{"id":1001,"date":"2026-04-23T09:02:00","date_gmt":"2026-04-23T09:02:00","guid":{"rendered":"https:\/\/hyokal.com\/?p=1001"},"modified":"2026-04-23T09:02:00","modified_gmt":"2026-04-23T09:02:00","slug":"bonobos-enjoy-pretend-tea-parties-chimpanzees-think-rationally-why-apes-are-more-like-us-than-we-think","status":"publish","type":"post","link":"https:\/\/hyokal.com\/?p=1001","title":{"rendered":"Bonobos enjoy pretend tea parties, chimpanzees think rationally: why apes are more like us than we think"},"content":{"rendered":"<p><\/p>\n<div>\n<p class=\"dcr-130mj7b\"><span style=\"color:var(--drop-cap);font-weight:500\" class=\"dcr-15rw6c2\">C<\/span>Leah&#8217;s plastic cups and pitcher were displayed on a wooden table in Des Moines, Iowa. Invisible juice was poured and presented to Kanzi. Kanzi eagerly picked out a fake filled cup while playing with the visiting man. In many ways, it was a typical scene from a child&#8217;s imaginary tea party. Kanji, 44, was the only bonobo.<\/p>\n<p class=\"dcr-130mj7b\">The experiment, conducted at the Great Apes Initiative facility in 2024, was the first to empirically test and document pretend play in great apes, and the results were published in February in the journal Science. The study joins a wide repertoire of studies over the past decade that have revealed strong similarities between great ape and human behavior, overturning long-held beliefs about how humans distinguish themselves from their closest relatives.<\/p>\n<p class=\"dcr-130mj7b\">&#8220;Our field seems to be repeating itself over and over again: when people come up with reasons why humans are special and unique, and scientists like me test those ideas, we may actually not be that special after all,&#8221; says Amalia Bastos, lead author of the study and a comparative psychologist at the University of St. Andrews in Scotland. &#8220;It means that animals are also equipped with secondary expression and imagination.&#8221;<\/p>\n<p class=\"dcr-130mj7b\">Kanji, who passed away last year, participated in several experiments with Bastos and others to test his ability to believe. &#8220;All of these trials start with saying, &#8216;Kanji, let&#8217;s play a game. Let&#8217;s find some juice.'&#8221; That way, you can at least gain as much footing verbally as possible, Bastos says.<\/p>\n<p><gu-island name=\"SelfHostedVideo\" priority=\"critical\" deferuntil=\"visible\" props=\"{&quot;atomId&quot;:&quot;6d774b0b-1e2a-4df1-83c8-e0781871d178&quot;,&quot;fallbackImage&quot;:&quot;https:\/\/uploads.guim.co.uk\/2026\/04\/09\/Evidence_for_representation_of_pretend_objects_by_Kanzi__a_language_trained_bonobo--6d774b0b-1e2a-4df1-83c8-e0781871d178-1.0.0000000.jpg&quot;,&quot;fallbackImageAlt&quot;:&quot;An experiment showing Kanzi engaging with pretend objects, by identifying a glass full of 