that neither high dominance status nor harassment by beggars influenced their decision. This complements results from another study by the same team published last month that examined meat sharing after group hunting of monkeys. There they found that chimpanzees in possession of meat after successful hunts were likely to reward other hunters by sharing with them. “Collectively our research shows that the chimpanzees decide when to share food based on the likelihood that this favor will be returned in the future,” says Liran Samuni, first author of both studies. “Or, in case of sharing after group hunts, sharing of meat is returning the favor for helping out.”

Previous studies in another subspecies of chimpanzees have suggested that food sharing in chimpanzees mainly occurs because of harassment pressure from beggars. “This was not the case for the Tai chimpanzees”, Catherine Crockford, senior author on the studies, points out, “emphasizing the high variation in cooperation across chimpanzee populations.” Human populations also vary in how cooperative they are and research is ongoing in both humans and non-human animals assessing what might make some populations more cooperative than others. “The need to stay in a cohesive unit, because of high predation pressure, or the capability to exhibit strong cohesion, because of rich food sources, are two possible scenarios to promote the expression of cooperative acts”, suggests Roman Wittig, the second senior author of the studies.

Additionally, the researchers collected urine samples from chimpanzees after hunting and food sharing events and measured the hormone oxytocin. “We know that oxytocin plays a strong role in lactation, which you could look at as an example of food sharing between mother and infant, and is generally involved in social behavior and bonding”, Liran Samuni explains. The researchers found high levels of oxytocin after chimpanzees shared meat and other valued foods, and after chimpanzee participated in hunting with others. “That we found higher oxytocin levels after both hunting and sharing adds to the idea that oxytocin is a key hormone involved in cooperation in general”, Liran Samuni points out.

The researchers conclude that like humans, Tai chimpanzee sharing is selective, and that friends and others that helped acquiring the food benefit more. Emotional connection, as is obvious amongst friends, likely played a crucial role in the evolution of human cooperation.

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Apes have ‘human’ muscles too


Figure showing the striking similarities between the head muscles of common chimpanzees, bonobos and humans: the very rare exceptions are those shown in colors and with text. Credit: © Rui Diogo

From ScienceDaily:

‘Uniquely human’ muscles have been discovered in apes

Apes also have muscles long-believed to be only present in humans and used for walking on two legs, using complex tools, and sophisticated facial and vocal communication

May 23, 2018

Muscles once thought ‘uniquely human’ have been discovered in several ape species, challenging long-held theories on the origin and evolution of human soft tissues. The findings question the anthropocentric view that certain muscles evolved for the sole purpose of providing special adaptations for human traits, such as walking on two legs, tool use, vocal communication and facial expressions. Published in Frontiers in Ecology and Evolution, the study highlights that thorough knowledge of ape anatomy is necessary for a better understanding of human evolution.

“This study contradicts key dogmas about human evolution and our distinct place on the ‘ladder of nature’,” says Rui Diogo, an Associate Professor in the Department of Anatomy at Howard University, Washington, USA. “Our detailed analysis shows that in fact, every muscle that has long-been accepted as ‘uniquely human’ and providing ‘crucial singular functional adaptations’ for our bipedalism, tool use and vocal and facial communications is actually present in the same or similar form in bonobos and other apes, such as common chimpanzees and gorillas.”

Long-standing evolutionary theories are largely based on the bone structures of prehistoric specimens — and, according to Diogo, also on the idea that humans are necessarily more special and complex than other animals. These theories suggest that certain muscles evolved in humans only, giving us our unique physical characteristics. However, verification of these theories has remained difficult due to scant descriptions of soft tissues in apes, which historically have mainly focused on only a few muscles in the head or limbs of a single specimen.

Diogo explains, “There is an understandable difficulty in finding primate, and particularly ape, specimens to dissect as they are so rare both in the wild and museums.”

