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Scientists have captured chimpanzees performing a bizarre ritual
Primate archaeologists say that chimps are going through their own Stone Age.

Chimpanzees in three West African countries—Guinea Bissau, Côte d’Ivoire (the Ivory Coast), and Liberia, have been observed taking part in strange behavior. They store a great number of rocks in the hollows of trees. Then, usually a male, takes one of the rocks, walks a distance away, grunts an utterance, and hurls the rock at the tree, leaving a mark on it. The rock is then placed back in the hollow to be reused in this manner again.
No chimps east of these countries have been observed doing this. What’s more, there seems to be no reason for it tied to survival. It has nothing to do with acquiring food, mating, or furthering one’s status. Researchers say it might be a unique display of male power, marking the border of their troop’s territory, or even a spiritual ritual.
A team of 80 international scientists, led by Hjalmar S. Kuhl and Ammie K. Kalan, conducted the study. Kuhl and Kalan hail from the Max Planck Institute in Germany. The team set up camera traps in four remote locations in West Africa, where they caught footage of chimps taking part in this unusual and so far, unexplained behavior. Their findings were published in Scientific Reports, part of the journal Nature.
Tool usage among chimps is commonplace. Getty Images.
The authors write, “We found four populations in West Africa where chimpanzees habitually bang and throw rocks against trees, or toss them into tree cavities, resulting in conspicuous stone accumulations at these sites.” Chimps have been known to use rocks as tools, to bash open fruits or nuts for instance. Certain groups have even been seen using sticks removed of leaves and sharpened as spears, for hunting.
But they’ve never been observed taking part in behavior outside of that tied to survival. Over time, researchers found that this so-called ritualistic practice caught on in troops where males had taken part in it, with even a few females doing so. So could it be a spiritual ritual? Researchers on Kuhl and Kalan’s team have likened the rock pilings to the types of cairns the indigenous people of these areas make.
Cairns are piles of rocks that serve many purposes. People have been making them since the Stone Age. They can signify where a battle took place or as a memorial, as a marker for a grave site, a demarcation of territory, a signpost on a path, to denote a sacred site, and much more. This discovery transformed these four places from chimpanzee viewing areas to primate archaeological sites.
Stone cairns mark a hiking trail in Germany. Getty Images.
Researcher’s write:
Stone accumulation shrines at 'sacred' trees are well described for indigenous West African peoples. Superficially, these cairns appear very similar to what has been described here for chimpanzee accumulative stone throwing sites, thus it would be interesting to explore whether there are any parallels between chimpanzee accumulative stone throwing and human cairn building, especially in regions of West Africa where the local environment is similar.
Study co-author Laura Kehoe made a statement that has caused something of an uproar. She mused, “Maybe we found the first evidence of chimpanzees creating a kind of shrine that could indicate sacred trees.” It’ll take a long time to prove such a thing, should it be true. The first major hurdle, there’s great debate in the archaeological community over what counts as a ritual, or even how to define one.
Biological anthropologist Craig Stanford of USC, has studied chimps for a long time out in the field. He told The Atlantic that there’s lots of reasons they throw stones. He called the idea of this being a religious ritual “silly.” He told The Atlantic, “Ritualized behavior is common in the animal world, and chimpanzees throw stones in many contexts.” Others say it may not be so farfetched.
Dr. Jane Goodall studied chimpanzees for 55 years, and often talks of them in terms of the “sacred.” Getty Images.
Primate cognitive psychologist Laurie Santos of Yale told Smithsonian Magazine that such behavior, “fits the definition of proto-ritualistic.” Yet, she worries that we don’t know how to interpret this behavior properly nor the context surrounding it. These great apes have been shown to use creativity and imagination before, both in captivity and the wild. For instance, young female chimps have been known to carry a stick and care for it, as if it were a doll.
Chimps can have empathy for others and follow rules set by their brethren. But there’s no evidence to point to any spiritual beliefs. Do these other humanlike behaviors open up the possibility? The world renowned primatologist Dr. Jane Goodall observed chimpanzees for 55 years in Gombe, Tanzania. She often speaks of them, one of our closest ancestors (along with bonobos), in terms of the sacred.