'juice'&quot;,&quot;fallbackImageAspectRatio&quot;:&quot;16:9&quot;,&quot;fallbackImageLoading&quot;:&quot;lazy&quot;,&quot;fallbackImageSize&quot;:&quot;small&quot;,&quot;aspectRatio&quot;:1.7777777777777777,&quot;linkTo&quot;:&quot;Article-embed-MediaAtomBlockElement&quot;,&quot;posterImage&quot;:&quot;https:\/\/uploads.guim.co.uk\/2026\/04\/09\/Evidence_for_representation_of_pretend_objects_by_Kanzi__a_language_trained_bonobo--6d774b0b-1e2a-4df1-83c8-e0781871d178-1.0.0000000.jpg&quot;,&quot;sources&quot;:[{&quot;src&quot;:&quot;https:\/\/uploads.guim.co.uk\/2026\/04\/09\/Evidence_for_representation_of_pretend_objects_by_Kanzi__a_language_trained_bonobo--6d774b0b-1e2a-4df1-83c8-e0781871d178-1.0_480w.mp4&quot;,&quot;mimeType&quot;:&quot;video\/mp4&quot;,&quot;height&quot;:270,&quot;width&quot;:480,&quot;aspectRatio&quot;:&quot;16:9&quot;},{&quot;src&quot;:&quot;https:\/\/uploads.guim.co.uk\/2026\/04\/09\/Evidence_for_representation_of_pretend_objects_by_Kanzi__a_language_trained_bonobo--6d774b0b-1e2a-4df1-83c8-e0781871d178-1.0_720h.mp4&quot;,&quot;mimeType&quot;:&quot;video\/mp4&quot;,&quot;height&quot;:720,&quot;width&quot;:1280,&quot;aspectRatio&quot;:&quot;16:9&quot;},{&quot;src&quot;:&quot;https:\/\/uploads.guim.co.uk\/2026\/04\/09\/Evidence_for_representation_of_pretend_objects_by_Kanzi__a_language_trained_bonobo--6d774b0b-1e2a-4df1-83c8-e0781871d178-1.0.m3u8&quot;,&quot;mimeType&quot;:&quot;application\/vnd.apple.mpegurl&quot;,&quot;height&quot;:0,&quot;width&quot;:0,&quot;aspectRatio&quot;:&quot;16:9&quot;}],&quot;subtitleSize&quot;:&quot;medium&quot;,&quot;subtitleSource&quot;:&quot;https:\/\/uploads.guim.co.uk\/2026\/04\/09\/Evidence_for_representation_of_pretend_objects_by_Kanzi__a_language_trained_bonobo--6d774b0b-1e2a-4df1-83c8-e0781871d178-1.0.vtt&quot;,&quot;videoStyle&quot;:&quot;Loop&quot;,&quot;uniqueId&quot;:&quot;6d774b0b-1e2a-4df1-83c8-e0781871d178&quot;,&quot;caption&quot;:&quot;An experiment showing Kanzi engaging with pretend objects, by identifying a glass full of 'juice'&quot;,&quot;format&quot;:{&quot;design&quot;:10,&quot;display&quot;:0,&quot;theme&quot;:0},&quot;isMainMedia&quot;:false,&quot;role&quot;:&quot;inline&quot;}\"><\/p>\n<figure class=\"video-container loop \" data-component=\"gu-video-loop\">\n<div class=\"dcr-1h8tp0x\">\n<div class=\"dcr-1bm3fpl\"><video id=\"video-6d774b0b-1e2a-4df1-83c8-e0781871d178\" crossorigin=\"anonymous\" tabindex=\"0\" data-testid=\"self-hosted-video-player\" data-link-name=\"gu-video-loop-pause-6d774b0b-1e2a-4df1-83c8-e0781871d178\" data-chromatic=\"ignore\" preload=\"none\" loop=\"\" muted=\"\" playsinline=\"\" class=\"dcr-y4oheo\"><track kind=\"subtitles\" src=\"https:\/\/uploads.guim.co.uk\/2026\/04\/09\/Evidence_for_representation_of_pretend_objects_by_Kanzi__a_language_trained_bonobo--6d774b0b-1e2a-4df1-83c8-e0781871d178-1.0.vtt\" srclang=\"en\"\/><picture data-size=\"small\" class=\"dcr-zigv41\"><source srcset=\"https:\/\/i.guim.co.uk\/img\/uploads\/2026\/04\/09\/Evidence_for_representation_of_pretend_objects_by_Kanzi__a_language_trained_bonobo--6d774b0b-1e2a-4df1-83c8-e0781871d178-1.0.0000000.jpg?width=220&amp;dpr=2&amp;s=none&amp;crop=16%3A9\" media=\"(min-width: 980px) and (-webkit-min-device-pixel-ratio: 1.25), (min-width: 980px) and (min-resolution: 120dpi)\"\/><source srcset=\"https:\/\/i.guim.co.uk\/img\/uploads\/2026\/04\/09\/Evidence_for_representation_of_pretend_objects_by_Kanzi__a_language_trained_bonobo--6d774b0b-1e2a-4df1-83c8-e0781871d178-1.0.0000000.jpg?width=220&amp;dpr=1&amp;s=none&amp;crop=16%3A9\" media=\"(min-width: 980px)\"\/><source srcset=\"https:\/\/i.guim.co.uk\/img\/uploads\/2026\/04\/09\/Evidence_for_representation_of_pretend_objects_by_Kanzi__a_language_trained_bonobo--6d774b0b-1e2a-4df1-83c8-e0781871d178-1.0.0000000.jpg?width=160&amp;dpr=2&amp;s=none&amp;crop=16%3A9\" media=\"(min-width: 