To find enough data to complete this research, Diogo compiled all previous information on ape anatomy based on studies with colleague Bernard Wood. He also conducted anatomical research on several bonobos that died of natural causes, together with colleagues at the University of Antwerp under the Bonobo Morphology Initiative 2016 — looking for the presence of seven different muscles thought to have evolved only in our species.

Diogo discovered that these seven muscles were present in apes in a similar or even exact form. For example the fibularis tertius muscle, said to be uniquely associated with human bipedalism (walking on two legs), was present in half the examined bonobos. Similarly, both the laryngeal muscle arytenoideus obliquus and the facial muscle risorius — thought to have evolved for our uniquely sophisticated vocal and facial communication, respectively — were present in at least some chimpanzees and/or gorillas.

These findings open crucial new directions for research and question our understanding of human evolution. “The picture emerging from this research is that the origin and evolution of human soft-tissue is clearly more complex — and not as exceptional — as first thought”, says Diogo.

“We need a more thorough examination of why these muscles are present in apes and, in some cases, in just part of a population within a certain species”, he says. “Are these muscles essential for the apes that have them, as adaptationist evolutionary scientists would argue? Or are they evolutionary neutral features related to how their bodies develop, or simply by-products of other features?”

He concludes, “Most theories of human evolution give the impression that humans are markedly distinct from apes anatomically, but these are unverifiable ‘just-so stories’. The real evidence shows we are not so different overall. This study highlights that a thorough knowledge of ape anatomy is necessary for a better understanding of our own bodies and evolutionary history.”

Pregnant bonobos get a little delivery help from their friends. Observations of captive apes suggest they, like humans, have ‘social’ births. By Bruce Bower, 1:26pm, May 24, 2018.

While humans and other species share some of the same genetic information, new research found that humans are unique among mammals when it comes to the types and diversity of microorganisms on our skin. This difference could have implications for our health and immune systems: here.

Chimpanzee brains similar to human ancestors’


This video says about itself:

How different are human and chimpanzee brain stem cells?

27 January 2017

We share between 94 and 99% of our DNA with our chimpanzee cousins, but how do our brains compare? Watch this video by Felipe Mora-Bermúdez to find out what he has learned from studying brain stem cells from humans and chimps.

You can read his full publication on this work in the journal eLife here.

Felipe is a postdoc in the lab of Wieland Huttner at the Max Planck Institute of Molecular Cell Biology and Genetics in Dresden, Germany.

By Bruce Bower, 3:00pm, March 26, 2018:

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.

“I was really wrong about the handful of Australopithecus endocasts”, Falk says. The endocasts were made from A. africanus and A. sediba fossils dating to between roughly 2 million to 3 million years ago (SN: 8/10/13, p. 26).

And in one chimp, the new study finds, a pair of grooves correspond with those on a Homo naledi endocast that were described in 2017 as humanlike (SN Online: 4/25/17). H. naledi, a small-brained species with many humanlike skeletal features, inhabited southern Africa close to 300,000 years ago (SN: 6/10/17, p. 6).

Still, researchers have spent decades debating the implications of partially preserved brain surface features on hominid endocasts. And the new findings based on MRIs are also controversial.

Nothing in the new chimp study undermines the original finding of humanlike folds in H. naledi’s frontal brain, says biological anthropologist Shawn Hurst of Indiana University Bloomington. The frontal brain grooves on a H. naledi endocast, like those in modern humans, lie farther back than the grooves seen in the chimp MRI scan, Hurst contends. Expanded tissue folds around those grooves also follow a distinctly humanlike pattern not observed [in] chimps, he argues. Those features indicate H. naledi had a humanlike capacity for pride and other complex social emotions and possibly verbal communication of some type, Hurst says. What’s more, the new study fails to consider that the A. sediba endocast shows furrows and folding patterns found in humans but not chimps, he says.

