Tag Archives: monkey

Female monkeys use male “hired guns” to protect them from predators

Female putty-mosed monkey Credit: C. Kolopp/WCS.

Alarm calls are pretty useful in the animal world. Not only do they help the group (which often includes the alarm caller’s relatives), but they also help the individual making the call, by offering a more privileged position in the group. In the case of putty-nosed monkeys (Cercopithecus nictitans, a type of guenon monkey), males but not females possess loud alarms that serve both as a warning and as predator deterrents.

Researchers with the Wildlife Conservation Society’s (WCS) Congo Program and the Nouabalé-Ndoki Foundation analyzed how these monkeys use these calls not just when reacting to predators, but also to interact with one another. The results suggest that females produce alarm calls mostly to call the males and assemble a defense group. When females assess the nature of the threat and issue anti-predator calls, the females cease their alarm. In other words, the females recruit the males as hired guards.

Males, for their part, advertise the commitment by producing “pyow” calls, which serve as a signature for individual males. Men whose anti-predator calls are more efficient develop a strong reputation as good defenders on their “signature” calls, while those with less reputation are forced to leave the group earlier. Lead author Frederic Gnepa Mehon of WCS’s Congo Program and the Nouabalé-Ndoki Foundation explains:

“Our observations on other forest guenons suggest that if males do not prove to be good group protectors, they likely have to leave groups earlier than good defenders. To date, it remains unclear whether female guenons have a saying in mate choice, but our current results strongly suggest this possibility.”

It’s a cultural thing

The researchers also observed another call among males: a “kek.” Whenever the researchers would present a leopard model, the males would use the “kek” — which is not surprising in itself, but this type of sound has never been reported in previous studies. This suggests the existence of dialects and cultural variations across different populations, a matter fiercely debated in animal research.

Ultimately, it may all boil down to sexual selection, says co-author Claudia Stephan Wildlife Conservation Society’s (WCS) Congo Program and the Nouabalé-Ndoki Foundation:

“Sexual selection might play a far more important role in the evolution of communication systems than previously thought. In a phylogenetic context, what strategies ultimately drove the evolution of communication in females and in males? Might there even be any parallels to female and male monkeys’ different communication strategies in human language?”

The way females manipulate males and convince them to offer protection is remarkable — but as remarkable as these interactions are, researchers suspect there’s still far more we’ve yet to discover. Males have more complex vocal repertoires and could convey even more information with them.

The study has been published in Royal Society Open Science.

To the bitter end: primates can also fall into the sunken cost fallacy

People are notorious for not wanting to waste our time and effort — to the point that we’re willing to sink more of both into an endeavor we’re already on even if it is obviously futile. Our primate relatives seem to be the same.

Image credits Dimitri Houtteman.

Our reluctance to give something up after we’ve worked hard to get it, or otherwise invested a lot of time of effort in, is known as the “sunken cost” fallacy. In essence, the more effort you’ve put into something, the likelier you are to keep working on it even if you know it’s for naught.

It hails from our very distant past, in our ancestors and the ancestors of the human race. It’s a mechanism that makes sure our brains won’t give things up easily and instead wait for a return on investment — giving up too early might mean wasted energy, which could very well mean death in the wild. But there are many scenarios in modern times when the sunken cost fallacy is a net drain on our achievements and quality of life.

New research comes to help us understand the roots of the sunken cost fallacy, finding that two of our related species — capuchin monkeys and rhesus macaques — are also susceptible to this behavior.

Money business

“The epitome of the sunk cost is I’ve invested so much in this, I’m just going to keep going,” said Professor Sarah F. Brosnan from the Georgia State University (GSU), the paper’s senior author.

The team believes there are two factors that work together to generate the sunk-cost fallacy. The first is an evolutionary mechanism meant to help us balance costs and benefits. The second factor is uncertainty regarding the outcome: it might work, so why not keep at it?

They tested this hypothesis through a series of experiments with capuchin monkeys and rhesus macaques, finding that both are susceptible to the sunk cost fallacy, especially so when they’re uncertain about the outcome.

Housed at the GSU’s Language Research Center, the primates have both indoor and outdoor areas available to them, either for play or to take place in voluntary, non-invasive cognitive and behavioral research Brosnan says.

In the study 26 capuchin monkeys and 7 rhesus macaques played a simple video game. Through a joystick, they could move a cursor onto a target. If they successfully hovered it over the target as it moved, they would hear a sound and get a treat. If they failed in the task, they wouldn’t get a reward and the game would restart. After they got the hang of it, the team would test the primates on rounds of either 1, 3 or 7 seconds.

“Monkeys have really quick reaction times on these games,” said Brosnan, “so one second to them is actually a long time.”

Most rounds actually only lasted for 1 second, the team notes. From a purely practical point of view, this means that “if you didn’t get a reward after that, it was actually better to quit and start a new round”, according to Brosnan. That’s not what the animals did, however.

“They persisted 5 to 7 times longer than was optimal, and the longer they had already tried, the more likely they were to complete the entire task.”

Uncertainty was a powerful driver here, as the monkeys were less likely to continue the experiment if they got a signal that additional time and effort was required (though they wouldn’t always stop). They see this as an indication that the sunken cost fallacy is a product of evolution, and it’s deeply rooted in our developmental history (since these species are relatively distantly related to us). An animal’s ability to hunt, forage for food, or to wait for an appropriate social context would benefit from such a mechanism.

It also shows that it’s not a product of our higher mental abilities such as rationalization, from our concern to maintain our public image as someone reliable and capable, or anything similar. These factors likely help flesh the fallacy out, but our relatives can’t boast them to the same extent as we do.

Finally, the team notes that their findings show why tenacity isn’t always a virtue. Understanding the mechanisms that tug on our motivations from the shadows may then help us lead better, more fulfilling lives by focusing on what really matters to us.

“We’re predisposed to keep trying,” Brosnan said. “And when we find ourselves sticking with things, we should also be a little reflective. Do I have a good reason to keep trying? Or should I leave with no reward, because it will save me more in the long run? That’s really hard to do. But hopefully we can use our cognitive abilities to help us overcome the emotional heartache of occasional sunk costs.”

The paper “Capuchin and rhesus monkeys show sunk cost effects in a psychomotor task” has been published in the journal Scientific Reports.

As cities quarantine, animals take to the streets

In Venice, the boats and ferries that used to fill up the canals with hundreds of tourists were now replaced by fishes and even ducks, swimming in clear water. In Japan, hungry deer are taking to the streets; and in Thailand, rival gangs of monkeys are squaring it off in cities.

No, it’s not a Hollywood scenario — nature is starting to reclaim quarantined cities.

Credit Wikipedia Commons

Stay at home. That’s the main message by governments across the world to try to stop the spread of the coronavirus. Many cities, especially in the more affected areas, have been virtually shut off. But, as people withdraw from the outer world, animals are coming in.

All journeys in Venice are now forbidden as part of a set of strict rules of self-confinement, with the only exceptions being walking your dog or buying groceries.

This has led to motorboat taxis, transport and even gondolas emptying the cities’ canals, now taken over by wildlife.