740px) and (-webkit-min-device-pixel-ratio: 1.25), (min-width: 740px) and (min-resolution: 120dpi)\"\/><source srcset=\"https:\/\/i.guim.co.uk\/img\/uploads\/2026\/04\/09\/Evidence_for_representation_of_pretend_objects_by_Kanzi__a_language_trained_bonobo--6d774b0b-1e2a-4df1-83c8-e0781871d178-1.0.0000000.jpg?width=160&amp;dpr=1&amp;s=none&amp;crop=16%3A9\" media=\"(min-width: 740px)\"\/><source srcset=\"https:\/\/i.guim.co.uk\/img\/uploads\/2026\/04\/09\/Evidence_for_representation_of_pretend_objects_by_Kanzi__a_language_trained_bonobo--6d774b0b-1e2a-4df1-83c8-e0781871d178-1.0.0000000.jpg?width=120&amp;dpr=2&amp;s=none&amp;crop=16%3A9\" media=\"(min-width: 320px) and (-webkit-min-device-pixel-ratio: 1.25), (min-width: 320px) and (min-resolution: 120dpi)\"\/><source srcset=\"https:\/\/hyokal.com\/wp-content\/uploads\/2026\/04\/Bonobos-enjoy-pretend-tea-parties-chimpanzees-think-rationally-why-apes.jpeg\" media=\"(min-width: 320px)\"\/><\/picture><\/video><\/div>\n<\/div><figcaption data-spacefinder-role=\"inline\" class=\"dcr-fd61eq\"><span class=\"dcr-1alawo7\"><svg width=\"36\" height=\"23\" viewbox=\"0 0 36 23\"><path d=\"M3.2 0l-3.2 3.3v16.4l3.3 3.3h18.7v-23h-18.8m30.4 1l-8.6 8v5l8.6 8h2.4v-21h-2.4\"\/><\/svg><\/span><span class=\"dcr-1qvd3m6\">Experiment showing that Kanzi interacts with pretend objects by identifying glasses containing &#8220;juice&#8221;<\/span><\/figcaption><\/figure>\n<p><\/gu-island><\/p>\n<p class=\"dcr-130mj7b\">In one scenario, two cups were &#8220;filled&#8221; with juice and then one was &#8220;emptied&#8221; into a jug. Kanzi was then asked to indicate which cup contained the juice. He made the correct selection on 34 out of 50 trials, suggesting that he understood the concept of pretend drinking. In another test, participants were asked to choose between real orange juice and mock juice. In 14 of the 18 trials, he chose the cup containing real juice.<\/p>\n<p class=\"dcr-130mj7b\">Kandi&#8217;s ability to pretend, to envision realities beyond the immediate reality, would have been unthinkable just a few decades ago. In the 1990s, scientists recognized that great apes were intelligent, able to solve puzzles and use tools, form strong social relationships, learn symbols and sign language, and pass mirror tests by recognizing reflexes that suggested a degree of self-awareness.<\/p>\n<p class=\"dcr-130mj7b\">But primatologists and cognitive researchers were just beginning to think about more abstract and complex issues such as great ape culture, expression, and theory of mind.<\/p>\n<figure id=\"53566bef-2651-473f-a3c3-04a2c727503e\" data-spacefinder-role=\"inline\" data-spacefinder-type=\"model.dotcomrendering.pageElements.ImageBlockElement\" class=\"dcr-173mewl\"><figcaption data-spacefinder-role=\"inline\" class=\"dcr-fd61eq\"><span class=\"dcr-1inf02i\"><svg width=\"18\" height=\"13\" viewbox=\"0 0 18 13\"><path d=\"M18 3.5v8l-1.5 1.5h-15l-1.5-1.5v-8l1.5-1.5h3.5l2-2h4l2 2h3.5l1.5 1.5zm-9 7.5c1.9 0 3.5-1.6 3.5-3.5s-1.6-3.5-3.5-3.5-3.5 1.6-3.5 3.5 1.6 3.5 3.5 3.5z\"\/><\/svg><\/span><span class=\"dcr-1qvd3m6\">Kanji in 2023. He took part in the first experiment to test pretend play in great apes. <\/span> Photo: Handout<\/figcaption><\/figure>\n<p class=\"dcr-130mj7b\">In recent years, scientists have made a number of surprising discoveries about the mental abilities of great apes. Chimpanzees and bonobos can remember past mates for decades. When presented with stronger evidence, chimpanzees rationally revise their previously held beliefs.