Grey-haired chimpanzees are not always old


This 2018 BBC video says about itself:

Chimpanzees show empathy and altruism just like humans do – we can even learn from how they behave, explains anthropologist Frans de Waal.

From George Washington University in the USA:

For chimpanzees, salt and pepper hair not a marker of old age

New GW study finds there is significant variation in how chimpanzees experience pigment loss

July 14, 2020

Silver strands and graying hair is a sign of aging in humans, but things aren’t so simple for our closest ape relatives — the chimpanzee. A new study published today in the journal PLOS ONE by researchers at the George Washington University found graying hair is not indicative of a chimpanzee’s age.

This research calls into question the significance of the graying phenotype in wild non-human species. While graying is among the most salient traits a chimpanzee has — the world’s most famous chimpanzee was named David Greybeard — there is significant pigmentation variation among individuals. Graying occurs until a chimpanzee reaches midlife and then plateaus as they continue to age, according to Elizabeth Tapanes, a Ph.D. candidate in the GW Department of Anthropology and lead author of the study.

“With humans, the pattern is pretty linear, and it’s progressive. You gray more as you age. With chimps that’s really not the pattern we found at all,” Tapanes said. “Chimps reach this point where they’re just a little salt and peppery, but they’re never fully gray so you can’t use it as a marker to age them.”

The researchers gathered photos of two subspecies of wild and captive chimpanzees from their collaborators in the field to test this observation. They visually examined photos of the primates, evaluated how much visible gray hair they had and rated them accordingly. The researchers then analyzed that data, comparing it to the age of the individual chimpanzees at the time the photos were taken.

The researchers hypothesize there could be several reasons why chimpanzees did not evolve graying hair patterns similar to humans. Their signature dark pigmentation might be critical for thermoregulation or helping individuals identify one another.

Dr. Brenda Bradley, an associate professor of anthropology, is the senior author on the paper. This research dates back to an observation Dr. Bradley made while visiting a field site in Uganda five years ago. As she was learning the names of various wild chimpanzees, she found herself making assumptions about how old they were based on their pigmentation. On-site researchers told her that chimps did not go gray the same way humans do. Dr. Bradley was curious to learn if that observation could be quantified.

There has been little previous research on pigmentation loss in chimpanzees or any wild mammals, Dr. Bradley said. Most existing research on human graying is oriented around the cosmetic industry and clinical dermatology.

“There’s a lot of work done on trying to understand physiology and maybe how to override it,” Dr. Bradley said. “But very little work done on an evolutionary framework for why is this something that seems to be so prevalent in humans.”

The researchers plan to build on their findings by looking at the pattern of gene expression in individual chimpanzee hairs. This will help determine whether changes are taking place at the genetic level that match changes the eye can see.

This study comes ahead of World Chimpanzee Day on July 14. GW’s faculty and student researchers make contributions to our global understanding of chimpanzees and primates as part of the GW Center for the Advanced Study of Human Paleobiology. Through various labs, investigators study the evolution of social behavior in the chimpanzees and bonobos, the evolution of primate brain structure, and lead on-the-ground projects at the Gombe Stream Research Center in Tanzania. Dr. Bradley’s lab is also currently working on research about color vision and hair variation in lemurs.

Chimpanzee and bonobo cooperation, new research


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

From the Max Planck Institute for Evolutionary Anthropology in Germany:

In the wild, chimpanzees are more motivated to cooperate than bonobos

When informing about a threat territorial chimpanzees are more motivated to cooperate than less territorial bonobos

June 24, 2020

Summary: Scientists investigated cooperation dynamics in wild chimpanzees (Tai, Ivory Coast) and bonobos (LuiKotale, DCR) using a snake model. While chimpanzees cooperate to defend their territory, bonobos do not. The study reveals no differences in both species’ social intelligence but supports theories linking territoriality and in-group cooperation in humans since chimpanzees were more motivated to cooperate by informing others of a threat as compared to bonobos.

