Tag Archives: chimp


Wild chimpanzees learned how to crack open tortoises — and they’re sharing the knowledge among themselves

Turns out that you can teach an old chimpanzee new tricks — more to the point, they’ll teach themselves.


Image credits Simon Bardet.

A team of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig and the University of Osnabrück (both in Germany) report that wild chimpanzees in the Loango National Park, Gabon, have learned how to crack open and eat tortoise. The chimps will smash tortoises against tree trunks in order to get through their tough shells. This is the first time such behavior has been observed and, the team adds, it likely is a cultural one — meaning the chimps share this knowledge inside their groups and through generations.

Breaking their fast

“We have known for decades that chimpanzees feed on meat from a variety of animal species, but until now the consumption of reptiles has not been observed,” says Tobias Deschner, a primatologist at the Max Planck Institute for Evolutionary Anthropology.

“What is particularly interesting is that they use a percussive technique [i.e. smashing] that they normally employ to open hard-shelled fruits to gain access to meat of an animal that is almost inaccessible for any other predator.”

The team observed this behavior in the newly-habituated Rekambo community. Ten chimpanzees engaged in this behavior a total of 38 times over the dry season, the team explains, a period when other food such as fruit is abundant. Tortoise-whacking seems to be a highly social activity for the chimpanzees, the team explains.

“Sometimes, younger animals or females were unable to crack open the tortoise on their own. They then regularly handed the tortoise over to a stronger male who cracked the tortoise’s shell open and shared the meat with all other individuals present,” says Simone Pika, first author of the study and a cognitive scientist at the University of Osnabrück.

The authors also detail an exceptional case in which an adult male, who was sitting on his own up in a tree, cracked a tortoise, ate half, and hid the rest in a tree fork. The male climbed down from the tree, built his nest in another one nearby, then returned the next morning to eat the leftover tortoise. This particular case suggests that chimps can plan for the future, says Pika, which is quite an exciting find.

“The ability to plan for a future need, such as for instance hunger, has so far only been shown in non-human animals in experimental and/or captive settings. Many scholars still believe that future-oriented cognition is a uniquely human ability. Our findings thus suggest that even after decades of research, we have not yet grasped the full complexity of chimpanzees’ intelligence and flexibility.”

“Wild chimpanzee behaviour has been studied now for more than 50 years and at more than ten long-term field sites all across tropical Africa,” Deschner adds. “It is fascinating that we can still discover completely new facets of the behavioural repertoire of this species as soon as we start studying a new population.”

Pika says that chimpanzees offer a unique window into our own history, and that observing them in the wild can teach us a lot about our own evolution.

The paper “Wild chimpanzees (Pan troglodytes troglodytes) exploit tortoises (Kinixys erosa) via percussive technology” has been published in the journal Science Reports.

Bonobos, our closest relatives alongside chimps, seem have a similar disgust system to humans'. Credit: University of Kyoto.

Bonobos may get disgusted too — which may help trace the origin of this behavior in humans

Bonobos, our closest relatives alongside chimps, seem have a similar disgust system to humans'. Credit: University of Kyoto.

Bonobos, our closest relatives alongside chimps, seem to have a similar disgust system to humans’. Credit: University of Kyoto.

It’s not just humans that get grossed out by putrid stenches and moist textures — bonobos do it too. According to a new study, for these gentle primates, having access to clean food sources is important and they will generally stay away from grub in close proximity to feces, soil, or bad smells. We share 98.7% of our DNA with bonobos, more than we do with any other creature on Earth, which leads to many similarities between bonobos and humans. Perhaps, the origin of disgust might be traced back as a result of findings like these.


Isn’t it funny how we all share the same bodily and emotional reactions? That’s no accident as most can be traced back to some evolutionary adaptation. Scientists think that disgust is an adaptive system that evolved to protect animals from parasites and various pathogens, as a counter-strategy meant to mitigate infections. These threatening organisms often congregate in rotten food or bodily fluids, which we humans find repellent. The same reaction seems to exist in other animals. For instance, grazing ungulates prefer to feed away from areas contaminated by feces, and our primate cousins seem to employ similar strategies as well.

In 2017, researchers at the Primate Research Institute, Kyoto University, reported the first experimental evidence that potential exposure to biological contaminants (feces, blood, semen) can influence feeding decisions in chimpanzees (Pan troglodytes troglodytes). Now, the same team, led by primatologist Cecile Sarabian, has come to similar conclusions regarding bonobos (Pan paniscus).

The researchers carried out a series of experiments in which captive bonobos were presented with various food choices: food contaminated with feces or soil, chains of food items linked to a contaminant, previously contaminated food, or only the odors of feces or rotting food.

The bonobos were happy to eat the clean, uncontaminated food but stayed away from any contaminated food like it was the plague. The closer a foodstuff was to a contaminant, the stronger the repulsion. Conversely, when food was farther away from a contaminant, the primates’ sensitivity waned. “Some individuals just refused to take any food rewards when the latter involved contamination,” according to Sarabian.

In another experiment, the bonobos were found to be less likely to touch or taste substrates, or even to use tools to achieve such a goal, when confronted with foul smells. These are precisely the reactions that you would expect to see in an animal with a system of disgust set in place.

“These findings build up on the growing literature in primates and other animals, helping us to see convergences and differences in the disgust response across taxa at a behavioral and physiological level, as well as what may have driven such differences through evolutionary times,” Sarabian told ZME Science.

As a side note, it wasn’t quite easy setting up the experiments. Due to new sanctuary policies, the researchers were no longer allowed to perform the experiments on isolated subjects, which led to some unexpected outcomes.

“When I first started by presenting feces replica instead of real conspecific feces, bonobos gathered around and some bold individuals started touching it and sniffing their fingers just after. Then, it became a “thing”, they all wanted to touch and sniff the fake poop — not showing much interest for the piece of brown sponge used as the control. Eventually, after repetitive investigations, bonobos may have realized the trick and ended up stealing the fake poop… playing with it — Fieldwork FAIL!” Sarabian said.

Bonobos stayed away from foods in close proximity to feces. Credit: Kyoto University / Cecile Sarabian.

Bonobos stayed away from foods in close proximity to feces. Credit: Kyoto University / Cecile Sarabian.

Interestingly, infants and juveniles showed much less precaution when handling food close to contaminants, much like human infants behave. Although the infants might get sick as a result of this kind of behavior, the researchers hypothesize that there are some advantages like building their immune system during a critical time in their development.

Previously, Sarabian and colleagues also studied Japanese macaques, which also seem to elicit disgust responses.

“The most intense disgust response I ever witnessed across different field sites and species goes to a Japanese macaque from Koshima island, who accidentally stepped on a poop, and subsequently crossed all the beach jumping on her two hands and remaining foot to find a dead tree trunk where she meticulously rubbed her soiled foot,” Sarabian recounted.