<\/p>\n<p class=\"dcr-130mj7b\">Western lowland gorillas exhibit kissing behavior. Orangutans, bonobos, chimpanzees, and gorillas playfully tease each other. Bonobos cross social boundaries and collaborate with outsiders. And chimpanzees, like human &#8220;new age&#8221; people, have an eccentric and obsessive fascination with crystals.<\/p>\n<aside data-spacefinder-role=\"supporting\" data-gu-name=\"pullquote\" class=\"dcr-19m4xhf\"><svg viewbox=\"0 0 22 14\" style=\"fill:var(--pullquote-icon)\" class=\"dcr-scql1j\"><title>double quotes<\/title><path d=\"M5.255 0h4.75c-.572 4.53-1.077 8.972-1.297 13.941H0C.792 9.104 2.44 4.53 5.255 0Zm11.061 0H21c-.506 4.53-1.077 8.972-1.297 13.941h-8.686c.902-4.837 2.485-9.411 5.3-13.941Z\"\/><\/svg><\/p>\n<blockquote class=\"dcr-zzndwp\"><p>These amazing creatures have much more going on beneath the surface than people believe.<\/p><\/blockquote>\n<footer><cite>Christopher Krupenier<\/cite><\/footer>\n<\/aside>\n<p class=\"dcr-130mj7b\">In particular, scientists have made great strides in understanding apes&#8217; theory of mind. Once believed to be a distinctly human characteristic, theory of mind is the ability to understand that other individuals have their own thoughts, beliefs, desires, intentions, and knowledge that are different from ours.<\/p>\n<p class=\"dcr-130mj7b\">&#8220;Over the past few decades, many different research groups have provided innovative insights that support the idea that chimpanzees and other great apes are highly sensitive to social partners,&#8221; says cognitive scientist Christopher Cruppeny of Johns Hopkins University in Maryland, USA.<\/p>\n<p class=\"dcr-130mj7b\">\u201cThis is a case where 30 years ago the prevailing view was that there was no evidence at all, and today the consensus is that there is exciting potential here.\u201d<\/p>\n<figure id=\"44105319-7591-4529-82d9-eac020c1f1ed\" data-spacefinder-role=\"supporting\" data-spacefinder-type=\"model.dotcomrendering.pageElements.ImageBlockElement\" class=\"dcr-a2pvoh\"><figcaption data-spacefinder-role=\"inline\" class=\"dcr-9ktzqp\"><span class=\"dcr-1inf02i\"><svg width=\"18\" height=\"13\" viewbox=\"0 0 18 13\"><path d=\"M18 3.5v8l-1.5 1.5h-15l-1.5-1.5v-8l1.5-1.5h3.5l2-2h4l2 2h3.5l1.5 1.5zm-9 7.5c1.9 0 3.5-1.6 3.5-3.5s-1.6-3.5-3.5-3.5-3.5 1.6-3.5 3.5 1.6 3.5 3.5 3.5z\"\/><\/svg><\/span><span class=\"dcr-1qvd3m6\">Kanzi and Johns Hopkins cognitive scientist Christopher Krupenier.<\/span><\/figcaption><\/figure>\n<p class=\"dcr-130mj7b\">Scientists are still striving to truly understand the cognitive potential of our fellow primates. Humans and great apes diverged from a common ancestor between 6 and 9 million years ago. But it&#8217;s different <em>wise man <\/em>While the population has soared to 8 billion people, seven other species of great apes are struggling to survive. Bornean orangutans, Sumatran orangutans, Tapanuri orangutans, eastern gorillas, western gorillas, chimpanzees, and bonobos are all listed as endangered or endangered species. Time may be running out to fully understand their inner world.