“The water is blue and clear,” hotel manager Gloria Beggiato told The Guardian. “It is calm like a pond, because there are no more waves caused by motorized boats transporting day-tripper tourists. And of course, the giant cruise ships have disappeared.”

Image via Facebook.

Venice isn’t the only city where animals are strolling into town.

In the city of Nara, Japan people reported in their social media seeing hungry deer in the streets and subway stations.

Image credits: okadennis / Twitter.

The deer are reportedly eating potted plants due to a lack of tourists to feed them.

The Nara Park, a popular tourist attraction in Japan, has over 1,000 deer that rarely go outside the 1,240 acres of the park. Until now, that is.

Image credits: okadennis / Twitter.

Visitors to the park usually buy rice crackers to feed the deer. Now, with no tourists, the deer began wandering into the city searching for food. Doing so can be risky for them, experts warned, as they can be hit by cars or eat plastic bags, or even get lost.

Credits: Wikipedia Commons

Meanwhile, in Thailand, two gangs of monkeys are reportedly fighting for supremacy in the city’s mostly-empty plaza. In a video that went viral, the monkey groups started a 10minute fight against each other, leaving the few bystanders shocked.

Here too, the cause might be a shortage of food brought in by declining tourist numbers.

The animals live in the Phra Prang Sam Yot monkey temple but they are dealing with a scarcity of food due to the lack of tourists in the area. That has led them to go into the city and try to get some food.

“The fall in tourist numbers because of Covid-19 may have indeed brought about a shortage of food supply for them,” Asmita Sengupta, an ecologist, told The New York Times. “Feeding the monkeys can have detrimental effects. Once they get used to being fed by humans, they become habituated to humans.”

The effect that the lack of tourists to feed the animals will have on the animals remains to be seen. But experts believe that most of them will likely be fine.

“Most animals living in urban environments already have flexible diets, so chances are good that a lot of these animals are going to be OK,” Christopher Schell, an urban ecologist at the University of Washington, told the NYT.

EDIT: There are multiple stories floating around social media about dolphins in Venice and elephants in tea fields. These are not true and are misleading.

Monkeys are willing to try new solutions to problems, while humans stick to what they know — even if it’s less efficient

We may like to think that we’re smarter, but a new study shows that monkeys show greater cognitive flexibility than humans when deciding how to solve a problem.

Image via Pixabay.

New research at the Georgia State University reveals that capuchin and rhesus macaque monkeys are significantly less susceptible to “cognitive set” bias than humans. In other words, when presented with a new, more efficient option for solving a problem, one of these monkeys shows more willingness to try it out than a human.

Your brain gets smart but your head gets dumb

“We are a unique species and have various ways in which we are exceptionally different from every other creature on the planet,” said Julia Watzek, a graduate student in psychology at Georgia State and the paper’s lead author.

“But we’re also sometimes really dumb.”

Watzek’s study supports earlier findings with other primate species — baboons and chimpanzees — who also showed greater willingness to use shortcuts, when available, to earn a treat. Humans, both the present and previous studies note, have the tendency to persist in using a familiar strategy even if it is more inefficient, and even if they see the alternative at work.

The present study worked with 56 humans, 22 capuchin monkeys, and 7 rhesus monkeys. First, the researchers established a specific strategy to lead to a solution. They taught the participants, both human and animal, through trial and error, to follow a pattern on a computer — this involved pushing a striped square, then a dotted square, and finally a triangle (when it appeared) to receive a reward. Humans were rewarded with either a jingle or points to let them know they got it right, and the monkeys received a banana pellet. Wrong results were penalized with a brief time out and, obviously, no reward.

After all the participants got a strong grasp on the process, the team switched it up. Subsequent trials presented the triangle option immediately, without the first two steps (involving the squares). The team notes that all of the monkeys took the chance and used this ‘shortcut’ — meanwhile, only around 39% of the human participants did. Furthermore, around 70% of the monkeys used the shortcut the very first time it was presented, while only a single human participant did the same.

“There’s a heavy reliance on rote learning and doing it the way you were taught and to specifically not take the shortcut,” Watzek said of the human subjects. “More of the humans do take the shortcut after seeing a video of somebody taking the shortcut, but about 30 percent still don’t,” she adds.

“In another version we told them they shouldn’t be afraid to try something new. More of them did use the shortcut then, but many of them still didn’t.”

Rote learning involves mastery or memorization of a skill or concept through repetition and should be painfully familiar to anyone who’s ever crammed for an exam.

The findings are quite interesting as they show how one of our most powerful tools — learning by repetition — can work to hold us back, lead us to make inefficient decisions, and potentially miss opportunities.

The team notes that, usually, sticking to what you know isn’t that much of a cost; for example, always taking the same route to work isn’t that big of a deal, even if a shorter alternative is available. However, there are cases where relying on inefficient or outdated practices can have dramatic consequences: the team points to the recent global financial crisis when many experts ignored warning signs and persisted with risky trading and lending habits. In the end, it led to a housing market crash and all those delightful economic issues we’ve been dealing with since.

“To set ourselves up for good decision-making, sometimes that means changing available options,” Watzek said. “I’m not proposing to topple the entire Western education system, but it is interesting to think through ways in which we train our children to think a specific way and stay in the box and not outside of it.”

“Just be mindful of it. There are good reasons for why we do what we do, but I think sometimes it can get us into a lot of trouble.”

Sarah Pope, a former graduate student in the Neuroscience Institute at Georgia State and a co-author of the study, also carried out the experiment in Namibia with members of the semi-nomadic Himba tribe (which, the authors note, was not exposed to Western education and live in a less predictable environment). They were quicker to use the shortcut immediately, but more than half still used the three-step process as well. Children aged 7-10 that were given the same task at Zoo Atlanta were four times more likely than adults to use the shortcut — but still, more than half continued to use the learned strategy.

So while our brains are undeniably very efficient tools, we should definitely exercise some oversight; their intentions may be good, but the results don’t always line up.

The paper “Capuchin and rhesus monkeys but not humans show cognitive flexibility in an optional-switch task” has been published in the journal Scientific Reports.

Old World primates can only use two ‘words’ at a time, new research suggests

Old World monkeys can use sentences — but only two words long.

Image via Pixabay.

New research from MIT reports that Old World monkeys can combine two vocalizations into a single sentence. However, they’re unable to freely recombine language elements as we do.


“It’s not the human system,” says Shigeru Miyagawa, an MIT linguist and co-author of a new paper detailing the study’s findings. “The two systems are fundamentally different.”

Along with Esther Clarke, an expert in primate vocalization, who is a member of the Behavior, Ecology, and Evolution Research (BEER) Center at Durham University in the U.K., Miyagawa re-evaluated recordings of Old World monkeys, including baboons, macaques, and the proboscis monkey.

The language of some of these species has been studied in the past, and different species have different kinds of alarm calls for each type of predator. Vervet monkeys have specific calls when they see leopards, eagles, and snakes, for example, because each predator requires different kinds of evasive action. Similarly, tamarin monkeys have one alarm call to warn of aerial predators and one to warn of ground-based predators.