Despite the similarities between human and bonobo disgust responses, there seem to be some key differences. We are pretty reluctant to ingest novel food that looks different from what we’re used to — that’s weird, basically. This kind of behavior — the inclination to stay away from or be cautious around new foods — is called neophobia but Bonobos don’t seem to share it, not at the same intensity at least. During experiments, bonobos stuffed themselves with fruits they had never seen before with no apparent sign of hesitation.

VIDEO: A plum, apple, and papaya were arranged in front of bonobos. Since apples are rare in this environment avoidance of it would indicate food neophobia. In fact the bonobos had not trouble eating each fruit, exhibiting food neophilia. At least for novel fruit. Credit: Kyoto University / Cecile Sarabian. 

As an important caveat, the researchers have not proven that bonobos express disgust, or not in a way that we can recognize, at least.

“Our results look as though the bonobos’ behaviors are driven by disgust, only because we know human behavior in similar situations is driven by disgust, but this is only a functional resemblance, and we cannot know what the bonobos are thinking or feeling at the time they are responding in our experiments,” co-author Andrew MacIntosh, Associate Professor at the University of Kyoto, wrote in an email.

That being said, the researchers plan on continuing to study bonobos and other primates with the intention of investigating the origins of disgust in humans. Sarabian is currently conducting fieldwork in the equatorial forest of the Democratic Republic of Congo, where she is investigating the link between mouthing behaviors and parasite infection in wild bonobos.

“The first step is to test whether the behavioral responses to things that humans find disgusting are similar in other species, like the bonobos tested here. Substances like feces and rotten foods are more or less universal disgust elicitors in humans, so we expect to see similar responses in nonhuman primates. If our responses to these things is seen in other species, it means that they likely have a shared evolutionary history that predates the appearance of humans. Furthermore, humans are pretty visual, so we expect that seeing disgusting things will elicit a ‘disgust response’. But we also know that we exhibit similar responses/feelings when we smell feces or rotten foods, so perception of ‘disgusting things’ is multi-modal,” MacIntosh said.

“Observing similar responses to disgust elicitors in other species, including through different sensory modalities like sight, smell, and touch, can assess whether our own responses are shared with other species,” he added.

The findings appeared in the journal Philosophical Transactions of the Royal Society B.


Caesar the chimp from 'Planet of the Apes'.

Though still stronger than humans pound-for-pound, chimps aren’t really ‘superstrong’

Caesar the chimp from 'Planet of the Apes'.

Caesar the chimp from ‘Planet of the Apes’ does not approve this message. Credit: 20th Century Fox.

Though they might not seem like much, chimps are stronger than humans — pound-for-pound of course. Actually, until not too long ago, chimps were thought of as ‘superstrong’, up to five times stronger than a human by some estimates. Recent work suggests there are only modest differences with humans in terms of sheer strength but our closest relatives still score better than humans on several measures. A new study headed by Matthew O’Neill, an anatomy and evolution researcher at the University of Arizona College of Medicine in Phoenix, reveals why — chimps have the most fast-twitch fibers.

Humans — the weakest of all great apes

The team performed biopsies on thigh and calf muscles collected from three anesthetized chimps housed at the State University of New York at Stony Brook. The samples were painstakingly separated into individual fibers then stimulated so the force they generate could be measured. This initial reading showed that the muscle output was about the same with that of humans, at an individual muscle fiber basis.

Another analysis was performed on muscle tissue harvested from the pelvic and hind limb muscles of three chimpanzee cadavers. Using a technique called gel electrophoresis, the team broke down the muscles into individuals muscle fibers and, again, compared the results with human muscle fiber data. They found was there was nothing special about chimp muscle. “Chimpanzee muscle is really no different than human muscle in terms of the force that individual fibers exert,” says O’Neill.

The analysis of the muscle fibers from the chimp cadavers, however, offered some clues as to why chimps are stronger than humans. Two-thirds of their muscle consists of fast-twitch fibers, whereas more than half of human fibers are slow-twitch. These are the two types of muscle fiber and fast-twitch fibers (myosin heavy chain II) contract very fast and generate more force in quick bursts than slow-twitch fibers. The downside is these fibers fatigue more quickly than MHC I. Chimps also seem to have longer fibers on average, which also enhances their strength.

“Our work is the first detailed study of the biology and mechanics of chimpanzee muscle tissue,” O’Neill told Gizmodo. “Our results show that the main difference between chimpanzee and human muscle is in fiber distribution, with chimpanzees having a much higher fraction of fast fibers than humans, on average,” adding that “all of our measurements of chimpanzee muscle are new.”

Later, data was run through a computer program that simulated the virtual muscles of human and chimps based on fiber composition. The model revealed chimp muscle is about 1.35 times more powerful than the human variety, as reported in the journal Proceedings of the National Academy of SciencesBut because humans are much heavier than a chimp, it’s safe to say that in absolute terms a typical human is more powerful than a typical chimp. There goes this myth, too.

” Thus, the superior mass-specific muscular performance of chimpanzees does not stem from differences in isometric force-generating capabilities or maximum shortening velocities—as has long been suggested—but rather is due in part to differences in MHC isoform content and fiber length,” the authors wrote.

O’Neill says it’s likely other apes have similar muscle strength to chimpanzees. Humans seem to be the odd ones. Indeed, when the team compared the muscle fiber in various mammals like mice, cats, dogs, horses or macaques, they found that only two animals had more slow-twitch fibers: the lethargic slow loris and humans.


Humans and distant cousins Slow Lorises are built for endurance…. Credit: Wikimedia Commons.

Fast-twitch fibers give mammals a competitive advantage when it comes to doing high-intensity tasks like climbing a tree or lifting a heavy bolder. We’re not feeble, though. Because we humans have more slow-twitch fibers, we’re better suited for endurance tasks like distance running, and during mankind’s great exodus out of Africa this certainly helped. Not to mention that human hunters could simply tire their pay around while hunting. Another benefit of slow-twitch fibers is they consume less metabolic energy, freeing energy that enabled humans’ bigger brains. Without this feature, you could say humans might have never come to conquer the world.

“We propose that the hominin lineage experienced a decline in maximum dynamic force and power output during the past 7–8 million years in response to selection for repetitive, low-cost contractile behavior,” the authors concluded.

[HEY, HUMAN, NOW GO READ] Are humans apes? 

Credit: Wikimedia Commons.

If you want a glimpse of an ancient human ancestor, the bonobo might be the closest you’ll get

Some eight million years ago, modern humans and the common chimp/bonobo lineages split. Since then, modern humans have evolved to look extremely different from this common ancestor and a new study suggests the bonobos have changed the least. In fact, bonobos have changed very little ever since they split again from chimps some two million years ago, hence scientists say the gentle bonobos serve as a remarkable case of evolutionary stasis.

Credit: Wikimedia Commons.