We humans have unique cooperative systems allowing us to cooperate in large numbers. Furthermore, we provide help to others, even outside the family unit. How we developed these cooperative abilities and helping behaviour during our evolutionary past remains highly debated. According to one prominent theory, the interdependence hypothesis, the cognitive skills underlying unique human cooperative abilities evolved when several individuals needed to coordinate their actions to achieve a common goal, for example when hunting large prey or during conflict with other groups. This hypothesis also predicts that humans who rely more on each other to achieve such goals, will be more likely to provide help and support to one another in other situations.

“While we cannot study the behaviour of our human ancestors,” explains Roman Wittig, a senior author and head of the Taï Chimpanzee Project, “we can learn how relying on others may influence helping behaviour in our ancestors by studying our closest living relatives, chimpanzees and bonobos.” Chimpanzees are more territorial than bonobos and in some populations engage more frequently in group hunts. According to the interdependence hypothesis, chimpanzees should thus have evolved a higher tendency to cooperate and help others in the group.

To test this hypothesis, researchers from the Max Planck Institute for Evolutionary Anthropology, Harvard University and Liverpool John Moores University, presented 82 chimpanzees and bonobos from five different communities with a model of a Gaboon viper, a deadly snake. During the experiment, the apes could cooperate with each other by producing alarm calls to inform conspecifics about the snake. This represents the first experimental study ever conducted in wild bonobos. “This experimental study is a novel and promising approach to probe bonobo’s mind,” says Gottfried Hohmann, a senior author on the study and head of the LuiKotale bonobo project. Martin Surbeck, co-author on the paper adds: “This study should stimulate several more experimental studies on wild bonobo cooperation, cognition, and communication.”

In this study, researchers show that both chimpanzees and bonobos can assess what others know, as they stopped calling when all individuals around had seen the snake. However, chimpanzees warned each other more efficiently: individuals arriving later at the snake were less surprised upon seeing it than late arriving bonobos. This suggests chimpanzees were better informed of the snake’s presence than bonobos. Indeed, late-arriving chimpanzees were more likely to hear a call before reaching the snake than bonobos in the same circumstance, suggesting that the motivation to help and warn others was higher in chimpanzees.

“Our findings support the theory that the extreme reliance on each other in humans, for instance during war and group hunting, may have promoted the evolution of some forms of help and support to others, even sometimes to complete strangers,” says first author Cédric Girard-Buttoz. The authors confirm that chimpanzees may have some awareness of others’ knowledge and demonstrate for the first time this ability in wild bonobos.

“How chimpanzees and bonobos apparently keep track of other’s knowledge, the specific cognitive skills to do this, are not clear,” adds Catherine Crockford, last author of the study, “we face a major challenge to understand which cognitive skills are unique to humans and which are shared with other apes.”

What mammals and birds believe


This February 2020 video says about itself:

Scrub jays are basically the west coast equivalent of blue jays in the United States (except one species does occur on the east coast…). There are multiple species of scrub jays and their relatives, and they may be found in Central America, as well.

Scrub jays are about the same size as blue jays and they love to eat acorns! Sometimes young scrub jays will stick around with their parents and help raise their siblings – other times they just leave as soon as they’re able. Join us on this episode of Animal Fact Files to learn more about these bright blue birdies.

From the Ruhr-University Bochum in Germany:

What it means when animals have beliefs

Chimpanzees, some dog species and even scrub jay and crows have beliefs.

June 17, 2020

Humans are not the only ones who have beliefs; animals do too, although it is more difficult to prove them than with humans. Dr. Tobias Starzak and Professor Albert Newen from the Institute of Philosophy II at Ruhr-Universität Bochum have proposed four criteria to understand and empirically investigate animal beliefs in the journal Mind and Language. The article was published online on 16 June 2020.

Flexible use of information about the world

The first criterion for the existence of beliefs worked out by the philosophers is that an animal must have information about the world. However, this must not simply lead to an automatic reaction, like a frog instinctively snapping at a passing insect.

Instead, the animal must be able to use the information to behave in a flexible manner. “This is the case when one and the same piece of information can be combined with different motivations to produce different behaviours,” explains Albert Newen. “For example, if the animal can use the information that there is food available at that moment for the purpose of eating or hiding the food.”