<\/p>\n<p class=\"dcr-130mj7b\">&#8220;One of the reasons we study great apes is because they are our closest relatives, so we are learning something about ourselves,&#8221; Krupenier says. &#8220;But we are working with these amazing creatures with rich spiritual lives, and there is much more going on beneath the surface than people believe.&#8221;<\/p>\n<h2 id=\"the-rational-mind\" class=\"dcr-12ibh7f\">rational mind<\/h2>\n<p class=\"dcr-130mj7b\">The Greek philosopher Aristotle once defined humans as &#8220;rational animals.&#8221; He argued that humans have a unique faculty of reason and deliberation that sets them apart from others. &#8220;But what does it actually mean to be rational?&#8221; asks comparative psychologist Hanna Schleihauf of Utrecht University in the Netherlands.<\/p>\n<p class=\"dcr-130mj7b\">One of the most important advances in recent years has been the discovery that chimpanzees modify their beliefs as the strength of the evidence changes. In a 2025 study of semi-captive chimpanzees at the Ngamba Island Chimpanzee Sanctuary in Uganda, Schleihauf and colleagues presented evolving evidence for the location of food rewards in groups of chimpanzees.<\/p>\n<p class=\"dcr-130mj7b\">&#8220;If you hold a certain belief for a certain reason, and that reason turns out to be wrong, you should actually let go of that belief,&#8221; says Schleihauf. &#8220;And this is what we tried to do with the chimpanzees.&#8221;<\/p>\n<figure id=\"c10c9b78-90cd-449e-9e82-6f5f23b7a8f4\" data-spacefinder-role=\"immersive\" data-spacefinder-type=\"model.dotcomrendering.pageElements.ImageBlockElement\" class=\"dcr-imskkt\"><figcaption data-spacefinder-role=\"inline\" class=\"dcr-1tdqfl9\"><span class=\"dcr-1inf02i\"><svg width=\"18\" height=\"13\" viewbox=\"0 0 18 13\"><path d=\"M18 3.5v8l-1.5 1.5h-15l-1.5-1.5v-8l1.5-1.5h3.5l2-2h4l2 2h3.5l1.5 1.5zm-9 7.5c1.9 0 3.5-1.6 3.5-3.5s-1.6-3.5-3.5-3.5-3.5 1.6-3.5 3.5 1.6 3.5 3.5 3.5z\"\/><\/svg><\/span><span class=\"dcr-1qvd3m6\">Chimpanzees at Uganda&#8217;s Ngamba Island Reserve prove they can rationally revise their beliefs. <\/span> Photo: Hannah Schleihauf<\/figcaption><\/figure>\n<p class=\"dcr-130mj7b\">In a series of experiments, the researchers presented chimpanzees with two boxes facing away from the subject. They rattled one box to show the food. <em>maybe <\/em>Please stay inside. At this point, the chimps chose which box they wanted. The researchers then turned the second box over so the chimpanzees could see what looked like an apple inside.<\/p>\n<p class=\"dcr-130mj7b\">The chimpanzees were then given the opportunity to choose again based on this stronger evidence. In this case, if the chimpanzees were rational, Schleihauf says, they would change their minds because &#8220;their initial choice was based on weak evidence, but then they see that there is actually strong evidence on the other side.&#8221;<\/p>\n<p class=\"dcr-130mj7b\">And the chimpanzees did. It seems that humans are not the only ones who have reason.