Credit: Wikimedia Commons.

A living ancestor

You often hear about how chimps share 99% of their genes with humans. That’s certainly true but chimps (Pan troglodytes) aren’t alone. In 2012, Max Planck scientists found bonobos (Pan paniscus) and chimpanzees share 99.6% of their DNA, despite the two species split some two million years ago, perhaps after the Congo River formed and divided an ancestral population into two groups.

But though chimps and bonobos share almost as much DNA with humans, Bernard Wood, professor of human origins at George Washington University, says the bonobos are the closest we are to a ‘living’ ancestor.

Wood and colleagues “carried out systematic dissections of cadavers of most extant primate taxa to gather evidence about how soft tissue – in particular striated muscle – gross morphology differs among living primates, with a focus on the great apes.” They were fortunate enough to have seven Bonobo cadavers donated by the Antwerp Zoo in the Netherlands. This was a very rare opportunity given bonobos’ status as an endangered species.

Armed with data from previous studies, the researchers made an anatomical comparisson between the muscles of the three species.

Differences between head muscles of common chimpanzees, bonobos and modern humans. There are many differences between bonobos and modern humans (right) concerning the presence/absence of muscles in the normal phenotype (shown in colors and/or with labels in the human scheme). Credit: George Washington University.

Differences between head muscles of common chimpanzees, bonobos and modern humans. There are many differences between bonobos and modern humans (right) concerning the presence/absence of muscles in the normal phenotype (shown in colors and/or with labels in the human scheme). Credit: George Washington University.

The study suggests there’s a mosaic evolution of the three species. In other words, some features are shared by humans and bonobos while others by humans and common cimpanzees, and still others by the two ape species. It might be no coincidence that this anatomical mosaical nature may be related to the similar molecular mosaic evolution betwen the three species. Bonobos share about 98.7% of their DNA with humans, roughly just as much as with the chimpanzee, but a small bit of our DNA, about 1.6%, is shared with only the bonobo, but not chimpanzees.

Ongoing debates might also be settled by the new data. Some have suggested bonobos are just highly derived chimpanzees but the present study refutes this idea. It shows bonobos do not display a single muscle or muscle feature that is unique within primate or hominoid evolution. Overall, however, the bonobo has more similar muscles to humans than chimpanzees have. This suggests that the bonobo is more closely linked, anatomically, to human ancestors than common chimpanzees.

Understanding how we’re different from our closest relatives will ultimately help us establish what makes us humans and will also lead to a better understanding of human health.

Scientific reference: Rui Diogo, Julia L. Molnar, Bernard Wood. Bonobo anatomy reveals stasis and mosaicism in chimpanzee evolution, and supports bonobos as the most appropriate extant model for the common ancestor of chimpanzees and humans. Scientific Reports, 2017; 7 (1) DOI: 10.1038/s41598-017-00548-3.

Chimps use dipping sticks to harvest water from tree holes. They’re the only ones that can reach the resource


Camera traps installed at the Comoe Chimpanzee Conservation Project in the Ivory Coast caught our closest relatives using tools in a new way for the first time. The clever chimps crafted dipping sticks by chewing one of the ends, turning a simple twig into a brush. The sticks are primarily used to harvest water from deep water holes. Only the chimps — and no other animal — seem to be able to access this kind of water resource, a clear competitive edge.

“The longer the brush, the more water they collect,” said Juan Lapuente, a lead researcher at the Comoe Chimpanzee Conservation Project.

Like humans, chimps use tool to make their lives easier. In 1960, Jane Goodall discovered that a chimp called David Greybeard would select twigs, strip their leaves, then use it to poke termite mound and collect the delicious insects. Since then, researchers have documented various other instances of tool use and, most strikingly, tool manufacturing. Josep Call from the Max Planck Institute for Evolutionary Biology in Germany said chimps who ‘fish’ for termites “complete tool manufacture by modifying the end into a ‘paint brush’ tip by pulling the stem through their teeth, splitting the probe lengthwise by pulling off strands of fiber, or separating the fibers by biting them.”

What’s more tool use and gestures are culturally based down, as documented by Dr. Catherine Hobaiter from the University of St. Andrews who witnessed how elder chimps in a community taught others how to use moss sponges to drink water.

Modified sticks remain the chimps favorite and most accessible tool. For instance, brush-tipped sticks are often used to harvest honey from bees’ nests, a practice common among many chimp populations in Africa. Sticks for accessing water, however, have only been witnessed in Comoe populations. This led the researchers to believe that these particular chimps have what they call a “drinking culture” — a practice shared among the group that helps them live through the dry season, as reported in the American Journal of Primatology.

Male chimps can be both players and good father, new study finds

Even though chimp dads really like to get down with members of the opposite sex, they still care about their offspring and are better dads than we thought

Image credits: USAID Africa Bureau (not related to this study).

Image credits: USAID Africa Bureau (not related to this study).


Chimps, humanity’s closest relatives, are highly promiscuous. Researchers previously believed that males are only interested in creating offspring and after that, it’s hands-off for them. Many biologists even doubted whether chimps can recognize their own offspring. But this is not the case – well, not necessarily.

Although dad chimps don’t spend that much time with their offspring, they do spend time with females who take care of their offspring. Initially, the hypothesis was that they want to mate with these females because they are good carers, but this was disproven with 25 years of behavioral data gathered by the Jane Goodall Institute and digitized at several universities and research centers.

The data indicates not only that chimps can recognize their offspring, but they are invested in their wellbeing – both directly and indirectly. Chimp dads also spend more time grooming and looking after their offspring than many believed.

“Our findings are not only further evidence that chimpanzee fathers recognize their offspring in a promiscuous species, but also that fathers behave differently around their offspring,” said Margaret Stanton, postdoctoral scientist at GW’s Center for the Advanced Study of Human Paleobiology and co-author of the paper.

This study could be significant not only for chimps, but for humans also. Chimps are our closest living relatives, and understanding how their paternal behavior evolved could help us understand our own behavior more.

“As anthropologists, we want to understand what patterns could have existed early in human evolution that help explain how human behavior evolved,” said Carson Murray, assistant professor of anthropology at the George Washington University and lead author of the paper. “This research suggests that males may sometimes prioritize relationships with their offspring rather than with potential mates. For a species without pair-bonds where it was assumed fathers didn’t know which infants were their own, this is an important finding.”

However, this is still only a piece of the anthropological puzzle. Human dads exhibit very different behaviors, and in today’s world, societal impact is likely much stronger than the biological impact.

Journal Reference: Carson M. Murray, Margaret A. Stanton, Elizabeth V. Lonsdorf, Emily E. Wroblewski, Anne E. Pusey. Chimpanzee fathers bias their behaviour towards their offspring. Royal Society Open Science, 2016; 3 (11): 160441 DOI: 10.1098/rsos.160441

Chimps interbred with bonobos, surprising study reveals

Just like early humans interbred with Neanderthals, it seems that our closest relatives also had some fun times with each other. According to a new genetic analysis, one percent of the chimpanzee genome comes from bonobos.