Information can be relinked

The third criterion says that the information is internally structured in a belief; accordingly, individual aspects of that information can be processed separately. This has emerged, for example, in experiments with rats that can learn that a certain kind of food can be found at a certain time in a certain place. Their knowledge has a what-when-where structure.

Fourthly, animals with beliefs must be able to recombine the information components in novel ways. This reassembled belief should then lead to flexible behaviour. Rats can do this too, as the US researcher Jonathan Crystal demonstrated in experiments in an eight-armed labyrinth. The animals learned that if they received normal food in arm three of the maze in the morning, chocolate could be found in arm seven at noon.

Crows and scrub jays meet all criteria

The authors from Bochum also cite crows and scrub jays as examples of animals with beliefs. British researcher Nicola Clayton carried out conclusive experiments with scrub jays. When the birds are hungry, they initially tend to eat the food. When they are not hungry, they systematically hide the leftovers. In the process, they encode which food — worm or peanut — they have hidden where and when. If they are hungry in the following hours, they first look for the worms they prefer. After the period of time has elapsed that takes worms to become inedible, they head for the peanut hiding places instead.

“What best explains this change in behaviour is the birds’ belief about the worms being spoiled and their beliefs about the location of other food items,” says Tobias Starzak. The animals also react flexibly in other situations, for example if they notice that they are being watched by rivals while hiding; if this is the case, they hide the food again later.

Flexible behaviour, which can be interpreted as caused by beliefs, has also been shown in rats, chimpanzees and border collies. “But probably many more species have beliefs,” supposes Albert Newen.

Chimpanzee and human speech, new research


This 9 May 2014 video from England says about itself:

How to Speak Chimpanzee | Extraordinary Animals | BBC Earth

Dr Katja Liebal is at Twycross Zoo in Leicestershire to study the chimps in their enclosure. She believes that the chimps have their own complex system of communication and hopes to compile the world’s first chimpanzee dictionary.

From the University of Warwick in England:

Chimpanzees help trace the evolution of human speech back to ancient ancestors

May 27, 2020

One of the most promising theories for the evolution of human speech has finally received support from chimpanzee communication, in a study conducted by a group of researchers led by the University of Warwick.

The evolution of speech is one of the longest-standing puzzles of evolution. However, inklings of a possible solution started emerging some years ago when monkey signals involving a quick succession of mouth open-close cycles were shown to exhibit the same pace of human spoken language.

In the paper ‘Chimpanzee lip-smacks confirm primate continuity for speech-rhythm evolution’, published today, the 27th May, in the journal Biology Letters, a consortium of researchers, including St Andrews University and the University of York, led by the University of Warwick, have found that the rhythm of chimpanzee lip-smacks also exhibit a speech-like signature — a critical step towards a possible solution to the puzzle of speech evolution.

Just like each and every language in the world, monkey lip-smacks have previously shown a rhythm of about 5 cycles/second (i.e. 5Hz). This exact rhythm had been identified in other primate species, including gibbon song and orangutan consonant-like and vowel-like calls.

However, there was no evidence from African apes, such as gorillas, bonobos and chimpanzees — who are closer related to humans, meaning the plausibility of this theory remained on hold.

Now, the team of researchers using data from 4 chimpanzee populations have confirmed that they too produce mouth signals at a speech-like rhythm. The findings show there has been most likely a continuous path in the evolution of primate mouth signals with a 5Hz rhythm. Proving that evolution recycled primate mouth signals into the vocal system that one day was to become speech.

African great apes, the closest species to humans, had never been studied for the rhythm of their communication signals. Researchers investigated the rhythm of chimpanzee lip-smacks, produce by individuals while they groom another and found that chimpanzees produce lip-smacks at an average speech-like rhythm of 4.15 Hz.

Researchers used data across two captive and two wild populations, using video recordings collected at Edinburgh Zoo and Leipzig Zoo, and recordings of wild communities including the Kanyawara and the Waibira community, both in Uganda.

Dr Adriano Lameira, from the Department of Psychology at the University of Warwick comments:

“Our results prove that spoken language was pulled together within our ancestral lineage using “ingredients” that were already available and in use by other primates and hominids. This dispels much of the scientific enigma that language evolution has represented so far. We can also be reassured that our ignorance has been partly a consequence of our huge underestimation of the vocal and cognitive capacities of our great ape cousins.