Endocast researchers need to study the range of brain surface characteristics in a larger sample of living chimps and other apes to make more accurate comparisons, Falk says. Until now, line drawings published in 1950 of only five chimp brain hemispheres, she notes, have provided the most accurate and comprehensive look at furrow patterns on chimps’ brains.

How specific folds and creases on the brain’s surface relate to inner structures, such as those involved in speech and language, also remains poorly understood, Falk says.

Can chimpanzee vocalizations reveal the origins of human language? While closely related to humans, researchers discover that chimpanzees’ vocalizations resemble human language less than you’d expect: here.

Chimpanzees (Pan troglodytes) appear to keep tidier sleeping arrangements than humans do. That’s one finding of a recent study that evaluated the microbes and arthropods found in the treetop beds that chimpanzees make each night: here.

An international team of scientists has studied the physiological parameters of savanna and rainforest chimpanzees and compared their water and energy budgets as well as their stress levels. They found that the stress of maintaining their body temperature is a tremendous burden on chimpanzees living in the savanna: here.

‘Chimpanzees more playful than gorillas’


This video from the USA says about itself:

How Do Chimps and Gorillas Play?

9 December 2014

In the second of three episodes with Lincoln Park Zoo, we learn about how the zoo promotes play at the Regenstein Center for African Apes.

From PLOS:

Adult chimpanzees play more than adult lowland gorillas in captivity

In adult animals, play is a sign of social cohesion and is inhibited by strong competition

March 7, 2018

Play is more frequent in captive adult chimpanzees than in captive adult lowland gorillas, according to a study published March 7, 2018 in the open-access journal PLOS ONE by Giada Cordoni and Elisabetta Palagi from Univerity of Pisa in collaboration with Ivan Norscia from University of Turin.

In many adult animals, play is thought to reflect a species’ degree of social cohesion, and is usually more frequent in species with low levels of competition and high levels of social affiliation. Cordoni and colleagues compared adult play in chimpanzees and lowland gorillas, two ape species with different social structures. Chimpanzees live in highly cohesive, co-operative groups that can have several adult males.

However, lowland gorilla groups are dominated by a single silverback male and have low levels of social affiliation. The researchers observed 15 chimpanzees and 11 gorillas in the ZooParc de Beauval, France. Altogether, observations were made over more than 129 hours for chimpanzees and 135 hours for gorillas, with play including “peek a boo” and “tug-of-war” games as well as “rough and tumble” play fights.

The researchers found that adult play was more frequent in chimpanzees than in gorillas, and play sessions lasted longer. In addition, in gorillas play was more likely to escalate into real aggression. It appeared that the more players, the more unstable a play session and the more difficult to manage. While future work will show if affiliative relationships really determine differences in social play amongst great apes, the researchers’ findings are in keeping with the differences in social structure of chimpanzees and lowland gorillas.

A study of the microbiomes of wild gorillas and chimpanzees offers insights into the evolution of the human microbiome and might even have implications for human health: here.

Bonobos, chimpanzees understand each other’s gestures


This 2015 video is called Chimpanzees & Bonobos – The Differences.

From PLOS Biology:

Bonobo and chimpanzee gestures overlap extensively in meaning

Kirsty E. Graham, Catherine Hobaiter, James Ounsley, Takeshi Furuichi, Richard W. Byrne

February 27, 2018

Abstract

Cross-species comparison of great ape gesturing has so far been limited to the physical form of gestures in the repertoire, without questioning whether gestures share the same meanings. Researchers have recently catalogued the meanings of chimpanzee gestures, but little is known about the gesture meanings of our other closest living relative, the bonobo.

The bonobo gestural repertoire overlaps by approximately 90% with that of the chimpanzee, but such overlap might not extend to meanings. Here, we first determine the meanings of bonobo gestures by analysing the outcomes of gesturing that apparently satisfy the signaller. Around half of bonobo gestures have a single meaning, while half are more ambiguous. Moreover, all but 1 gesture type have distinct meanings, achieving a different distribution of intended meanings to the average distribution for all gesture types. We then employ a randomisation procedure in a novel way to test the likelihood that the observed between-species overlap in the assignment of meanings to gestures would arise by chance under a set of different constraints.