Chimps and bonobos are the only two species in the genus Pan and they represent our closest genetic relatives. Both species inhabit the Congo jungle in sub-Saharan Africa, and in some areas their habitats are really close to each other – though separated by the Congo river. Despite being intelligent and exhibiting several human traits, they are endangered and often hunted or kept as captives. This is the main reason why the study was carried out – not to identify connections between the two species, but to help preserve the chimpanzees.

“This is the largest analysis of chimpanzee genomes to date and shows that genetics can be used to locate quite precisely where in the wild a chimpanzee comes from,” said Dr Chris Tyler Smith, from the Wellcome Trust Sanger Institute.

“This can aid the release of illegally captured chimpanzees back into the right place in the wild and provide key evidence for action against the captors.”

Still, the research did yield some interesting biological info. Researchers found that the two species diverged from a common ancestor between 1.5 and 2 million years ago. But some chimp populations had a surprise: bonobo DNA embedded in their own genes.

“We found that central and eastern chimpanzees share significantly more genetic material with bonobos than the other chimpanzee subspecies. These chimpanzees have at least 1% of their genomes derived from bonobos. This shows that there wasn’t a clean separation, but that the initial divergence was followed by occasional episodes of mixing between the species.

Many biologists didn’t even consider interbreeding between the two species so this came as quite a surprise, but the results are pretty clear. There is a clear resemblance between what study on our own species have found — early humans and Neanderthals diverged from the same ancestor, but they also interbred for a long time. Non-African humans carry within them a significant part of Neanderthal DNA. Dr Tomàs Marquès-Bonet, leader of the study from the Institute of Biological Evolution (University Pompeu Fabra and CSIC), Barcelona, said:

“This is the first study to reveal that ancient gene flow events happened amongst the living species closest to humans — the bonobos and chimpanzees. It implies that successful breeding between close species might have been actually widespread in the ancestors of humans and living apes.”

Journal Reference: Chimpanzee genomic diversity reveals ancient admixture with bonobos. Science, 2016; 354 (6311): 477-481 DOI: 10.1126/science.aag2602

This is Reo sitting up by grasping ropes after lying on his back for 14 months following the onset of acute tetraparesis. Credit: Primate Research Institute, Kyoto University

How a touch screen helped a disabled chimpanzee walk again

This is Reo sitting up by grasping ropes after lying on his back for 14 months following the onset of acute tetraparesis. Credit: Primate Research Institute, Kyoto University

This is Reo sitting up by grasping ropes after lying on his back for 14 months following the onset of acute tetraparesis. Credit: Primate Research Institute, Kyoto University

In 2006, Reo the chimp became paralyzed from the neck down due to a spinal chord inflammation. But the chimp fought back and was able to recover enough to stand up and, later, pull himself upright using suspended ropes. There was still a matter of regaining the function of his legs, though. Gently and with a lot of patience, researchers of the Primate Research Institute at Kyoto University devised a novel physiotherapy that enabled Reo to walk using his feet ten years later.

Like most chimps from the Institute, Reo is well versed in using a touch screen to solve cognitive tasks. As a reward, he would receive a tasty treat. Although Reo had not used touch screens following his disability, Yoko Sakuraba of Kyoto University and colleagues tried using computerized tasks to help the chimp regain the function of his legs.

The setup was very simple. A tablet computer was placed on the surface of a wall in the lab where Reo had to perform some cognitive tasks, just like the old days. But instead of having the reward readily served after the task was ever, the food was placed on a tray in the opposite end of the room.

Final layout of the rehabilitation room. White represents the area used by humans, and grey represents the area used by the chimpanzee. a Thin lines represent walls made of acrylic board and iron frames, bold lines represent walls made of concrete, and dotted lines represent wire grid walls or partitions. Credit: Journal Primates

Final layout of the rehabilitation room. White represents the area used by humans, and grey represents the area used by the chimpanzee. a Thin lines represent walls made of acrylic board and iron frames, bold lines represent walls made of concrete, and dotted lines represent wire grid walls or partitions. Credit: Journal Primates

At first, the chimp would not cooperate, but the researchers were just as stubborn. They changed the setup seven times until Reo was comfortable enough to attempt to solve the puzzles on the computer screen. And so Reo ended up completing multiple tasks, then moved two meters to pick his food, only to move two meters more to return to his station.

During his first travel, the chimp moved by clinging to a stationary rope, but gradually Reo learned to move in an upright seated position which resembled the side-to-side manner of a penguin walking on land. After many, many rehabilitation sessions Reo was eventually able to walk for up to 500 meters during two-hour long sessions.

“Cognitive tasks may be a useful way to rehabilitate physically disabled chimpanzees, and thus improve their welfare in captivity,” says Sakuraba.

The story is indeed touching because it shows our primate cousins have at least just as much determination to regain bodily functions as humans do. This is important because it shifts the animal care paradigm, which in such situations advises euthanasia. Dr. Sakuraba says many disabled primates, and perhaps non-primates too, could use this treatment aided by humans to regain movement. She cautions, however, that just like for humans, this operation needs to be custom tailored to the needs and personalities of the patient.

“This study successfully applied a new method of walking rehabilitation using cognitive tasks to a chimpanzee with hind-limb disabilities. In particular, total distance walked increased, and the chimpanzee voluntarily participated in the process. Though Reo initially appeared fearful of the touch monitor and stopped several times during the walking rehabilitation sessions, careful adjustments resolved this problem, leading to the conclusion that personality and physical condition need to be considered when designing and adjusting a rehabilitation program. In addition, this was the first successful rehabilitation method to encourage walking and customized for a chimpanzee, Reo. In the future, we will need to continue rehabilitation exercises, and discuss goals for his continued improvement and well-being,” the authors wrote in the Journal Primates. 

Do chimps have accents? New research casts doubt on it

A study published by British researchers caused a storm among biologists; the question on everyone’s lips – do chimps have accents?

Sophie Pearson / University of York

Initially, a group of eight researchers studied a group of chimps moved from a Dutch safari to a Edinburgh Zoo in Scotland, concluding that the primates can replace the vocal sounds their native group used for objects, in this case apples, with those of their new group. In other words, they are able of vocal learning and adaptation and can develop their own accent. But not everyone is convinced.

“There are a number of problems with the original study,” said Dr James Higham, from New York University. “Some of these relate to the methods used, while others are fundamentally a misrepresentation of what the data actually show.”

Dutch chimps used a high-pitch to denote apples, but after three years in Edinburgh, they switched to the lower pitch that the Edinburgh chimps use. This seems logical, but the data set is very limited. Another team re-analyzed the results, and came up with a different, more conservative conclusion.