“We found pronounced differences in rhythm between chimpanzee populations, suggesting that these are not the automatic and stereotypical signals so often attributed to our ape cousins. Instead, just like in humans, we should start seriously considering that individual differences, social conventions and environmental factors may play a role in how chimpanzees engage “in conversation” with one another.

“If we continue searching, new clues will certainly unveil themselves. Now it’s a matter of mastering the political and societal power to preserve these precious populations in the wild and continue enabling scientists to look further.”

In humans, warfare and territoriality have traditionally been considered male “business.” Chimpanzees, with whom we share this propensity for out-group hostility and territoriality, are thought to follow the same gender difference. This vision may be too simplistic, as suggested by an international team of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. They extensively studied several neighboring groups of western chimpanzees and their findings reveal that females and even the entire group may play a more important role in between-group competition than previously thought. They found that even though adult males seem important in territory increase, territory maintenance and competitive advantage over neighbors act through the entire group in this population of chimpanzees in the Taï National Park: here.

Chimpanzees, new research


This 2015 video from Africa says about itself:

This amazing video documents the story of Wounda, one of the more than 160 chimpanzees living at the Jane Goodall Institute’s Tchimpounga Chimpanzee Rehabilitation Center in the Republic of Congo.

Thanks to the expert care provided at Tchimpounga, Wounda overcame significant adversity and illness and was recently relocated to Tchindzoulou Island, one of three islands that are part of the newly expanded sanctuary. Dr. Jane Goodall was on hand to witness Wounda’s emotional release, and now you can too.

Disclaimer: Please note, that Dr. Goodall and the Jane Goodall Institute do not endorse handling or interfering with wild chimpanzees.

Termite fishing by chimpanzees was thought to occur in only two forms with one or multiple tools, from either above-ground or underground termite nests. By carefully observing the techniques required to termite fish at ten different sites, researchers have created a catalog of behaviors for each chimpanzee in the study: here.

Researchers have systematically investigated developmental milestones in wild chimpanzees of the Taï National Park (Ivory Coast) and found that they develop slowly, requiring more than five years to reach key motor, communication and social milestones. This timeframe is similar to humans, suggesting slow maturation of the brain: here.

How wild apes react to camera traps


This November 2013 video says about itself:

Apes of East Africa

Tracking chimpanzees in Tanzania and mountain gorillas in Rwanda.

From the Max Planck Institute for Evolutionary Anthropology in Germany:

Wild African ape reactions to novel camera traps

African wild apes notice and often react to novel items in their environment

March 14, 2019

An international team of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, analyzed video from remote camera-trap devices placed in ape-populated forests throughout Africa to see how wild apes would react to these unfamiliar objects. Responses varied by species, and even among individuals within the same species, but one thing was consistent throughout: the apes definitely noticed the cameras.

“Our goal was to see how chimpanzees, bonobos, and gorillas react to unfamiliar objects in the wild since novel object experiments are often used in comparative psychology research, and we wanted to know if there were any differences among the three great apes,” says Ammie Kalan, a primatologist at the Max Planck Institute for Evolutionary Anthropology. “We were specifically surprised by the differences in reactions we observed between the chimps and bonobos. Since they’re sister species and share a lot of the same genetic makeup, we expected them to react similarly to the camera, but this wasn’t the case.”

“The chimpanzees were overall uninterested in the camera traps — they barely seemed to notice their presence and were generally unbothered by them,” Kalan says. “Yet the bonobos appeared to be much more troubled by camera traps; they were hesitant to approach and would actively keep their distance from them.”

Individuals within a species reacted differently to the cameras as well. For example, apes living in areas with more human activity, such as near research sites, can get desensitized to unfamiliar items and become indifferent toward such encounters in the future. However, another member of the same species who has had less exposure to strange or new items, might be more interested in them. The age of the ape plays a similar role. “Younger apes would explore the camera traps more by staring at them for longer periods of time,” Kalan says. “Like human children, they need to take in more information and learn about their environment. Being curious is one way of doing that.”