These primates seem able to combine such calls to create a more complex message. The putty-nosed monkey of West Africa has a general alarm call that sounds like “pyow,” and a specific alarm call warning of eagles, “hack.” However, sometimes they will use “pyow-hack” in longer or shorter sequences to warn the group that danger is imminent.

In the paper, Miyagawa and Clarke contend that the monkeys’ ability to combine these terms means they are merely deploying a “dual-compartment frame” which lacks the capacity for greater complexity. The findings, the authors explain, showcase an important difference in cognitive ability between humans and some of our closest relatives.

They explain that these combined calls always start with “pyow”, end with “hack” and that the terms are never alternated. Although the animals do vary the length of the call, the authors say that their language lacks a “combinatorial operation” (the process that allows our brains to arrange individual words into functional sentences). It is only the length of the “pyow-hack” sequence that indicates how far the monkeys will run.

“The putty-nose monkey’s expression is complex, but the important thing is the overall length, which predicts behavior and predicts how far they travel,” Miyagawa says. “They start with ‘pyow’ and end up with ‘hack.’ They never go back to ‘pyow.’ Never.”

Campbell’s monkey, a species in South Africa, uses calls that are reminiscent of a human-style combination of sounds,the team explains that they also use a two-item system and add an “-oo” sound to turn specific sounds into generalized aerial or land alarms.

Miyagawa also notes that when the Old World monkeys speak, they seem to use a part of the brain known as the frontal operculum. Human language is heavily associated with Broca’s area, a part of the brain that seems to support more complex operations. The authors propose that humans’ ability to tap Broca’s area for language may be what enabled speech as we know it today.

“It seems like a huge leap,” Miyagawa says. “But it may have been a tiny [physiological] change that turned into this huge leap.

The paper “Systems Underlying Human and Old World Monkey Communication: One, Two, or Infinite” has been published in the journal Frontiers in Psychology.


Fossil Friday: tiny tooth belonged to the smallest monkey ever found

An 18-million-year-old fossil tooth points towards a tiny primate no heavier than a hamster.


Scan of the fossil tooth.
Image credits Richard F. Kay et al., (2019), JoHE.

The lonesome tooth was found in Peru’s Amazon jungle by a team of Peruvian and American scientists from an exposed river bank along the Río Alto Madre de Dios. A single upper molar, the specimen was just “double the size of the head of a pin” and “could fall through a window screen,” said first author Richard Kay, a professor of evolutionary anthropology at Duke University.

Tiniest monkey

“Primate fossils are as rare as hen’s teeth,” said Kay, who has been doing paleontological research in South America for nearly four decades.

The team found the tooth after sorting through roughly 2,000 pounds of sandstone and gravel collected along the Río Alto Madre de Dios. They report finding hundreds of fossils of rodents, bats, and other animals — but a single monkey tooth. Luckily, it was a molar.

Paleontologists can tell a lot from primate teeth, but molars are particularly telling. Judging from its shape and size, the authors estimate that the animal likely had a diet heavy on fruits and insects, and weighed under half a pound. Some of the larger monkeys in South America today can grow to over 50 times that weight. The team dubbed the animal Parvimico materdei, or “tiny monkey from the Mother of God River.”

“It’s by far the smallest fossil monkey that’s ever been found worldwide,” Kay said.


But, its diminutive size isn’t the only thing that sets this tooth apart. It’s also one of the precious few clues scientists have from a missing chapter in monkey evolution. Primates are believed to have arrived in South America some 40 million years ago from Africa, and quickly diversifying into the 150-plus New World species we know today. The details of how that process unfolded is a bit of a mystery, however, in large part due to a gap in the fossil record (for primates in the area) between 13 and 31 million years ago. Parvimico lies comfortably in that gap.

The new fossil is aged between 17 to 19 million years, “smack dab in the time and place when we would have expected diversification to have occurred in the New World monkeys,” Kay said.

The tooth is now housed in the permanent collections of the Institute of Paleontology at Peru’s National University of Piura. The team is currently on another fossil collecting expedition in the Peruvian Amazon until August, concentrating their efforts in remote river sites with 30-million-year-old sediments. They hope to find more primate fossils.

The paper “Parvimico materdei gen. et sp. nov.: A new platyrrhine from the Early Miocene of the Amazon Basin, Peru” has been published in the Journal of Human Evolution.

Fossil monkey teeth.

Fossil Friday: Newly-found fossil teeth solve ancient monkey mystery

Fossil teeth uncovered in Kenya, Africa, fill a missing link in the evolution of old world monkeys, a new paper reports.

Fossil monkey teeth.

Some specimens of A. metios that the team recovered.
Image credits D. Tab Rasmussen et al., (2019), PNAS.

The 22-million-year-old chompers allowed the team to describe a new species — which they christened Alophia metios — that fills a major gap in the evolution of old world monkeys (family Cercopithecidae), a team of U.S. and Kenyan researchers reports. It forms a link between a 19-million-year old fossil tooth unearthed in Uganda and a 25-million-year-old fossil tooth found in Tanzania.

Surprisingly, the teeth exhibit more primitive features compared to those of earlier species of monkeys, giving us an unique glimpse into what the lineage dined on in its earliest days.

Kenya find me a tooth?

“For a group as highly successful as the monkeys of Africa and Asia, it would seem that scientists would have already figured out their evolutionary history,” said the study’s corresponding author John Kappelman, an anthropology and geology professor at The University of Texas at Austin.

“Although the isolated tooth from Tanzania is important for documenting the earliest occurrence of monkeys, the next 6 million years of the group’s existence are one big blank. This new monkey importantly reveals what happened during the group’s later evolution.”

The team had their sights set specifically on the fossil-rich region of West Turkana, as the time interval they were interested in studying is only represented by a handful of African fossil sites. West Turkana is very arid today, but between 19 and 25 million years ago it was peppered with lush forest and woodland landscapes fed by a network of river and streams. Hundreds of mammal and reptile jaws, limbs, and teeth were recovered during fieldwork, ranging from 21 million to more than 24 million years old — including remains of early elephants.

At first, A. metios’ teeth confused the team. The fossil teeth were very primitive, more primitive than geologically younger monkey fossils, in fact. They even lacked a hallmark structure of monkey teeth, “lophs” — which are a pair of molar crests.

Fossil teeth comparison.

A comparison of cercopithecoid dental evolution over time. Specimens arranged left to right from oldest to youngest species. A are Alophia teeth, B are the same but reversed for comparison. C is Noropithecus, D is Victoriapithecus, E is Nsungewepithecus, F and G Alophia and Alophia reversed, H are Noropithecus teeth in reverse, I are Victoriapithecus teeth in reverse.
Image credits D. Tab Rasmussen et al., (2019), PNAS.

“These teeth are so primitive that when we first showed them to other scientists, they told us, “Oh no, that isn’t a monkey. It’s a pig,” said Ellen Miller, an anthropology professor at Wake Forest University and paper co-author.

“But because of other dental features, we are able to convince them that yes, it is in fact a monkey.”