“This was a pretty drastic example of exaggerated claims based on a thin data set,” Fischer said. “Some people are more happy to accept a wild explanation. Others aren’t.”

Dr Simon Townsend from the University of Warwick, who co-wrote the original study with colleagues in York and St Andrews said that it’s normal for this type of things to happen – it’s how science works – but he refuted the new claims.

“We think that we’ve addressed the points that they bring up. It’s an interesting critique of our research – and this is exactly how science works.”

It will take quite a while before the dust settles and the scale weighs in one way or another – or it may never do, at least not in the near future. But it does highlight a very important aspect: if you want to make bold claims, you need serious evidence to back it up. The initial study may be right, but its conclusions are still debatable – and there’s nothing wrong with it; if anything, it’s the mark of healthy science.


Chimps enjoy the movies just as much as we do

A video of an ape, breaking out of its cage and attacking; the victim — a human scientist, that picks up a small red hammer and defends himself, battering the primate ran amok.

It sounds like a pretty gruesome video, bound to have animal right’s activists redouble their efforts to see the heartless jailers brought to justice. But hey, wait a minute… Apes don’t wear sneakers.

What gives?

The 40-second dabble into homemade horror by researchers in Japan was presented to an engaged crowd of chimp viewers as part of a study published in Current Biology. The team found that not only did the chimps fail to avert their eyes, but were not tempted by distracting treats dangled in front of them during the screening.



Then the team tried playing the video to them 24 hours later, and the chimps actually remembered where the hammer was, and the role it played — their eye movements show they watched the impromptu weapon several times before it was actually picked up. This suggests that the chimps remembered the plot and were expecting the hammer to be picked up.

The rights of simians are currently being debated in the US, with some lawyers arguing chimps are “autonomous and self-determining” beings. Such issues have long been chewed over at the movies, with the rebooted Dawn of the Planet of the Apes franchise recently reigniting discussion. Earlier this year, Jurassic World and Ted 2 both also cheerled for some animals to enjoy equivalent rights to humans.

Ancient shoulders point to our ape past

A new study shows that evolution’s burden is distinctly visible on our shoulders – literally. Our shoulders are surprisingly similar to those of orangutans, as opposed to those of our closest relatives, chimps. This allowed us to be better throwers but also made us more prone to injuries.

A hypothesized model of shoulder shape evolution from African ape-like (top left) to modern human (bottom right) including predicted ancestral forms (grey) and hominin fossils: Australopithecus afarensis (DIK 1-1 developmental simulation, top right), Australopithecus sediba (MH2, middle left), Homo ergaster (KNM WT15000, middle right), Homo neanderthalensis (Kebara 2, bottom middle). Credits: Nathan Young.

Humans started splitting from other species in the Pan genus some 6-7 million years ago. The genus Pan is part of the subfamily Homininae, to which humans also belong. In many ways, we are today similar to chimps. Classic research by Mary-Claire King in 1973 found 99% identical DNA between human beings and chimpanzees, although today that number is believed to be closer to 94%; in genetic terms, we are almost identical to chimps, and many similarities are easy to see. However, when it comes to shoulders, we’re more like our distant cousins the orangutans: less suited for climbing and better at handling tools and throwing things.

“Humans are unique in many ways. We have features that clearly link us with African apes, but we also have features that appear more primitive, leading to uncertainty about what our common ancestor looked like,” said Nathan Young, PhD, assistant professor at UC San Francisco School of Medicine and lead author of the study. “Our study suggests that the simplest explanation, that the ancestor looked a lot like a chimp or gorilla, is the right one, at least in the shoulder.”

Human shoulder blades are built for labor and not climbing, but 3D scans of shoulder blades from humans, early-human ancestors, apes, and monkeys alike seem to indicate that all of them are similar enough to suggest that we evolved from an ape model. According to researchers, it took quite a while for us to adapt from a tree-based life to moving on the ground and using tools, but we did adapt, and so did our shoulders (in time).

“These changes in the shoulder, which were probably initially driven by the use of tools well back into human evolution, also made us great throwers,” study author Neil T. Roach, a fellow of human evolutionary biology at Harvard University, said in a statement. “Our unique throwing ability likely helped our ancestors hunt and protect themselves, turning our species into the most dominant predators on earth.”

The study started with the class “That’s odd…” statement. Researchers realized that the human shoulder is strange.

“Human shoulder blades are odd, separated from all the apes. Primitive in some ways, derived in other ways, and different from all of them,” Young said. “How did the human lineage evolve and where did the common ancestor to modern humans evolve a shoulder like ours?”

To figure this out, they studied two early human Australopithecus species, the primitive A. afarensis and younger A. sediba, as well as H. ergaster and Neandertals, to build up a sort of shoulder spectrum and see how everything fits.

“Finding fossil remains of the common ancestor would be ideal, however, when fossils are absent, employing such multifaceted techniques is the next best solution,” said Zeray Alemseged, PhD, senior curator of Anthropology at the California Academy of Sciences.

But even with the resources they had available, they were able to establish the relationship between the different shoulders.

The switch came with a bunch of trade-offs, both positive and negative. For starters, human shoulders are better at throwing things fast and precise, which certainly helped our ability to hunt. However, this also left us more prone to shoulder injuries, which is still visible today. Americans get approximately 2 million rotator cuff injuries each year. Actually, this research could help those suffering from this type of injuries:

“We could potentially use information about the shape of an individual’s shoulder to predict if they have a higher likelihood of injury and then recommend personalized exercise programs that would best help to prevent them,” Young said. “For a baseball pitcher, depending on your shoulder shape, you might want to emphasize some strengthening exercises over others to protect your rotator cuff.”

Photo: The Shark Guys

Some chimps like to drink alcohol habitually. “So, a chimp walks in a bar…”

It’s nothing new to hear about chimps or monkeys drinking alcohol, most often stolen from unsuspecting tourists, but a new research which documented the chimpanzees of Bossou, south-eastern Guinea, for the past 17 years found some engage in habitual drinking. It’s the first evidence of habitual drinking outside humans. Like humans, some enjoy the brew more often than others, while some totally abstain from the habit.

Photo: The Shark Guys

Photo: The Shark Guys

From 1995 to 2012, the West African chimps were watched and recorded using cameras by researchers as they went about their daily habits. Apparently, many chimps would regularly visit the local  raffia palms. Humans in the area harvest the sugary sap from the trees to brew alcohol. They typically make a tapered section in the tree, then put some containers underneath to let the white sap slowly ooze in containers placed right below. Within hours, the sap ferments into alcohol, and one single tree can yield up to 50 liters of sap in a year. But the chimps have caught on.