The range of responses shown by the apes, and the complex differences both between species and within a single species, demonstrates a need for scientists to consider how animals will respond to the presence of unfamiliar monitoring equipment in their natural habitats. “The within and between species variation in behavior towards the unfamiliar items might be problematic when trying to collect accurate monitoring data,” Kalan says. “To curb this effect, it would be worth having a familiarization period, where the wild animals can get used to the new items.”

Despite this potential complication, using camera traps to monitor populations of animals in the wild is still one of the most useful options. “Our knowledge tends to be limited by the number of groups or number of populations we’re able to study, but using monitoring technology like camera traps is an effective way of solving that problem,” Kalan says. “I think it’s really interesting from a behavioral flexibility perspective to consider how wild animals react to these new technologies. I would love for more researchers to investigate novelty responses while doing monitoring surveys.”

Chimpanzee conservation also helps other animals


This 2015 video is about the Niokolo-Koba National Park in Senegal.

From Purdue University in the USA:

In developing nations, national parks could save endangered species

March 7, 2019

Summary: A new study of animal populations inside and outside a protected area in Senegal, Niokolo-Koba National Park, shows that protecting such an area from human interaction and development preserves not only chimps but many other mammal species.

The West African chimpanzee population has declined by nearly 80 percent in recent decades. Habitat loss is threatening their livelihoods across the continent, and especially in Senegal, where corporate mining has started eating up land in recent years.

The geographical distribution of West African chimps overlaps almost perfectly with gold and iron ore deposits, and unfortunately for the chimps, mining is a key piece of the country’s development strategy, said Stacy Lindshield, a biological anthropologist at Purdue University.

Extractive industries are already improving people’s livelihoods and promoting investment and infrastructure development, and researchers are trying to find a way to protect Senegal’s chimps without surrendering these benefits. Many of Earth’s animal species are now dying off at accelerated rates, but as human’s closest living relatives, they tend to tug at our heart strings. Chimps are scientifically important, too — because they participate in collective activities such as hunting and food-sharing, they’re often studied by social science researchers.

A new study of animal populations inside and outside a protected area in Senegal, Niokolo-Koba National Park, shows that protecting such an area from human interaction and development preserves not only chimps but many other mammal species. The findings were published in the journal Folia Primatologica.

“We saw the same number of chimpanzee species inside and outside the park, but more species of carnivores and ungulates in the protected area,” Lindshield said.

Although habitat loss is the biggest threat to West African chimps, they’re sometimes killed for meat. This is uncommon in Senegal, where eating chimpanzee meat is a taboo — people think chimps are too similar to humans to eat. But this isn’t the case in other West African countries, where researchers might see a bigger difference in chimp populations inside and outside protected areas. National parks could be especially effective at protecting chimps in these nations.

The difference in the number of species of carnivores and hooved animals (known as ungulates), inside and outside the park was stark — their populations were 14 and 42 percent higher in the park, respectively. This is in sharp contrast with what Lindshield was hearing on the ground in Senegal: There’s nothing in the park; all the animals are gone.

“There were qualitative and quantitative differences between what people were telling me and what I was seeing in the park,” she said. “Niokolo-Koba National Park is huge, and the area we study is nestled deeply in the interior where it’s difficult for humans to access. As a consequence, we see a lot of animals there.”

Hunting practices and human-carnivore conflict are two big reasons for ungulates thriving inside the park. These animals are frequently targeted by hunters, and some carnivore species turn to livestock as a food source when their prey species are dwindling, creating potential for conflict with humans. Because the two sites are relatively close geographically and have similar grassland, woodland and forest cover, the researchers think human activity is the root of differences between the two sites.

Lindshield’s team conducted basic field surveys by walking around the two sites and recording the animals they saw. They also installed camera traps at key water sources, gallery forests and caves to record more rare and nocturnal animals.

“We’re engaging in basic research, but it’s crucial in an area that’s rapidly developing and home to an endangered species,” Lindshield said. “This provides evidence that the protected area is effective, at least where we are working, counter to what I was hearing from the public. The management of protected areas is highly complex. Myriad challenges can make management goals nearly impossible, such as funding shortfalls or lack of buy-in from local communities, but I think it’s important for people to recognize that this park is not a lost cause; it’s working as it’s intended to at Assirik, especially for large ungulates and carnivores.”