<\/p>\n<p class=\"dcr-130mj7b\">Much of the cognitive research conducted on great apes has been conducted using individuals living in zoos or sanctuaries. Researchers say this provides a different perspective than assessing animals in the wild. Scientists can leverage years of data about specific individuals to design specialized experiments.<\/p>\n<p><gu-island name=\"SelfHostedVideo\" priority=\"critical\" deferuntil=\"visible\" props=\"{&quot;atomId&quot;:&quot;d3098729-2731-4edc-b13c-b211f062b046&quot;,&quot;fallbackImage&quot;:&quot;https:\/\/uploads.guim.co.uk\/2026\/04\/09\/Innocent_the_chimpanzee_filmed_by_Hanna_Schleihauf--d3098729-2731-4edc-b13c-b211f062b046-1.0.0000000.jpg&quot;,&quot;fallbackImageAlt&quot;:&quot;Pasa the chimp, filmed by Hanna Schleihauf. Apes recognise social partners not seen for years&quot;,&quot;fallbackImageAspectRatio&quot;:&quot;16:9&quot;,&quot;fallbackImageLoading&quot;:&quot;lazy&quot;,&quot;fallbackImageSize&quot;:&quot;small&quot;,&quot;aspectRatio&quot;:1.7777777777777777,&quot;linkTo&quot;:&quot;Article-embed-MediaAtomBlockElement&quot;,&quot;posterImage&quot;:&quot;https:\/\/uploads.guim.co.uk\/2026\/04\/09\/Innocent_the_chimpanzee_filmed_by_Hanna_Schleihauf--d3098729-2731-4edc-b13c-b211f062b046-1.0.0000000.jpg&quot;,&quot;sources&quot;:[{&quot;src&quot;:&quot;https:\/\/uploads.guim.co.uk\/2026\/04\/09\/Innocent_the_chimpanzee_filmed_by_Hanna_Schleihauf--d3098729-2731-4edc-b13c-b211f062b046-1.0_480w.mp4&quot;,&quot;mimeType&quot;:&quot;video\/mp4&quot;,&quot;height&quot;:270,&quot;width&quot;:480,&quot;aspectRatio&quot;:&quot;16:9&quot;},{&quot;src&quot;:&quot;https:\/\/uploads.guim.co.uk\/2026\/04\/09\/Innocent_the_chimpanzee_filmed_by_Hanna_Schleihauf--d3098729-2731-4edc-b13c-b211f062b046-1.0_720h.mp4&quot;,&quot;mimeType&quot;:&quot;video\/mp4&quot;,&quot;height&quot;:720,&quot;width&quot;:1280,&quot;aspectRatio&quot;:&quot;16:9&quot;},{&quot;src&quot;:&quot;https:\/\/uploads.guim.co.uk\/2026\/04\/09\/Innocent_the_chimpanzee_filmed_by_Hanna_Schleihauf--d3098729-2731-4edc-b13c-b211f062b046-1.0.m3u8&quot;,&quot;mimeType&quot;:&quot;application\/vnd.apple.mpegurl&quot;,&quot;height&quot;:0,&quot;width&quot;:0,&quot;aspectRatio&quot;:&quot;16:9&quot;}],&quot;subtitleSize&quot;:&quot;medium&quot;,&quot;subtitleSource&quot;:&quot;https:\/\/uploads.guim.co.uk\/2026\/04\/09\/Innocent_the_chimpanzee_filmed_by_Hanna_Schleihauf--d3098729-2731-4edc-b13c-b211f062b046-1.0.vtt&quot;,&quot;videoStyle&quot;:&quot;Loop&quot;,&quot;uniqueId&quot;:&quot;d3098729-2731-4edc-b13c-b211f062b046&quot;,&quot;caption&quot;:&quot;Pasa the chimp, filmed by Hanna Schleihauf. Apes recognise social partners not seen for years&quot;,&quot;format&quot;:{&quot;design&quot;:10,&quot;display&quot;:0,&quot;theme&quot;:0},&quot;isMainMedia&quot;:false,&quot;role&quot;:&quot;immersive&quot;}\"><\/p>\n<figure class=\"video-container loop element-video-immersive\" data-component=\"gu-video-loop\">\n<div class=\"dcr-1h8tp0x\">\n<div class=\"dcr-1bm3fpl\"><video id=\"video-d3098729-2731-4edc-b13c-b211f062b046\" crossorigin=\"anonymous\" tabindex=\"0\" data-testid=\"self-hosted-video-player\" data-link-name=\"gu-video-loop-pause-d3098729-2731-4edc-b13c-b211f062b046\" data-chromatic=\"ignore\" preload=\"none\" loop=\"\" muted=\"\" playsinline=\"\" class=\"dcr-y4oheo\"><track