We compare a matrix of the meanings of bonobo gestures with a matrix for those of chimpanzees against 10,000 randomised iterations of matrices constrained to the original data at 4 different levels. We find that the similarity between the 2 species is much greater than would be expected by chance. Bonobos and chimpanzees share not only the physical form of the gestures but also many gesture meanings.

Author summary

Bonobos and chimpanzees are closely related members of the great ape family, and both species use gestures to communicate. We are able to deduce the meaning of great ape gestures by looking at the ‘Apparently Satisfactory Outcome’ (ASO), which reflects how the recipient of the gesture reacts and whether their reaction satisfies the signaller; satisfaction is shown by the signaller ceasing to produce more gestures. Here, we use ASOs to define the meaning of bonobo gestures, most of which are used to start or stop social interactions such as grooming, travelling, or sex.

We then compare the meanings of bonobo gestures with those of chimpanzees and find that many of the gestures share the same meanings. Bonobos and chimpanzees could, in principle, understand one another’s gestures; however, more research is necessary to determine how such gestures and gesture meanings are acquired.

This research is important for getting to know about the common ancestors of bonobos, chimpansees and humans.

Jane Goodall and chimpanzees, new film reviewed


This video says about itself:

First Look at Jane | National Geographic

5 October 2017

Dr. Jane Goodall’s groundbreaking chimpanzee research redefined what it means to be human. Brett Morgen’s critically acclaimed film JANE will be released in select theaters starting Oct. 20.

Jane Goodall started her research without having any university degree: her family could not afford that. Before her work in Gombe in Tanzania, no one had ever properly studied wild chimpanzees. Goodall managed to get gradually closer and closer to the chimps, until they no longer saw her as a danger. This way, she managed to discover much about ape behavior never recorded before.

On 7 January 2018, I saw the film Jane, the 40th film ever about Jane Goodall, in a packed cinema. Much of the material is 1960s-1980s footage by Goodall’s first husband Hugo van Lawick; it was thought to have been lost, but was found again in 2014. Interviews with the main character, now that she is 83 years old, were added.

Before I write more about the movie, I have to go back 27 years; to something, not mentioned in the film, but relevant to its content.

In 1991, an article appeared in the New York Review of Books in the USA, written by Lord Zuckerman. The article claimed there were big, unbridgeable differences between humans and apes. One of the books reviewed in the article is Through a Window: My Thirty Years with the Chimpanzees of Gombe, by Jane Goodall. Lord Zuckerman attacked Ms Goodall for being supposedly ‘anthropomorphic’ about chimpanzees.

Who was Lord Zuckerman? Lord Solly Zuckerman (1904–1993) was a South Africa-born British zoologist and military strategist. I don’t know if he ever made any mistakes in military strategy. He certainly made major mistakes in zoology. More precisely, about Jane Goodall and chimpanzees, thirty years before his New York Review of Books article.

Lord Zuckerman, like most establishment scientists until the 1960s, believed there was absolute patriarchal male supremacy among chimpanzees. Jane Goodall’s research proved that theory was not completely right. One may argue that Zuckerman himself was ‘guilty’ of anthropomorphism. Though different anthropomorphism from what he accused Jane Goodall of, as he projected human patriarchal societies into the world of chimpanzees and other animals.

A 2014 interview with Jane Goodall mentions:

If her [Goodall’s] Cambridge colleagues had been patronizing, it was nothing compared to the treatment she received at a symposium on primates held at the Zoological Society of London in April 1962. “I gave my first scientific presentation and was terrified, says Goodall. “I practiced for hours,” she says. “I was determined not to read and not to say ‘er’ or ‘um.’ I have remained true to that ever since.”