The containers that hold the sap are usually covered with large leaves. Some chimps would go to these seemingly self-replenishing hot spots, chew the leaf a bit until it turned into a sponge-like pad then used it to dip into the container and drink the sap. In the same community, sometime in 2008, one of the chimps used a stick to “fish” for ants, a sophisticated display of tool use. When they have to, apparently chimps also know how to fashion tools that help them get drunk. Though the researchers didn’t directly sample blood to see how much alcohol they’d ingested, the researchers believe some of them got quite “ape” drunk. On one occasion, after he had copiously sipped from the container, a chimp went directly to rest and went sound asleep. Another adult male seemed restless after a drinking session and while his companions made for their nests, spent the next hour swinging from tree to tree.

The fermented sap has an alcohol content ranging from  3.1 per cent to a whopping 6.9 per cent (the equivalent of a strong beer). It takes like cider.

Now, reports of animals getting drunk don’t come as a surprise anymore and make for tear-jerking cheap entertainment on YouTube. This includes Swedish moose that get drunk on fermented apples, or green monkeys stealing tourists’ cocktails in the Caribbean. However, habitual drinking has never been reported so far. In their paper published in  Royal Society Open Science, the researchers at  Oxford Brookes University outline how both male and female chimps engage in regular sap drinking sessions. Some drank more than others. Of 26 apes followed in the report, one chimp named Foaf was the most apt drinker appearing  in 14 of the 51 sessions. But not all of them were that interested, since 13 chimps in the group never partook.

The findings bear a larger significance than just “humanizing” chimps. Humans, like all primates, use the alcohol dehydrogenase enzyme ADH4 to metabolize alcohol. Yet, not all can metabolize alcohol just as well. Lemurs and baboons, for instance, have a less effective version of ADH4, which raises the question: when did humans actually evolve this highly active version of the enzyme? A recent research performed a thorough genetic analysis of primate samples, traced these ancient proteins and found the earliest version of ADH4 dated as far back as 50 million years ago. During this time, however, ADH4 was only able to metabolize minute amounts of alcohol. Some 10 million years later, though, ADH4 could metabolize 40 times more ethanol. So, where do the drinking chimps come in? Well, there’s this theory that our early ancestors, still mostly tree dwelling at that time, would sometimes eat fallen fermented fruit fallen on the ground. Natural selection favored those ancestors which got less drunk (more effective ADH4) while eating more fruit. So, both humans and chimp have those pioneers to thank for their ability to drink alcohol.

Does anyone remember the ol’ chimp in the bar joke? So, a chimpanzee walks into a bar and sits down, while the bartender is approaching him. The bartender, thinks he can make some easy money from this chimpanzee. So the bartender asks the chimpanzee what he would like for a drink, the chimpanzee says he would like a beer. Upon bringing the beer the bartender says: “That would be 25 dollars”. The chimpanzee pays and enjoys his beer.

The bartender, still amazed by the fact that there’s a chimpanzee in the bar, decides to make some small talk with him. So he starts talking to the chimpanzee: “A chimpanzee! You don’t see that often in a bar..” The chimpanzee looks up and says: “What do you think, one beer costs 25 dollars!

Now, that’s not so absurd as it may seem. For one, chimps might enjoy beer. Secondly, if some monkey can learn how to use money, so could chimps.

Chimps cook if given the chance, study shows

Chimps not only have the brain power to understand the concept of cooked food, but they are willing to delay eating raw food if they know it can be cooked. This highlights impressive cognitive abilities, such as the foresight and patience to resist their urge of eating food..

Image via PBS.


Don’t expect the primates to start competing against Gordon Ramsay, but they just love roasted potatoes. Scientists noticed that chimps would give up a raw slice of sweet potato in the hand for the prospect of a cooked slice of sweet potato a bit later. That kind of self control came as a surprise initially.

“Many primate species, including chimpanzees, have difficulty giving up food already in their possession and show limitations in their self-control when faced with food,” the Harvard researchers who conducted the study note.

Sure, chimps lack the technical abilities to cook, but if they are given the necessary tools (an oven) they “might be quite able to manipulate (it) to cook,” said developmental psychologist Felix Warneken of Harvard University, who conducted the study with Alexandra Rosati. An experiment showed that when given a functional oven and a non-functioning oven, chimps always placed the potatoes in the functioning one – in other words, they preferred cooked potatoes. It was already known that chimps prefer cooked food, so researchers took things one step further: they gave the chimps raw potatoes; before they were shown the concept of cooking, they simply took the potato and ate it, but once they had been introduced to cooking, they chose not to eat it wait for it to be cooked.

“The first time one of the chimps did this, I was just amazed,” study co-author Alexandra Rosati who is moving to Yale University said. “I really had not anticipated it. When one of them did it, we thought maybe this one chimp is just a genius, but eventually about half of them did it,” Rosati pointed out.

Aside for the chimps’ abilities, this also suggests that cooking emerged early in human evolution. The earliest archaeological evidence of cooking is about 1 million years old, but in light of this discovery, it may be that cooking emerged when humans had the mental abilities of today’s chimps, about 2 million years.

“What is particularly interesting about cooking is it’s something we all do, but it involves a number of capacities that, even without the context of cooking, are thought to be uniquely human. That is why we wanted to study this in chimpanzees,” explained Felix Warneken from Harvard University.

The research was inspired by the work of Richard Wrangham, an anthropologist at Harvard and several colleagues about 15 years ago in an article in Current Anthropology. Wrangham went on to describe his findings in a book, “Catching Fire: How Cooking Made Us Human.” He too argued that cooking evolved around 2 million years ago.

As for the chimps, Warneken believes that they would be able to operate a simple oven, and they have the causal understanding.


Handy women: females are better than male at DIYs – at least in chimps

In most cultures, men are typically regarded as handy and it’s usually up to them to do the handy work – it’s quite a stereotype actually, but I think it’s among the few that really stick; but a new study reveals that women may actually be much more well suited for that job. Female chips were observed building and using tools much more than their male counterparts, who prefer to catch the prey with their bare hands.

Image credits: Tambako the Jaguar

While chimps throughout the world use tools to get at termites and tubers (again, mainly females), only the Fongoli chimps are known to use weapons to hunt their prey. In 2007, Jill Pruetz from Iowa State University in Ames discovered that chimps in Fongoli, Senegal, thrust sharpened sticks into nest holes in trees to stab or club small, nocturnal primates called bushbabies. She also noted that even though there were fewer females than males in the hunting party, they seemed to do most of the job.

“In a number of primate species, females are the innovators and more frequent tool users, so I think it is possible that a female invented this technique,” Pruetz said.

Now, in another study, she and her team found that females are still dominant when it comes to using tools in hunting. If this happened in chimps, then does this means it also happened in early hominids? Were the archetypal hunters actually female?

“Maybe it should cause people to rethink the old premise of man the hunter,” she says.

Those are still valid and open questions. It seems to be very likely that females actually initiated weapon-based hunting, but it quickly became a male thing. Travis Pickering of the University of Wisconsin at Madison seems to agree:

“Maybe the initial inventiveness is female-based,” says Pickering. “But I don’t think we’ll ever be able to pin that down based on archaeological data.”