The species’ name, Alophia, is a tribute to this feature — the word means “without lophs”. It’s quite a significant result, actually, since these lophs are a key feature of monkey teeth today. Lophs and cusps on molars allow the animals to eat a wide range of foods, from animal to plant matter. These teeth are like “uber food processor[s]”, the team explains, and helped monkeys adapt to the diverse environments they inhabit today, from Africa to Asia.

Exactly how and when these structures evolved, however, remained a mystery.  The researchers speculate that Alophia’s primitive dentition was suited to a diet of hard fruits, seeds, and nuts — but not leaves, as these are more efficiently processed by teeth such as those first seen in monkeys from 19 million years ago. This would suggest that the later inclusion of leaves in the diet of monkeys was a key driver of their (and their dental) evolution

“It is usually assumed that the trait responsible for a group’s success evolved when the group originated, but Alophia shows us this is not the case for Old World monkeys,” says co-author Samuel Muteti, a researcher at the National Museums of Kenya.

“Instead, the characteristic dentition of modern monkeys evolved long after the group first appeared.”

Monkeys as a lineage first appeared during a time when Africa and the Arabian peninsula were still joined together. Species here evolved in relative isolation until the whole island-continent connected to Eurasia, between 20 to 24 million years ago. After this time, we see mammals such as antelope, pigs, lions, or rhinos — what we’d consider African species today — making their way to Africa and Arabia.

One of the team’s hypotheses is that these immigrant species placed a lot of environmental stress on monkeys, and competition between them and the new arrivals drove monkeys to start exploiting leaves as a food source. Alternatively, changing climate conditions could have been at the root of this dietary shift.

“The way to test between these hypotheses is to collect more fossils,” Kappelman said. “Establishing when, exactly, the Eurasian fauna entered Afro-Arabia remains one of the most important questions in paleontology, and West Turkana is one of the only places we know of to find that answer.”

The paper “Primitive Old World monkey from the earliest Miocene of Kenya and the evolution of cercopithecoid bilophodonty” has been published in the journal Proceedings of the National Academy of Sciences.

Grooming claws.

Fossils reveal that primates initially had nails and claws, we just lost the latter ones

If you like having nails instead of claws, give a shout-out to society.


Image credits Daniel Nebreda.

Unlike other mammals, us humans and our primate cousins sport nails instead of claws. However, this wasn’t always the case — new fossil evidence shows that ancient primates had specialized grooming claws as well as nails. The findings showcase how primate social structure helped shift claw and nail evolution, the team writes, and overturns our assumption that the earliest primates had nails on all their fingers.

Nailed it

“We had just assumed nails all evolved once from a common ancestor, and in fact, it’s much more complicated than that,” said Jonathan Bloch, study co-author and curator of vertebrate paleontology at the Florida Museum of Natural History.

Grooming goes beyond just looking good. The thick body hair of primates is an ideal habitat for ticks, lice, and a whole host of other creepy crawlies which are both annoying and potential health hazards. As such, the ability to remove these pests formed an evolutionary advantage — and they evolved specialized grooming claws for the purpose. Many primates today retain such claws. Lemurs (subfamily Lemuroidea), lorises (subfamily Lorinae), and galagoes (family Galagidae) have grooming claws on their second toe, while tarsiers (family Tarsiidae) boast them on their second and third toe.

Up to now, we’ve believed that grooming claws developed independently across several primate lineages up to those alive today. However, new fossil evidence suggests that such claws are, rather, a key feature — they date back at least 56 million years, to the oldest-known primates.

Back in 2013, the study’s lead author Doug Boyer found several curious primate fossils at the University of California Museum of Paleontology. These fossils — distal phalanges, the bones that make the tips of fingers or toes — were hidden in sediment samples collected in Wyoming several decades earlier; as often happens, however, they were left waiting in a drawer in the archives. Based on the shape of these fossils, Boyer suspected that their owners sported grooming claws — in general, distal phalanges topped with a claw will be more narrow and tapered, while those supporting a nail will be flat and wide.

Grooming claws.

Lemurs, lorises, and galagoes have nails on most digits and grooming claws on their second toes, as seen on the feet of two greater slow lorises, Nycticebus coucang, in the Florida Museum mammals collection.
Image credits Kristen Grace / Florida Museum.

Bloch’s work involved material recovered from Bighorn Basin, Wyoming. He discovered what initially looked like a “strange, narrow nail” bone, but on later comparison with modern specimens “it looked just like a tarsier grooming claw,” he recounts. Although smaller than a grain of rice, the bone matched the proportions of grooming claws of Teilhardina brandti, a mouse-sized, tree-dwelling primate.

Claw me, claw thee

These were the first hints that the fingers of early primates had grooming claws. To get to the bottom of things, the duo went out to Omomys Quarry, Wyoming, a site once inhabited by an early primate family, Omomys. Here, they found omomyoid grooming claws at three sites spanning 10 million years in the fossil record. The fossils proved beyond a doubt that early primates sported grooming claws.

Why, then, don’t we have some as well?

“The loss of grooming claws is probably a reflection of more complex social networks and increased social grooming,” said Boyer, an associate professor in the department of evolutionary anthropology at Duke University.

“You’re less reliant on yourself.”

This hypothesis could also explain why some species of (more) solitary primates, such as the titi (subfamily Callicebinae) or owl monkeys (family Aotidae) have re-evolved a grooming claw.

But why develop nails in the first place? The team believes it came down to shifts in how primates got around. As climbing, leaping, and grasping took center stage, claws simply became impractical — whereas nails wouldn’t snag or get in the way of anything.

Furthermore, the claws provide new insight into the lives of ancient primates, the team notes, many of which are only known from fossil teeth. Even these tiny claws can offer insight into how our ancestors moved about, their daily behavior, and their social structures.

“We see a bit of ourselves in the hands and feet of living primates,” Bloch said. “How they got this way is a profoundly important part of our evolutionary story.”

The paper “Oldest evidence for grooming claws in euprimates” has been published in the Journal of Human Evolution.

Spider Monkey.

FDA shuts down nicotine addiction study over allegations of “cruel” treatment of animals

The FDA will be sending twenty-six squirrel monkeys to a long-term sanctuary after four deaths in an experiment that didn’t meet the agency’s animal-welfare standards.

Spider Monkey.

Spider Monkeys.
Image credits Angie Toh.

The U.S. Food and Drug Administration (USDA) has shut down an experiment that used squirrel monkeys (genus Ateles) to study nicotine addiction among allegations of animal cruelty. The Washington Post reports that twenty-six monkeys — 20 of which were involved in the study and a further six which were not — will be moved from Arkansas’ National Center for Toxicological Research to an animal sanctuary.

The FDA hasn’t yet announced precisely which sanctuary will receive the primates, although it did note that the process could take a long time.

A smoking gun

The study began in 2014 and aimed to get a better understanding of nicotine addiction. The early stages involved adolescent and adult squirrel monkeys self-administering the substance by pulling on a lever which they, unsurprisingly, did until addiction set in. Then, the team lowered the doses received with each hit, and set out to observe the effects.