After three days of talks, the meeting came to a close with a speech by Sir Solly Zuckerman, an anatomist who had studied monkeys in Africa, and gone on to become secretary of the Society and chief science adviser to the Ministry of Defence. Although Goodall had been well received, Zuckerman took the opportunity to fire a volley of pointed comments at the twentysomething newcomer.

“There are those who are here and who prefer anecdote—and what I must confess I regard as sometimes unbounded speculation,” he told his audience, as recounted in Dale Peterson’s biography of Goodall, The Woman Who Redefined Man. “In scientific work it is far safer to base one’s major conclusions and generalizations on a concordant and large body of data than on a few contradictory and isolated observations, the explanation of which sometimes leaves a little to be desired.”

On the morning of 7 January 2018, Dutch primatologist Jan van Hooff told Vroege Vogels radio about his memories of that meeting. Jane Goodall had discovered that chimpanzees use tools. And not only use tools: make tools. That contradicted the establishment science consensus that only humans use tools. Louis Leakey said Ms Goodall’s research made it necessary to redefine humans. If one defines a human as Homo faber, the tool user, then chimpanzees should be called humans as well (later discoveries found that not only chimpanzees but also other animal species make and use tools).

Jane Goodall also discovered that chimpanzees sometimes eat meat, hunting other animals.

Lord Zuckerman was livid, Jan van Hooff recalls. The noble lord stormed toward biologist Desmond Morris, who had invited Jane Goodall, and said: ‘Who has invited this stupid wench to talk nonsense here? Everyone knows that chimpanzees do not make tools. Everyone knows that chimpanzees eat only plants.’

Van Hooff and Morris responded politely, Van Hooff remembers. As it is not clever to sharply contradict a secretary of the Zoological Society of London who is a nobleman as well.

The 2014 interview says:

This was not Goodall’s first run-in with Zuckerman. At the end of 1961, there had been a press conference at London Zoo to announce her preliminary findings—and she had hatched a plan to use this public platform to call for an improvement in the conditions of the captive chimps at the zoo. “There was a bare cage with a cement floor,” she explains. During the summer months, the chimps had no shade: “It got boiling hot and there was only one platform, the other had broken, so the male got that and the female had to sit on the floor. It was horrible.”

Before the meeting, over dinner with the diplomat Malcolm MacDonald (who had visited her briefly in Gombe and would become governor-general of Kenya in 1963), Goodall shared her intention to champion the welfare of the captive chimps: “I was really excited.”

But MacDonald, with his experience as a politician, could see a flaw. Speaking out on behalf of the chimps to a packed auditorium would be a direct criticism of Zuckerman’s leadership of the zoo. “Do you think he’s going to allow a little whipper-snapper who doesn’t even have a degree to tell him he’s in the wrong?” Goodall recalls MacDonald telling her. “You’ll make an enemy for life, and you don’t want an enemy like that.”

Instead, Goodall suggested several simple changes to the chimps’ enclosure that would improve their welfare, and MacDonald worked behind the scenes to see them implemented. “What I learned then is: Don’t let people lose face, don’t try to do something publicly until you’ve tried every which way to do it quietly. I’ve found that so helpful to me”, she says …

Naturally, Zuckerman took the credit for the improvements to the chimps’ enclosure. “I don’t mind two hoots as long as it gets done”, Goodall says.

Decades later, Professor Jan van Hooff asked his Dutch biology students who knew who Lord Zuckerman was. Not one student’s hand was raised. Then, he asked who knew about Jane Goodall. All hands went up. ‘So, you see’, Van Hooff said.

The film shows how Jane Goodall went into the Tanzanian forest alone. How good she was at climbing trees. That she was not afraid of snakes, including poisonous snakes, as they usually don’t bite unless you step on them. That she got to know the chimpanzees better and better, starting the longest ever continuous research of wild animals, continuing till now. She recorded how chimpanzees were born, grew up and died. She differentiated between individual characters; another one of her innovations.