While relevant archaeological evidence does seem almost impossible to gather, anthropological observations in chimps provide a good window into how early hominids may have evolved. If the same thing applies to humans, then one question still remains: Why do I always have to fix the sink ?


Chimp gesture language translated – they’re the only ones besides humans to intentionally communicate

If you’ve ever watched chimps during a nature program and became startled by your own empathy towards them, you’re not alone. It’s no secret that chimps are our closest relatives out of all primates, having 98% similar DNA. It goes further than genetics – it’s enough to look a chimp in the eye. The reflection is more than a physical mirror; there’s a connection, and a recent study shows yet again how ‘human’ chimps can be. After closely following chimps for thousands of hours, British researchers finally cracked chimps’ communication code. The result: we now have a dictionary of 66 chimp gestures, often and dynamically used by the primates to intentionally convey meaning to one another.  This might just be one of the most important contributions in animal behavior and biology in a long time.

Chimp sign language

The researchers analyzed more than 5,000 meaningful exchanges between chimps, before they could settle on the most defining ones. Some of these gestures are unambiguous – used consistently to convey one meaning. Not surprisingly, some are very subtle. A chimp clipping a leaf, for instance, is eliciting sexual attention from a potential mate. Other gestures are ambiguous and have different meanings depending on the context. When a chimp grabs another chimp, he communicates “Stop that,” “Climb on me,” or “Move away,” depending on the situation.


A while ago, researchers showed that the gelada – a primate that closely resembles the baboon – can howl in a distinct manner mirroring human speech in some respects. Other research showed that monkeys and apes can understand complex information from another brethren’s call, but chimps are the only animals that intentionally communicate through gestures, apart from humans.

“It’s a bit like if you pick up a hot cup of coffee and you scream and blow on your fingers,” Dr Catherine Hobaiter, Professor at University of St. Andrews, who led the research,

“I can understand from that that the coffee was hot, but you didn’t necessarily intend to communicate that to me.”

What makes you human?

So, if you had any doubts until now that there are other beings in this world (no aliens!) that share some of your emotions, and actually communicate these feelings, you have to look no further. Really, we’re not all that different. But this isn’t the end of it. Most likely, chimps use more commonly accepted gesture to communicate, and this need documenting. Also, it would be interesting to see how gestures evolve in a chimp community. After all, chimps seem to have fashion fads too. There’s no telling how truly complex and dynamic chimp society is.

“I have the impression that there were some meanings we couldn’t capture,” Hobaiter said. Sometimes, she recalled, a chimpanzee would gesture to another, then appear satisfied, though nothing else seemed to happen. Said Hobaiter, “I’d love to know what was going on!”

The chimp lexicon was described in a paper published in the journal Current Biology.


Brent is 37 years old and has lived at Chimp Haven in Keithville, La., since 2006. Brent paints with his tongue.(Photo: Humane Society of the United States)

Abstract art painted by chimps to be auctioned. Raises awareness on lab cruelty

The Humane Society of the United States (HSUS), recently initiated a bold and creative project in which they enlisted six member organizations of the North American Primate Sanctuary Alliance. HSUS asked the organizations if they would each submit a piece of art made by chimps belonging to their respective sanctuaries. In the end, some pretty creative and expressive pieces of art were submitted. The winning piece was authored by the most eccentric of the chimp artists, being painted through a technique using the tongue only.

Brent's award-winning painting.(Photo: Humane Society of the United States)

Brent’s award-winning painting.(Photo: Humane Society of the United States)

The winning entries were chosen only last week, after more than 27,000 people voted their favorites online, and topping the list was the art made by Brent, a 36-year-old chimp who paints only with his tongue. His sanctuary, Chimp Haven of Louisiana, won a grant of $10,000 from The HSUS. Jane Goodall, famed primatologist and U.N. Messenger of Peace, was also part of the judging panel.

“All of the art was beautiful and unique, just like chimpanzees!” Goodall said. “It was difficult to choose. It’s so important that the public support all of these sanctuaries in their mission to provide exceptional care to chimpanzees, and other primates, who have suffered through so much.”

Cheetah, of Save the Chimps in Florida,  came in at second with his meticulous work. His entry was also Goodall’s favorite out the bunch. The chimp’s sanctuary was awarded $10,000.Ripley of the Center for Great Apes in Florida won third prize, for a $2,500 grant, followed by paintings by Jamie of Chimpanzee Sanctuary Northwest, Jenny of Primate Rescue Center, and Patti of Chimps, Inc., convey the unique style of each chimpanzee.

Second prize entry made by Cheetah, who lived alone in a lab for 13 years and endured more than 400 biopsies before being rescued by Save the Chimps. (c) Save the Chimps

Second prize entry made by Cheetah, who lived alone in a lab for 13 years and endured more than 400 biopsies before being rescued by Save the Chimps. (c) Save the Chimps

There’s more to the project than just showcasing cute and amazing chimpanzee art or rewarding the sanctuaries that care for them. The project seeks to raise awareness on the dire conditions these chimps were forced to  during their past ‘careers’ as research chimps or in the entertainment industry.  Brent, Cheetah, Jenny and Jamie were all used in biomedical research. Cheetah had it the worst of all – 19 years of medical research and in that time had more 400 liver biopsies, according to his sanctuary, Save the Chimps in Fort Pierce, Fla., which is home to 261 chimpanzees.

Third prize entry by Ripley. Like many chimpanzees used as actors, Ripley was eventually dumped in a roadside zoo. There, he witnessed the shooting death of his brother and two other chimp companions after human error resulted in the chimpanzees’ escape. Ripley found sanctuary at Center for Great Apes and impresses his caretakers with his resilience and forgiveness.

Third prize entry by Ripley. Like many chimpanzees used as actors, Ripley was eventually dumped in a roadside zoo. There, he witnessed the shooting death of his brother and two other chimp companions after human error resulted in the chimpanzees’ escape. Ripley found sanctuary at Center for Great Apes and impresses his caretakers with his resilience and forgiveness.

Recent advances in medicine, like in-lab culturing of organs from adult stem cells and computer models have significantly reduced the number of research on chimps – ideal animal models since they share 98.5% of their DNA with humans. Still, there are many yet employed in research. In all good faith, most scientists appreciate, while admitting research made on them is cruel, that the chimps are still indispensable to research of treatments that could save thousands if not in some cases millions of lives.

The National Institutes of Health is set to retire more than 300 chimpanzees soon, while the U.S. Fish & Wildlife Service has recently proposed the listing of chimps as endangered under the Endangered Species Act. If the proposal passes, then chimps would be out of the labs for the good.

As for the artworks, these will be auctioned off and the proceeds will benefit the North American Primate Sanctuary Alliance .