In the span of three years (by the summer of 2017), four of these monkeys had died. Three of them succumbed to anesthesia complications when catheters were inserted, and the fourth “was related to [gastric] bloat, the cause of which is often unclear,” according to the agency.

The experiment was brought to the public’s attention last March, after a Freedom of Information Act request was filed for the study’s records by the White Coat Waste Project, a group which opposes taxpayer-funded animal experimentation. They obtained 64 pages of documents pertaining to the study, following their request.

The group’s efforts came to fruition in September, when high-profile primatologist Jane Goodall wrote an open letter to FDA Commissioner Scott Gottlieb. The document called the testing carried out at Arkansas center “shameful,” citing “unnecessary and cruel” practices such as restraining the monkeys and subjecting them to the side effects of nicotine — including vomiting and diarrhea

Gottlieb put the study on hold the same month, and ordered a review be carried out to assess the well-being of the animals involved.

On Friday, he released a statement announcing the end of the study. The commissioner said that while the monkeys were “safe and being well cared for,” the review has raised concerns. Chief among these were a “generalized lack of adequate oversight” and “repeated reported deficiencies” from a third-party animal welfare contractor.

“It is clear the study was not consistent with the agency’s high animal welfare standards,” Gottlieb said, adding that the FDA “will place the monkeys involved in a new permanent sanctuary home, which will provide them with appropriate long-term care.”

With the statement, Gottlieb added that the agency is working on adapting various modeling and technological tools to reduce the need for animal testing. However, some experiments will still require work with animals, including the development of childhood vaccines. With that in mind, the FDA will take further steps to improve its animal program, including the establishment of an Animal Welfare Council to keep watch on all animal research it conducts.

Japanese monkeys are apparently having sexual intercourse with deer

Nature is really messed up sometimes.

Adolescent female Japanese macaque on the back of a male sika deer. Courtesy of Noëlle Gunst

Researchers from the University of Lethbridge in Canada first spotted the behavior earlier this year, but it was a single anecdotal episode. It wasn’t clear why or even exactly what was happening.

“Even the sexual nature of this interaction was not clearly demonstrated,” said Noëlle Gunst.

So she and her colleagues did what you’d expect from scientists: they went back to look for more evidence. They looked at different types of sexual relationships, particularly between adolescent female monkeys and male deer.

“We observed multiple occurrences of free-ranging adolescent female Japanese macaques (Macaca fuscata) performing mounts and sexual solicitations toward sika deer (Cervus nippon) at Minoo, central Japan,” researchers write in the study.

Japanese macaques and sika deer have complex relationships. The macaques sometimes ride deer just like humans ride horses. The deer seem to tolerate it in exchange for grooming and leftover food. But this particular relationship is quite different.

Researchers liken it to homosexual monkey-monkey interactions, where female macaques mount each other. The females also mount the deer, using the same type of movement and the same vocalizations — so the deed appears sexual, at least for the monkeys. The deer, on the other hand, don’t seem as involved.

Some deer shook the macaques off. But others, especially adult male deer, let them do their thing. Some don’t even stop eating while the monkeys are humping them. Still, the acts were persistent and went way beyond mere thrusting or humping. The “monkey-to-deer solicitations … were persistent and conspicuous,” the researchers write. All in all, researchers documented 13 successful pairings and 258 separate mounts. So… what does it all mean?

Interspecies sexual relationships are not unheard of in the animal world, though generally, they’re between closely related species — nothing like this. The purpose of the act can’t possibly be reproductive, so the macaques are doing it for a different reason. Researchers have a few ideas.

The first is that this is a way for adolescent monkeys to start “learning sex” and/or explore their own sexuality. It could also just be a way for them to obtain sexual stimulation with no strings attached — something I’m sure many of us can empathize with. Younger female macaques have also been reported to have intercourse with each other, presumably for the same reasons. Another possibility is that they just don’t have any sexual partners available. Adolescent females are routinely rejected and are not considered desirable among the population.

Lastly, it could also be a non-sexual display. It might be a cultural phenomenon, a social fad. Time will tell, researchers say. They plan on carrying out more observations to detail the nature and purpose of this unusual behavior.

Journal Reference: Noëlle Gunst, Paul L. Vasey, Jean-Baptiste Leca. Deer Mates: A Quantitative Study of Heterospecific Sexual Behaviors Performed by Japanese Macaques Toward Sika Deer.

Rare Amazon monkey spotted for the first time in 80 years

“I was trembling and so excited I could barely take a picture,” said Christina Selby, who snapped the photos.

Kind of looks like one of The Beatles, doesn’t it? Image Courtesy Christina Selby.

It’s been over eight decades since anyone spotted a Vanzolini’s bald-faced saki. The extremely elusive monkey was first spotted in 1936 when Ecuadorian naturalist Alfonso Ollala explored the Amazon, and was thoroughly described by renowned mammalogist Philip Hershkovitz, but has remained enigmatic to this day.

Laura Marsh, the director of the Global Conservation Institute and one of the world’s leading experts on saki monkeys, managed to find five related species — also called flying monkeys — but this particular one remained hidden.

“The target species, Pithecia vanzolinii, are distinctive monkeys like no other primate that might live nearby. They are especially notable for their buffy-colored arms and legs. They were named for Pablo Vanzolini, a famous Brazilian biologist, and musician,” the expedition’s website reads.

Image and text: House Boat Amazon (expedition website).

To find it, Marsh rallied a team of scientists, photographers, conservationists, and local guides. They prepared a four-month expedition in a little-explored part of the Amazon. It was not without peril, as they set out in a two-story houseboat and headed up the Eiru River, near the Brazil-Peru border, but after all, it was all worth it. After just three days, they spotted the first specimen, carelessly flinging itself from branch to branch. This was just the taster.

For the next three months, they mapped the species’ presence in several areas along the Eiru. Armed with this new found knowledge, they hope to convince authorities to take measures to protect the monkey.

“Given what we’ve seen, if no further controls on hunting and forest clearing are put into place outside of what limited reserves currently exist, the saki’s conservation status may become critical,” explained Marsh to Mongabay. “Most of the large monkeys, which are a preferred food source [for local communities], have been hunted out of the forests along the Eiru and Liberdade Rivers.”

The status of the species is yet to be established. Marsh says she will likely recommend “threatened,” but that particular part of the Amazon is drastically changing, mostly due to hunting. People are hunting and fishing at every corner, she says, and this is taking a massive toll. Birds (especially large birds) are rarer and rare, and the status of the saki may be more precarious than anticipated.

Just as we found this species, we may lose it again — this time, to a fault of our own.

“Initially we set out to find this lost species,” she says, but that became a smaller piece of the picture they saw during the expedition.


The findings will be published in the journal Oryx later this month.

Monkey business: A group of monkeys in Indonesia will steal your wallet and sell it back to you — for a cracker

The Monkey Mafia is acting up in Indonesia.

“Hey boss, you got something good for me?” Image credits: McKay Savage.

Researchers have identified and described a nasty but fascinating behavior of monkeys. By themselves, they’ve learned to steal the valuables of tourists and then sell it back for a profit.