In her work, she’s explained instances where chimps dance near waterfalls or contemplate great storms of wind and rain with fascinated gazes. “Why wouldn’t they also have feelings of some kind of spirituality?” she asked. Some scholars, in the small but growing field of primate archaeology, even say that chimps and other tool-using primates are going through their own Stone Age, and have been for quite some time.
To see this “ritual” for yourself, click here:
Archaeologists identify contents of ancient Mayan drug containers
Scientists use new methods to discover what's inside drug containers used by ancient Mayan people.
A Muna-type paneled flask with distinctive serrated-edge decoration from AD 750-900.
- Archaeologists used new methods to identify contents of Mayan drug containers.
- They were able to discover a non-tobacco plant that was mixed in by the smoking Mayans.
- The approach promises to open up new frontiers in the knowledge of substances ancient people consumed.
PARME staff archaeologists excavating a burial site at the Tamanache site, Mérida, Yucatan.
Credit: WSU
Why cities are critical to achieving a carbon-neutral world
In May 2018, the city of Paris set an ambition to be carbon-neutral by 2050.
- Countries, governments and companies are aligning on a need for net-zero - and this is an opportunity to rethink decarbonizing our cities.
- There is no "one-size-fits-all" solution – each city's needs must be at the heart of developing integrated energy solutions.
- A city can only decarbonize through collaboration between government, the private sector, and local communities.
Japanese government appoints new "Minister of Loneliness"
While not the first such minister, the loneliness epidemic in Japan will make this one the hardest working.
Minister Tetsushi Sakamoto
- The Japanese government has appointed a Minister of Loneliness to implement policies designed to fight isolation and lower suicide rates.
- They are the second country, after the U.K., to dedicate a cabinet member to the task.
- While Japan is famous for how its loneliness epidemic manifests, it isn't alone in having one.
The Ministry of Loneliness
<iframe width="730" height="430" src="https://www.youtube.com/embed/I5FIohjZT8o" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe><p><a href="https://www.jimin.jp/english/profile/members/114749.html" target="_blank" rel="noopener noreferrer">Tetsushi Sakamoto</a>, already in the government as the minister in charge of raising Japan's low birthrate and revitalizing regional economies, was appointed this <a href="https://www.japantimes.co.jp/news/2021/02/21/national/japan-tackles-loneliness/" target="_blank" rel="noopener noreferrer">month</a> to the additional role. He has already announced plans for an emergency national forum to discuss the issue and share the testimony of lonely <a href="https://www.japantimes.co.jp/news/2021/02/12/national/loneliness-isolation-minister/" target="_blank" rel="noopener noreferrer">individuals</a>.</p><p>Given the complexity of the problem, the minister will primarily oversee the coordination of efforts between different <a href="https://www.insider.com/japan-minister-of-loneliness-suicides-rise-pandemic-2021-2" target="_blank" rel="noopener noreferrer">ministries</a> that hope to address the issue alongside a task <a href="https://www.japantimes.co.jp/news/2021/02/21/national/japan-tackles-loneliness/" target="_blank" rel="noopener noreferrer">force</a>. He steps into his role not a moment too soon. The loneliness epidemic in Japan is uniquely well known around the world.</p><p><a href="https://en.wikipedia.org/wiki/Hikikomori" target="_blank" rel="noopener noreferrer"><em>Hikikomori</em></a><em>,</em> often translated as "acute social withdrawal," is the phenomenon of people completely withdrawing from society for months or years at a time and living as modern-day hermits. While cases exist in many <a href="https://www.frontiersin.org/articles/10.3389/fpsyt.2019.00247/full" target="_blank" rel="noopener noreferrer">countries</a>, the problem is better known and more prevalent in Japan. Estimates vary, but some suggest that one million Japanese live like this and that 1.5 million more are at <a href="https://www.nationalgeographic.com/photography/article/japan-hikikomori-isolation-society" target="_blank" rel="noopener noreferrer">risk</a> of developing the condition. Individuals practicing this hermitage often express contentment with their isolation at first before encountering severe symptoms of loneliness and <a href="https://www.sciencedaily.com/releases/2020/01/200110155241.htm" target="_blank" rel="noopener noreferrer">distress</a>.