Lindshield hopes her future studies will uncover not only which species exist in each site, but population sizes of each species. This metric, known as species evenness, is a key measure of biodiversity.

Data from the unprotected area in Senegal was collected by Jill Pruetz of Texas State University. Stephanie Bogart and Papa Ibnou Ndiaye of the University of Florida, and Mallé Gueye of Niokolo-Koba National Park, also contributed to this research. Funding was provided by the National Science Foundation, National Geographic Society, Leakey Foundation, Rufford Foundation, Primate Conservation Inc., Jane Goodall Research Center at University of Southern California, Purdue and Iowa State University.

Working memory is central to our mental lives; we use it to add up the cost of our shopping or to remember the beginning of this sentence at its end. Some scientists argue it is particularly developed in humans, but how do chimpanzees, one of our closest relatives, compare? Researchers set out to answer this question: here.

Scientists have developed new artificial intelligence software to recognize and track the faces of individual chimpanzees in the wild. The new software will allow researchers and wildlife conservationists to significantly cut back on time and resources spent analyzing video footage, according to the new article: here.

Researchers report on the average life expectancy of chimpanzees in Japan. The average life expectancy of chimpanzees who reach adulthood — reported as 12-years-old in the paper — is 40 years: 41.5 years for males and 39.2 years for females: here.

European apes, why extinct?


This 11 December 2018 video says about itself:

Today, our closest evolutionary relatives, the apes, live only in small pockets of Africa and Asia. But back in the Miocene epoch, apes occupied all of Europe. Why aren’t there wild apes in Europe today?

Special thanks to https://AfricanFossils.org for allowing us to use their images of Proconsul and Ekembo fossils.

Ancient ape fossil discovery in India


This 13 February 2018 video from India is called Ramapithecus: Phylogenetic and Taxonomic status.

From PLOS:

Late Miocene ape maxilla (upper jaw) discovered in western India

Discovery extends the range of ancient apes in the subcontinent

November 14, 2018

An ape maxilla (upper jaw) from the Late Miocene found in the Kutch basin, in western India, significantly extends the southern range of ancient apes in the Indian Peninsula, according to a study published in November 14, 2018 in the open-access journal PLOS ONE by Ansuya Bhandari from the Birbal Sahni Institute of Palaeosciences, Lucknow, India, and colleagues.

Apes, or hominoids, are a group of primates from Africa and Southeast Asia that includes the gibbons and the great apes: chimps, orangutans, gorillas, and humans. Ancient ape remains from Miocene deposits in the Siwaliks of India and Pakistan have been key for understanding the evolution of great apes and humans. In this study, the researchers examined an ape jaw fragment excavated from the Kutch basin, in the Gujarat state of western India, about 1000 km south of the Siwaliks deposits.

X-ray computed-tomography revealed details of the preserved canine and cheek teeth, such as the tooth enamel and root structure. The ape mandible belonged to an adult individual of the Sivapithecus genus, but the species could not be identified. The authors dated the specimen to the basal Late Miocene, around 11 to 10 million years ago based on previous mammalian fossil findings in the site. The new finding is the first Miocene ape fossil to be discovered so far south in the Indian peninsula, and extends the southern range of ancient apes in the subcontinent by about 1000 km.

The authors add: “This is a landmark discovery of 11 million-year-old human ancestors in Kutch, Gujarat.”

Chimpanzees, BBC video


This 7 November 2018 video says about itself:

Things to Know About Chimps | BBC Earth

Chimp behaviour can be surprisingly advanced, and sometimes incredibly violent: discover some of their impressive features with the best clip from our Natural History archive.

Chimpanzees have a more elaborate and diversified material culture than any other nonhuman primate. Their behavior varies across tropical Africa in a way that does not always correspond to ecology: for instance, only West African chimpanzees, but no others, use stone and wooden hammers to crack nuts in a number of populations, despite the wide availability of hammers and appropriate nuts across the species’ range. An understanding of the extent of this behavioral diversity is crucial to help researchers understand the likely incipient traditions of our own earliest hominin ancestors: here.