The long-tailed macaques (Macaca fascicularis) living near the Uluwatu temple in Indonesia are not picky — they’ll steal anything: wallets, cash, hats, cameras, anything that looks like it’s valuable. Then, they’ll run off to the temple staff to sell their ill-gotten goods for a tasty treat. This behavior has been discussed anecdotally for years, but it hasn’t been properly studied. So Fany Brotcorne, a primatologist at the University of Liège in Belgium, set out to see how the macaques act, and what drove them to act this way.

“It’s a unique behaviour. The Uluwatu Temple is the only place in Bali where it’s found,” she says, which suggests it is a learned behaviour rather than an innate ability.

She spent four months around the temple, documenting the monkeys’ behavior — which I can only imagine was a unique experience in itself.

She learned that it’s a learned behavior because when a new group of macaques moved to the area, they too observed the other monkeys and soon copied the behavior. There were other clues as well. Aside from monkeys learning from one another, young males (who are more prone to taking risks) were observed to exhibit this behavior more than others. Basically, this appears to be a cultural behavior, transmitted from generation to generation and from monkey to monkey. In other words, it’s more like a human behavior than an animal behavior.

“This indicates that it can indeed be a new behavioural tradition in primates and one that teaches us that new traditions can involve robbing and bartering with a different species,” he says.

In fact, Brotcorne believes that this could actually help us understand a thing or two about ourselves and how our own cognitive abilities developed.

“Bartering and trading skills are not well known in animals. They are usually defined as exclusive to humans,” she says.

Amusingly, she also said that she herself fell victim to the monkeys — not once, but several times.

“Oh, so many times,” she says. “The monkeys were always trying to steal my hat, my pen, even my research data!”

It’s not the first time monkeys exhibit a surprising behavior. In a separate experiment, researchers taught monkeys the concept of money. Not long after, the first prostitute monkey appeared.

Journal Reference: Fany Brotcorne, Gwennan Giraud, Noëlle Gunst, Agustín Fuentes, I. Nengah Wandia, Roseline C. Beudels-Jamar, Pascal Poncin, Marie-Claude Huynen, Jean-Baptiste Leca — Intergroup variation in robbing and bartering by long-tailed macaques at Uluwatu Temple (Bali, Indonesia). DOI: 10.1007/s10329-017-0611-1

Japanese macaque. Credit: Wikimedia Commons

Monkeys have the vocal hardware required for speech but lack the brains

Japanese macaque. Credit: Wikimedia Commons

Japanese macaque. Credit: Wikimedia Commons

Macaques and likely other monkeys, as well as apes, are technically capable of vocalizing vowel sounds and even whole sentences, not much different from how humans do it. This was revealed by a new study which found no anatomical limitations to keep monkeys from being able to speak. However, macaques lack the neuro-cognitive machinery to generate speech. It’s an important distinction that will be of great use in our quest to unravel the origin of speech.

The uniqueness of human vocalized communication is difficult to pin down. For one, speech requires a precise coordination of the vocal anatomy, which includes the tongue, lips, and larynx. This is only half the picture, though, because having a vocal range is not enough. You also require dedicated brain regions that are meant for processing speech.

It was never clear if our evolutionary edge is due to vocal anatomy, brain wiring, or a combination of both. An international team of researchers has now simplified the picture by effectively singling out one of these assumptions.

“Now nobody can say that it’s something about the vocal anatomy that keeps monkeys from being able to speak—it has to be something in the brain. Even if this finding only applies to , it would still debunk the idea that it’s the anatomy that limits speech in nonhumans,” said Asif Ghazanfar, a Princeton University professor of psychology and the Princeton Neuroscience Institute, and of the study’s co-authors.

“Now, the interesting question is, what is it in the human brain that makes it special?”

Ghazanfar and colleagues used sophisticated imaging technology based on X-rays to trace all the subtle movements of the macaque’s vocal anatomy. The recorded footage was then turned into a model by researchers from the VUB Artificial Intelligence Laboratory in Belgium which could simulate a macaque’s vocal range based on the physical attributes recorded by X-ray.

X-rays were used to trace the movements of the different parts of a macaque's vocal anatomy. Asif Ghazanfar, Princeton Neuroscience Institute.

X-rays were used to trace the movements of the different parts of a macaque’s vocal anatomy. Asif Ghazanfar, Princeton Neuroscience Institute.

We are able to carry out meaningful conversations because of words. Words start off with a source sound produced by the vocal box, which is then altered by the lips or tongue. For instance, the words “bat” and “bot” have the same vocal source. Its frequencies, however, are then altered by the movements of the mouth and tongue.

When a macaque’s grunt or source sound was plugged into the computer model, the researchers found comprehensible vowel sounds can be formed. Were the monkey able to direct its vocal anatomy, it could utter complete sentences. But it would not sound similar to a human, the researchers warn in the paper published in Science Advances.

“This new result tells us that there’s still a big mystery concerning where human speech came from,” said Laurie Santos, a psychology professor at Yale University who is familiar with the research but had no role in it.

Though the study has only be made included macaques, it’s likely the findings apply to other primate species. Being older in the evolutionary tree than apes, it’s also likely that species like gorillas or chimps also share the same vocal capabilities. “I think that means we’re in for some exciting new answers soon,” Santos said.

What will likely happen next is a more in-depth look into monkey and app brains to see what they’re missing that makes them unable to speak. More sophisticated models might also help us unravel the origin of speech in humans.

“Their value as a model system for studying the parts of the brain that directly control the biomechanics of orofacial movements during speech and other vocal behaviors will increase,” Ghazanfar said. “Moreover, it’s going to force us to think more carefully about how speech evolved, how our brain is uniquely human and how we can use these model animals in the future to understand what goes wrong when we are unable to speak.”

Chinese researchers create autistic monkeys

Researchers in China have genetically engineered autistic monkeys which exhibit almost no social interaction. Now, they say they’ll try to cure it.

Macaque monkeys with human DNA display an autism-like disorder.
Image via MIT.

Autism is an umbrella term for conditions characterized by impaired social interaction and restricted and repetitive behavior. Controversy still surrounds autism, especially regarding the cause and mechanisms through which it manifests itself. Treatment is also a matter of debate, and is generally very expensive and often only partially successful.  For someone born in 2000, a US study estimated an average lifetime cost of $4.07 million, with most biggest chunk being accounted by lost economic productivity. With that in mind, a team of medics believe they can better understand the condition by treating it on monkeys.

Neuroscientist Zilong Qiu of the Shanghai Institutes for Biological Sciences says his team has generated more than a dozen monkeys with a genetic error that causes them to exhibit autistic behavior. The same genetic error is associated with mental retardation and autistic features in humans.

“The monkeys show very similar behavior [to] human autism patients,” Qiu said during a conference call organized by Nature, the journal that published the report today. “We think it provides a very unique model.”

The monkeys are more easily stressed, they avoid eye contact and become nervous when eye contact is made and “grunt, coo, and scream” more often if challenged in this way, according to Qiu’s team – echoing the behaviors reported in humans.

Decades of studies on autism in mice have yielded very few leads and Qiu believes monkey studies could be the much needed clue. He says scientists would now be able to study what brain networks had been disrupted and try out treatments to see what works. They are also considering  new genome-editing technologies, such as CRISPR, he says.