</p><p><a href="https://en.wikipedia.org/wiki/Kodokushi" target="_blank" rel="noopener noreferrer"><em>Kodokushi</em></a>, the phenomenon of the elderly dying alone and remaining undiscovered for some time due to their isolation, is also a widespread issue in Japan that has attracted national attention for decades.</p><p>These are just the most shocking elements of the loneliness crisis. As we've discussed before, loneliness can cause health issues akin to <a href="https://www.inc.com/amy-morin/americas-loneliness-epidemic-is-more-lethal-than-smoking-heres-what-you-can-do-to-combat-isolation.html" target="_blank" rel="noopener noreferrer">smoking</a>. A lack of interaction within a community can cause social <a href="https://bigthink.com/in-their-own-words/how-religious-neighbors-are-better-neighbors" target="_self">problems</a>. It is even associated with changes in the <a href="https://bigthink.com/mind-brain/loneliness-brain" target="_self">brain</a>. While there is nothing wrong with wanting a little time to yourself, the inability to get the socialization that many people need is a real problem with real <a href="https://bigthink.com/mind-brain/brain-loneliness-hunger" target="_self">consequences</a>.</p>The virus that broke the camel's back
<iframe width="730" height="430" src="https://www.youtube.com/embed/Hp-L844-5k8" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe><p> A global loneliness pandemic existed before COVID-19, and the two working in tandem has been catastrophic. </p><p>Japanese society has always placed a value on solitude, often associating it with self-reliance, which makes dealing with the problem of excessive solitude more difficult. Before the pandemic, 16.1 percent of Japanese seniors reported having nobody to turn to in a time of need, the highest rate of any nation <a href="https://www.japantimes.co.jp/news/2021/02/21/national/japan-tackles-loneliness/" target="_blank" rel="noopener noreferrer">considered</a>. Seventeen percent of Japanese men surveyed in 2005 said that they "rarely or never spend time with friends, colleagues, or others in social groups." This was three times the average rate of other <a href="http://www.oecd.org/sdd/37964677.pdf" target="_blank" rel="noopener noreferrer">countries</a>. </p><p>American individualism also creates a fertile environment for isolation to grow. About a month before the pandemic started, nearly<a href="https://www.npr.org/sections/health-shots/2020/01/23/798676465/most-americans-are-lonely-and-our-workplace-culture-may-not-be-helping" target="_blank" rel="noopener noreferrer"> 3 in 5</a> Americans reported being lonely in a <a href="https://www.cigna.com/about-us/newsroom/studies-and-reports/combatting-loneliness/" target="_blank" rel="noopener noreferrer">report</a> issued by Cigna. This is a slight increase over previous studies, which had been pointing in the same direction for years. </p><p>In the United Kingdom, the problem prompted the creation of the Jo Cox Commission on Loneliness. The commission's <a href="https://www.ageuk.org.uk/globalassets/age-uk/documents/reports-and-publications/reports-and-briefings/active-communities/rb_dec17_jocox_commission_finalreport.pdf" target="_blank" rel="noopener noreferrer">final report </a>paints a stark picture of the U.K.'s situation in 2017, with millions of people from all parts of British society reporting feeling regular loneliness at a tremendous cost to personal health, society, and the economy.</p><p>The report called for a lead minister to address the problem at the national level, incorporating government action with the insights provided by volunteer organizations, businesses, the NHS, and other organizations on the crisis's front lines. Her Majesty's Government acted on the report and appointed the first Minister for Loneliness in <a href="https://time.com/5248016/tracey-crouch-uk-loneliness-minister/" target="_blank" rel="noopener noreferrer">2018</a>, <a href="https://en.wikipedia.org/wiki/Tracey_Crouch" target="_blank" rel="noopener noreferrer">Tracey Crouch</a>, and dedicated millions of pounds to battling the problem. </p><p>The distancing procedures necessitated by the COVID-19 epidemic saved many lives but exacerbated an existing problem of loneliness in many parts of the world. While the issue had received attention before, Japan's steps to address the situation suggest that people are now willing to treat it with the seriousness it deserves.</p><p>--</p><p><em>If you or a loved one are having suicidal thoughts, help is available. The suicide prevention hotline can be reached at 1-800-273-8255.</em></p>How art and design can rebuild a community
MIT professor Azra Akšamija creates works of cultural resilience in the face of social conflict.