 “We cannot thank these sanctuaries enough for providing their chimpanzee residents with such peaceful and enriching lives. They deserve the public’s support for the amazing work they are doing and will continue to do as hundreds more chimpanzees make their way to retirement after decades in laboratories,” said Kathleen Conlee, vice president of animal research issues at the HSUS.

You can view all of the entries here.


Chimps also ‘think about thinking’ akin to humans


Our close primate relatives, chimpanzees, have been constantly amazing us with their incredible cognitive abilities and personality traits that are so similar to our own. If you believe much of what you undertake today is limited to human cognition only, think again. Chimps do it too – thinking about thinking that is, as the findings of a recent research by scientists at Georgia State University and the University at Buffalo show.

Chimps are our closest relatives, sharing 98% of the human genome, which might explain a bit why their social, cognitive and even emotional display is remarkably similar to that found in humans. Chimps have been shown to be self-aware (possess consciousness), have a sense of fairness, solve puzzles just for fun and even hold elections!

That’s remarkably human-like, however this recent demonstration of chimp metacognition – “thinking about thinking” or “knowing about knowing” – puts things into a whole new perspective.  Though a term that’s both thrown loosely in educational psychology discussions and discouraging at the same time, since not a lot of people know what it means, metacognition in itself represents nothing new, but highlights an important hallmark of intelligence. It’s believed metacognition plays a fundamental role in learning, since it’s only when you begin to rationalize your train of thought that you can begin to control what goes on in your environment and project your thoughts into actions. Activities such as planning how to approach a given learning task, monitoring comprehension, and evaluating progress toward the completion of a task are metacognitive in nature.

Existential chimps

In order to assess a chimps ability to recognize one’s own cognitive states, the researchers devised an experiment to query animals about their states of knowing or not knowing. Chimps at Georgia State’s LRC, like some in other labs, have been trained  to use a language-like system of symbols to name things, which came really handy later on in communicating their thoughts and ideas.

The chimps were tasked with naming which food was hidden in a particular location, by typing the symbol for the respective type of food. For instance, if a banana was hidden, the chimp would report this fact by pressing the banana symbol on symbols keyboard, and in the process would also gain the food.

But then, the researchers provided chimpanzees either with complete or incomplete information about the identity of the food rewards.

In some cases, the chimpanzees had already seen what item was available in the hidden location and could immediately name it by touching the correct symbol without going to look at the item in the hidden location to see what it was.

In other cases, the chimpanzees could not know what food item was in the hidden location, because either they had not seen any food yet on that trial, or because even if they had seen a food item, it may not have been the one moved to the hidden location.

So, basically the chimps named the food items when they that these were there, and sought them to be sure when they needed more information before naming them.

“This pattern of behavior reflects a controlled information-seeking capacity that serves to support intelligent responding, and it strongly suggests that our closest living relative has metacognitive abilities closely related to those of humans,” the researchers note.

The findings are important not just because it proves yet another important cognitive trait, thought to be solely reserved to humans, is present in non-human primates as well, but because it also may help shed light on the emergence of self-reflective mind during humans’ cognitive evolution. The paper was published in the the journal Psychological Science of the Association for Psychological Science.

Medical research on chimps will no longer be performed

Concluding a debate which lasted for over 7 months, the US Institute of Medicine has released a report that marks a turning point for chimpanzees, our closest relative, in terms of medical research. The panel laid out some stringent rules against all current and future chimp research, installing some dramatic penalties to those who disobey.

This result comes mostly as a result of us understanding that, among others, chimps are capable of so many feelings and thoughts, including grief, happiness, empathy, and they have a basic sense or morality; as a result, subjecting them to any kind of disease, pain or psychological trauma can be qualified unethical by all human standards. It’s a fine line to draw in the sand, and in my opinion, we should have drawn it way before chimps, but it’s a good start nonetheless.

At the same time, from a more cynical yet just as true point of view, this measure was adopted because there simply isn’t as much use for research on chimps than there was before. Researchers are now doing a lot of cell research inside Petri dishes, working on stem cells and so on.

However, they did leave a backdoor open, stipulating that chimps can be used for research when there isn’t a similar model available, and when not doing the research would cause a significant delay or stoppage in important research.

Via 80 beats

Chimp self-awareness

New research shows chimps are self-aware

Until recently it was considered that only humans have the ability of being aware of the fact that they exist as an individual, but studies show that chimps as well as dolphins share this ability.

A recent research revolving around chimps strengthens the idea and shows that our close relatives are indeed self-aware and can anticipate the consequences of their actions upon their environment. The research was published in Proceedings of the Royal Society B and could prove to have a tremendous impact on what’s philosophically considered human and non-human, as well as provide an important first stepping stone for further study of the evolution of consciousness.

Past studies employed various tests to see how self-aware chimps. The most evident and effective of them involved painting a chimp’s face and then facing him against a mirror – if the chimp would have touched his face and try to scrub the paint off than it proves the chimp recognizes himself. A simple self-recognition isn’t evidence enough of self-awareness, though, so researchers sought to test even further.

Takaaki Kaneko and Masaki Tomonaga of the Primate Research Institute in Kyoto designed a series of three experiments to see if chimps, our closest cousins genetically, can reason like humans in certain tasks connected to individuality.

The first test involved three females. The chimps initiated a video game by placing a finger on a touch-sensitive screen and then used a trackball, similar to a computer mouse, to move one of two cursors. The second cursor was implemented to distract the chimps, and was a recording of gestures made earlier by the same animal and set in motion by the computer. As soon as a chimp hit a target or the time lapsed, the test would end. Here’s where the test becomes really interesting to the point of remarkable – each chimp had to point with his finger which of the two cursors he had been manipulating, and received a reward if she chose correctly. All three animals scored above 90 percent. Wow, right ?

“This indicates that the chimpanzees were able to distinguish the cursor actions controlled by themselves from those caused by other factors, even when the physical properties of those actions were almost identical,” the researchers said.

It was still not enough. Researchers couldn’t tell if the chimps showed evidence of self-awareness are they simply have the ability of observing visual cues and clues, so another set of tests were devised.

In the second test both cursors moved independently of efforts to control them, with the trackball being unplugged – one a repeat of movements the chimp had generated in an earlier exercise, and the other a repeat of an “decoy” cursor. If the animals performed well on the first test but poorly on the second, the scientists reasoned, it would suggest that they were not simply responding to visual properties but knew they were in charge.

On the third and final experiment, used only for the chimps who had very high scores, introduced a time delay between trackball and cursor, as if the two were out of sync, and a distortion in the direction the cursor moved on the screen.

Analyzing the results, researchers conclude that “chimpanzees and humans share fundamental cognitive processes underlying the sense of being an independent agent.”

“We provide the first behavioral evidence that chimpanzees can perform distinctions between self and other for external events on the basis of a self-monitoring process.”