However, their plan has been met with skepticism by some other researchers.

“I think we need to be cautious calling this a model … it does not quite accomplish that,” says Huda Zoghbi, whose lab at the Baylor College of Medicine discovered in 1999 that damage to the MECP2 gene causes Rett syndrome, a form of autism affecting girls.

She went on to add that despite some symptoms being similar to those in humans, they are not identical, and some of the most important symptoms (like seizures) are absent.

“For the sake of the field and the families it is important that we study models that are constructed to genetically mimic what happens in humans and that reproduce features of the syndrome as closely as possible,” Zoghbi says. “It is important that we hold [these] standards to nonhuman primate models.”

The risk is that not only will these models not mimic the right scenario, but they could give us false information, giving misleading clues about two non-identical situations. John Spiro, deputy scientific director of the Simons Foundation Autism Research Initiative in New York, believes researchers will remain divided on this issue.

“There is a sentiment that you are never going to generate enough animals to be able to do the really important experiments,” he says. “But a lot of people feel extraordinary strongly that rodents aren’t good enough. I would say the smartest minds in the field say we have got to do this.”

I also feel that a matter of ethics should also be discussed here. Engineering autistic monkeys definitely sounds like a debatable idea.

The brain scan of the monkey skull

An ancient monkey skull hints to how primate brains might have evolved

Duke University researchers made micro CT scans of the skull of ancient monkey and found its brain, though tiny by modern standards, was far more complex than previously thought. The fossils, discovered in Kenya in 1997, belong to a monkey ancestor who lived some 15 million years ago.

The brain scan of the monkey skull

The 3d skull scan of the Victoriapithecus skull. Fred Spoor/Max Planck Institute for Evolutionary Anthropology

The researchers were quite struck by what they found. First, they calculated the brain volume of the ancient monkey, called Victoriapithecus. It was  36 cubic centimeters or roughly twice as small as modern monkeys. Despite the fact that its brain is small in relation to the monkey’s body size, it was incredibly complex. In some aspects, it was actually far more complex than those of modern relatives belonging to the Old World monkeys, a group that includes baboons and macaques. For instance, the olfactory bulb – the brain region responsible for analyzing smell – was three times larger than expected.

“In living higher primates you find the opposite: the brain is very big, and the olfactory bulb is very small, presumably because as their vision got better their sense of smell got worse,” said Lauren Gonzales, lead author of the paper published in Nature.


Image: Wikimedia Commons

Previously, the community thought that in the primate family, which includes both apes and humans, the brains first got bigger and the began to fold and turn into more complex areas. In monkeys, at least, this evolutionary chain of events seems to be reversed – first the brains became more complex and only then got larger. The same might be true for us primates, eventually.

The Victoriapithecus skull is very old. It’s in fact the oldest Old World monkey fossil we’ve found yet. Without hard fossil evidence, scientists have long gone back and forth over which came first—large brain size or increased brain complexity.

A rhesus monkey preparing to choose the four and five combination on the panel. (c) PNAS

Monkeys can do math, study proves


Photo: PNAS

It’s long been supposed that monkeys are capable of mental arithmetics, but it was only recently that this was proven for a fact by neuroscientists at the Margaret Livingstone of Harvard Medical School in Boston. The researchers taught three rhesus macaques to identify symbols representing the numbers zero to 25, then when given the choice between two panels, one depicting a number symbol and the other depicting an addition of two other symbols, the monkeys proved they could do math and choose which of the two was bigger. This doesn’t just mean that monkeys are smarter than everyone might have thought; it also raises important questions as to how mammalians brains, including those of us humans, work and engage with our surroundings.

Previously, researchers showed that chimpanzees could add single-digit numbers. The results were nothing short of remarkable, but the study didn’t conclude what process go on in the primate’s brain when this addition was going on. The new study which studied the rhesus monkeys sheds more light on these aspects.

Margaret Livingstone of Harvard Medical School in Boston and colleagues trained three monkeys to associate the Arabic numbers 0 through 9 and 15 select letters with the values zero through 25. To receive food, the monkey had to choose between two boards: one that showed an addition of two symbols and the other only one symbol. If the monkey chose the greater number of the two, it received more tasty food.  Within 4 months, the monkeys had learned how the task worked and were able to effectively add two symbols and compare the sum to a third, single symbol.

So be certain the monkeys were simply memorizing the symbols and all possible combinations (that’s no how arithmetic works, clearly), the researchers introduced an entirely different set of symbols representing the numbers zero to 25 in the form of tetris-like blocks instead of the familiar Arabic numbers and Latin letters. According to the study, all three monkeys were on average capable of choosing the correct answer “well above” 50 percent of the time, which is statistically relevant enough to infer that the rhesus monkeys could actually do the math and not simply rely on chance.

A rhesus monkey preparing to choose the four and five combination on the panel. (c) PNAS

A rhesus monkey preparing to choose the four and five combination on the panel. (c) PNAS

What’s interesting to note is that after the researchers analyzed their findings in greater deal they began to understand why the monkeys weren’t right most of the time with their calculations. Apparently, they tended to underestimate a sum compared with a single symbol when the two were close in value—sometimes choosing, for example, a 13 over the sum of eight and six. Basically, when the monkey was adding two numbers, it paid close attention to the large of the two and then added only a fraction of the lesser number to make up the sum; which obviously came out wrong from the real answer.

This peculiar, since one prevailing theory on how the brain processes number representations is that it underestimates the value of larger numbers in a systematic and unchangeable way. The present findings contradict this idea and may help researchers better understand how human beings process numbers. Also, the findings could also help shed light on dyscalculia (similar to dyslexia, only it involves failing to perform mathematical operations instead of reading – an interesting piece about it worth reading here). It’s not that people with dyscalculia have an intellect comparable with rhesus monkeys – far from it, apart from their disability to perform arithmetic, they’re totally cognitively functioning human beings. Estimating values, the present study suggests, may be key to how addition works.

Results were published in the journal PNAS.

25 million year old primate fossil found

Paleontologists working at Ohio University have unearthed evidence of two new species of ancient primates, named Rukwapithecus fleaglei and Nsungwepithecus gunnellifa, which offer solid evidence of a split between Old World monkeys and apes.

Artist’s impression of the newly discovered Rukwapithecus, front, and Nsungwepithecus, right (Mauricio Anton).

Artist’s impression of the newly discovered Rukwapithecus, front, and Nsungwepithecus, right (Mauricio Anton).

Geological and paleontological analysis have shown that the fossils are approximately 25 million years old, which puts them in the late Oligocene. The Oligocene is a very important period in terms of fauna, lots of important and significant species emerge at that time. It’s also a crucial period for primates, who begin to differentiate and expand.

Why are these fossils relevant, and very important? Well, they are much older than previously documented for either of two major groups of primates: the group that today includes apes and humans (hominoids), and the group that includes Old World monkeys such as baboons and macaques (cercopithecoids). We really don’t know that much about the origins of early anthropoid splits. Anthropoids include Platyrrhines (New world Monkeys) and Catarrhines: us, the other great apes, lesser apes (gibbons), and Old World Monkeys (think baboons). Why don’t we know that much about them? Because we didn’t really find that many fossils which could shed some light on the issue.