National Geographic sent Hugo van Lawick to Gombe to film and photograph her work. This brought Jane Goodall and ‘her’ chimpanzees to the cover of the magazine. Hugo and Jane fell in love; married; went to national parks like Serengeti together; got a son; and eventually divorced.

In 2009, Michael Barker wrote this criticism of Jane Goodall:

In October 2008 the world renowned primatologist and United Nations Messenger of Peace, Jane Goodall, traversed Australia, regaling packed houses with stories from her latest autobiographical book, Hope for Nature. Undertaking such whirlwind tours is the norm for Goodall. On average she spends some 300 days a year on the global lecture circuit to raise funds for her wide-ranging charitable activities. This gruelling schedule means that rather than conducting chimpanzee research, speaking engagements have tended to dominate her life over the past several decades. In an interview conducted last year by The Sydney Morning Herald she was asked what had prompted her to make this serious lifestyle change in the 1980s, Goodall replied:

Realising that chimpanzees were becoming extinct — the forests were going — and realising that the environmental and social problems of Africa could often be laid at the door of the elite communities around the world.

Yet despite recognizing that elites present a serious threat to the environment, she is adamant that the same elites will, with a little support from the public, provide the solutions to the very problems that they have created.

Bearing Goodall’s evidently optimist outlook in mind, it is fitting that she formerly served as a board member of the Humane Society of the U.S., a group that describes itself as “the nation’s largest… animal protection organization,” and is well supported by the elite community that Goodall apparently rails against. Here it is informative to point out that one particularly notable board member of the Humane Society is David Jhirad, who is currently the vice president for research and evaluation at the Rockefeller Foundation — an influential philanthropic group that happens to be a key democracy-manipulating organisation (see my earlier article “Pacifying Civil Society“). In addition to holding this influential position, Jhirad acts as the executive vice president of The Gemstar Group, an organisation that, according to their Web site, “work[s] with partners around the world in implementing market-based approaches to global environmental problems.” The president of The Gemstar Group, William Nitze, served as deputy assistant secretary of state for environment in the Ronald Reagan and George H.W. Bush administrations. …

Barker names other supporters of environment-destroying corporate capitalism, Big Oil corporation bigwigs etc. apparently trying to do ‘greenwashing‘ by associating with Dr Goodall’s pro-environment work. Work that apparently faces dilemmas like the WWF in Spain: which made King Juan Carlos its boss, only to discover that His Majesty killed elephants, and then having to sack him.

Barker concludes:

To surmise: the shady connections outlined within this article do not provide evidence to contradict the fact that Jane Goodall is a passionate and vocal orator on all things environmental. All the same, in spite of her evident passion, it seems more than probable that the message of hope that Goodall preaches worldwide is unlikely to promote environmental solutions that seriously challenge corporate power.

Maybe Ms Goodall’s 1961 experience of improving the London Zoo chimpanzees’ situation without a confrontation with the zoo establishment caused her to be over-optimistic on achieving change without confrontations with establishments. She supports the Green party in Britain; which sometimes does criticize the establishment, but sometimes does not go far enough in that.

Jane Goodall upset the scientific establishment and their wrong ideas. Unfortunately, she only partly sees through political and economic establishments and their wrong practices.

Anyone who peruses relationship settings on social media knows that our interactions with other humans can be intricate, but a new study in Nature: Scientific Reports suggests that researchers may be overlooking some of these same complexities in the social relations of our closest primate relatives, such as chimpanzees and macaques: here.

Bonobo apes help strangers


This video says about itself:

Susan Savage-Rumbaugh – The gentle genius of Bonobos. TED talks

7 April 2014

Savage-Rumbaugh’s work with bonobo apes, which can understand spoken language and learn tasks by watching, forces the audience to rethink how much of what a species can do is determined by biology — and how much by cultural exposure.