“The late Oligocene is among the least sampled intervals in primate evolutionary history, and the Rukwa field area provides a first glimpse of the animals that were alive at that time from Africa south of the equator,” said Prof Nancy Stevens, lead author of a paper reporting the discovery in the journal Nature.

Specimen of Rukwapithecus fleaglei, a partial right mandible bearing the lower fourth premolar, first and second molars, and partially erupted third molar (Patrick O’Connor / Ohio University).

Specimen of Rukwapithecus fleaglei, a partial right mandible bearing the lower fourth premolar, first and second molars, and partially erupted third molar (Patrick O’Connor / Ohio University).

The fossils they found were a mandible preserving several teeth for Rukwapithecus fleaglei and a tooth and jaw fragment for Nsungwepithecus gunnelli. It may not seem like much, but the morphology of the mandible is a very good standard to determine species. The size and shape of the teeth, as well as the type of the bone can also give lots of indications about the size of the animal, what it ate, etc.

The study documents for the first time that the two lineages were already evolving separately during this geological period. Previous finds put this split a few million years later.

“The new discoveries are particularly important for helping to reconcile a long-standing disagreement between divergence time estimates derived from analyses of DNA sequences from living primates and those suggested by the primate fossil record,” Prof Stevens said.

“Studies of clock-like mutations in primate DNA have indicated that the split between apes and Old World monkeys occurred between 30 million and 25 million years ago. Fossils from the Rukwa Rift Basin in southwestern Tanzania provide the first real test of the hypothesis that these groups diverged so early, by revealing a novel glimpse into this late Oligocene terrestrial ecosystem.”

Via Sci News.

Lesula Monkey Congo

New beautifully colored monkey species discovered in Africa

Lesula Monkey CongoThis bright little fellow is known as the lesula to the local people of a remote part of the Democratic Republic of Congo, and as of recently has been recognized as a new, distinct species of monkey. Lucky for the lesula, the discovery came in the nick of time for preservation efforts to be rolled, as the species faces extinction due to extensive hunting.

Though the monkey bares a cunning resemblance to the owl-faced monkey, the lesula can be easily differentiated by its blond chin and upper chest, in contrast to its dark limbs. Also It has a reddish-colored lower back and tail. The first lesula found was a young captive animal seen in 2007 in a school director’s compound in the town of Opala in the Democratic Republic of Congo.

“And adult males have a huge bare patch of skin in the buttocks, testicles and perianal area,” said John A. Hart, the researcher who described the coloring. “It’s a brilliant blue, really pretty spectacular.”

Look closely in the lesula’s eyes – doesn’t it remind you of a person, a known figure of some kind? Well, some readers from CNN quickly jumped on the news and started making bets on who bares the greatest resemblance to the lesula. Finalists include David Schwimmer from Friends, Jake Gyllenhaal, da Vinci’s Mona Lisa or Jesus.

Lesula Monkey Congo

Laughs aside, since it was first sighted, thorough tests and analysis were performed which revealed that indeed that the monkey is a genetically distinct species, now called Cercopithecus lomamiensis by its scientific name. Researchers are worried, however, concerning the lesula’s fate as the new monkey’s range covers one of Congo’s last “biologically unexplored” forest blocks. Although the scientists involved in the study were able to identify more lesulas in the wild, “under the current trends of uncontrolled bush-meat hunting, it could become very endangered.”

“After searching for several days in the most densely populated lesula habitat, I finally got a glimpse of the species on the last day in the forest,”  said Florida Atlantic University (FAU) Assistant Professor of Anthropology Kate Detwiler. “After the excitement of confirming the new species in the genetics lab, the chance to see the lesula in its natural habitat was especially gratifying. The fact that we are just finding a new species of primate in this area of the Congolese rain forest in the 21st century indicates that there is still so much to learn. We are very lucky that we found the lesula while there is still time to save it, and the discovery fuels the drive to raise awareness about and support for conservation of this incredibly diverse ecosystem.”

Indeed, as Professor Detwiler perfectly synthesizes, we’re in 21st century and still there are species, of monkeys even, which have yet to be identified. FAU’s news statement said that a significant area of the new species’ known range is now proposed as a new protected area, the Lomami National Park.  ”This will be the first national park established in the Congo through consultation with local communities from the outset,” the statement added.

The findings were described in a paper published in the journal Plos ONE.

Wild monkeys to monitor radiation levels in Japan

How do you measure the radiation level at the Fukushima power plant, without endangering people in the process? Researchers found quite a creative way of doing this: they tagged wild monkeys which hang around the place anyway with radiation sensors.

Takayuki Takahashi explained that he and his team are planning to put radiation-measuring collars on three such monkeys, as well as GPS devices that also measure the distance from the ground. The information will help scientists understand how grave the radiation is and how it may affect the environment (humans, plants and animals).

This idea is extremely creative and interesting especially because monkeys walk on the ground and climb trees as well, and can measure radiation at ground level and higher above it. The next step in the work is to also employ the help of wild boars, which have the advantage of moving around quite a lot and being very resistant.

Via 80 beats

Monkeys have regrets too

Much like humans, monkeys too exhibit signs of regret, and they wonder themselves what might have been, according to a recent study published by researchers from Yale.

The study, published in the Neuron journal, suggests that aside from regrets, monkeys often wonder about how different actions would lead to different outcomes; as researchers state, aside from being extremely interesting in itself, this could also shed some light on some of the most basic human psychological traits.

The general belief is that animals learn only on their previous experiences, mostly on a trial and error basis. But Daeyeol Lee, a professor of neurobiology at the Yale School of Medicine said he has long believed that this was inaccurate, and set out to prove his hunch; he succeeded.

“When people have regret, they’re thinking about what could have happened; it’s about imagining what could have happened,” said Lee, co-author of the study. “The reason you do this is because it actually broadens the potential for learning tremendously. It seems like such a fundamental question that I would be surprised if it were exclusive to humans.”

To test their theory, researchers set out and taught the monkeys to play a computer simulation of ‘rock, paper, scissors’, while monitoring their brain’s activity. If they won, they would get a large reward, if they tied, a small reward, and they got nothing when they lost. Most of the monkeys, they observed, would pick whichever symbol they would have won with in the previous game. In other words, Lee said, they were able to think abstractly and imagine an alternative outcome.

With the help of brain imaging material, the Yale researchers were able to pinpoint the activity in the brain triggered by this kind of thinking, and the different forms that it takes. According to them, regret takes place in two different forms, both of which take place in parts of the prefrontal cortex. Most regret is also good, and helps you learn and evolve.

“Your brain is running this mental simulation about how you could do things differently in the future to get a better outcome.”

But when people obsess about their regrets, this often leads to depression.

“It’s an important first step,” he said. “If someone has a pathological amount of regret, and you want to ameliorate it some way, you can target those areas. And when you’re testing those drugs, then you know where to look.”