From Duke University in the USA:

Bonobos help strangers without being asked

Humans aren’t the only species eager to make a good first impression

November 7, 2017

Summary: The impulse to be kind to strangers was long thought to be unique to humans, but research on bonobos suggests our species is not as exceptional in this regard as we like to think. Famously friendly apes from Africa’s Congo Basin, bonobos will go out of their way to help a stranger get food even when there is no immediate payback, researchers show. What’s more, they help spontaneously, without having to be asked first.

A passer-by drops something and you spring to pick it up. Or maybe you hold the door for someone behind you. Such acts of kindness to strangers were long thought to be unique to humans, but recent research on bonobos suggests our species is not as exceptional in this regard as we like to think.

Famously friendly apes from Africa’s Congo Basin, bonobos will go out of their way to help strangers too, said Jingzhi Tan, a postdoctoral associate in evolutionary anthropology at Duke University.

A previous study by Tan and associate professor of evolutionary anthropology Brian Hare found that bonobos share food with strangers. Now, in a new series of experiments, the team is trying to find out just how far this kindness goes.

The researchers studied wild-born bonobos at the Lola ya Bonobo sanctuary in the Democratic Republic of Congo.

In one experiment, they found that bonobos will help a stranger get food even when there is no immediate payback.

Sixteen bonobos were led one at a time into one of two adjacent rooms separated by a fence. The researchers hung a piece of apple from a rope just above the empty room, visible but out of reach.

The apes couldn’t access the fruit or the rope. But if they climbed the fence they could reach a wooden pin holding the rope to the ceiling and release the dangling fruit, causing it to drop within reach of any bonobo that entered the next room.

The bonobos released the fruit roughly four times more often when an unfamiliar bonobo was in the adjacent room than when the room was empty.

What’s more, the bonobos didn’t wait to be asked for help, they just offered it. The researchers changed the size of the mesh surrounding the stranger’s room so that in some trials they were able to stick their arms through the openings in the screen to beg for the treat, and in other trials they were not. The bonobos helped just as often whether the stranger gestured for help or not.

Bonobos’ impulse to feel for strangers isn’t entirely under conscious control, the researchers also found. In another experiment, they had 21 bonobos watch a series of short videos. In some videos, the apes saw a familiar group member either yawning or making a neutral expression. In other videos they watched complete strangers from the Columbus Zoo in the U.S. behaving the same way.

Just as watching another person yawn can make you yawn, yawning is contagious in bonobos too. Previous studies suggest the phenomenon is linked to a basic form of empathy called “emotional contagion,” when one person’s mood triggers similar emotions in others around them.

The researchers found that stranger yawns were just as contagious as those of groupmates.

The impulse to be nice to strangers is likely to evolve in species where the benefits of bonding with outsiders outweigh the costs, said Tan, now a postdoctoral scholar at the University California, San Diego.

Female bonobos leave the group where they were born to join a new group when they reach adulthood, where they form bonds with other unrelated adults they’ve never met. Bonobos, like humans, may simply be eager to make a good first impression.

“All relationships start between two strangers,” Tan said. “You meet a stranger, but you may meet them again, and this individual could become your future friend or ally. You want to be nice to someone who’s going to be important for you.”

The results were published Nov. 7 in the journal Scientific Reports. This research was supported by the National Science Foundation (NSF-BCS-27552-02, NSF-BCS-10-25172).

By the age of three months, human babies can already follow Mr. Rogers’ advice to ‘look for the helpers.’ In fact, human infants naturally show a strong preference for individuals who help rather than hinder others. Now, a study finds that the same cannot be said of bonobos. While bonobos are similarly adept in discriminating helpers from hinderers, they show the opposite bias, consistently favoring hinderers over helpers: here.

Bonobos are willing to share meat with animals outside their own family groups. This behavior was observed in the Democratic Republic of the Congo and is documented in a new study: here.