kind=\"subtitles\" src=\"https:\/\/uploads.guim.co.uk\/2026\/04\/09\/Innocent_the_chimpanzee_filmed_by_Hanna_Schleihauf--d3098729-2731-4edc-b13c-b211f062b046-1.0.vtt\" srclang=\"en\"\/><picture data-size=\"small\" class=\"dcr-zigv41\"><source srcset=\"https:\/\/i.guim.co.uk\/img\/uploads\/2026\/04\/09\/Innocent_the_chimpanzee_filmed_by_Hanna_Schleihauf--d3098729-2731-4edc-b13c-b211f062b046-1.0.0000000.jpg?width=220&amp;dpr=2&amp;s=none&amp;crop=16%3A9\" media=\"(min-width: 980px) and (-webkit-min-device-pixel-ratio: 1.25), (min-width: 980px) and (min-resolution: 120dpi)\"\/><source srcset=\"https:\/\/i.guim.co.uk\/img\/uploads\/2026\/04\/09\/Innocent_the_chimpanzee_filmed_by_Hanna_Schleihauf--d3098729-2731-4edc-b13c-b211f062b046-1.0.0000000.jpg?width=220&amp;dpr=1&amp;s=none&amp;crop=16%3A9\" media=\"(min-width: 980px)\"\/><source srcset=\"https:\/\/i.guim.co.uk\/img\/uploads\/2026\/04\/09\/Innocent_the_chimpanzee_filmed_by_Hanna_Schleihauf--d3098729-2731-4edc-b13c-b211f062b046-1.0.0000000.jpg?width=160&amp;dpr=2&amp;s=none&amp;crop=16%3A9\" media=\"(min-width: 740px) and (-webkit-min-device-pixel-ratio: 1.25), (min-width: 740px) and (min-resolution: 120dpi)\"\/><source srcset=\"https:\/\/i.guim.co.uk\/img\/uploads\/2026\/04\/09\/Innocent_the_chimpanzee_filmed_by_Hanna_Schleihauf--d3098729-2731-4edc-b13c-b211f062b046-1.0.0000000.jpg?width=160&amp;dpr=1&amp;s=none&amp;crop=16%3A9\" media=\"(min-width: 740px)\"\/><source srcset=\"https:\/\/i.guim.co.uk\/img\/uploads\/2026\/04\/09\/Innocent_the_chimpanzee_filmed_by_Hanna_Schleihauf--d3098729-2731-4edc-b13c-b211f062b046-1.0.0000000.jpg?width=120&amp;dpr=2&amp;s=none&amp;crop=16%3A9\" media=\"(min-width: 320px) and (-webkit-min-device-pixel-ratio: 1.25), (min-width: 320px) and (min-resolution: 120dpi)\"\/><source srcset=\"https:\/\/hyokal.com\/wp-content\/uploads\/2026\/04\/Bonobos-enjoy-pretend-tea-parties-chimpanzees-think-rationally-why-apes.0000000.jpeg\" media=\"(min-width: 320px)\"\/><img decoding=\"async\" alt=\"Pasa the chimpanzee photographed by Hannah Schleihauf. Great apes recognize social partners they haven't seen in years\" src=\"https:\/\/hyokal.com\/wp-content\/uploads\/2026\/04\/Bonobos-enjoy-pretend-tea-parties-chimpanzees-think-rationally-why-apes.0000000.jpeg\" loading=\"lazy\" data-chromatic=\"ignore\" class=\"dcr-l300o4\"\/><\/picture><\/video><\/div>\n<\/div><figcaption data-spacefinder-role=\"inline\" class=\"dcr-fd61eq\"><span class=\"dcr-1alawo7\"><svg width=\"36\" height=\"23\" viewbox=\"0 0 36 23\"><path d=\"M3.2 0l-3.2 3.3v16.4l3.3 3.3h18.7v-23h-18.8m30.4 1l-8.6 8v5l8.6 8h2.4v-21h-2.4\"\/><\/svg><\/span><span class=\"dcr-1qvd3m6\">Pasa the chimpanzee photographed by Hannah Schleihauf. Great apes recognize social partners they haven&#8217;t seen in years<\/span><\/figcaption><\/figure>\n<p><\/gu-island><\/p>\n<p class=\"dcr-130mj7b\">Recently, Krupenier, who is also a co-author of the Kanzi Imagination Study, tested the long-term memory of chimpanzees and bonobos kept in zoos. This is a feat made possible only because the history of past social partners is documented.<\/p>\n<p class=\"dcr-130mj7b\">The researchers held up statues of former groupmates and statues of strangers. &#8220;If they didn&#8217;t recognize them, they&#8217;d think they&#8217;d just scan these two photos the same way,&#8221; Krupenier explains. However, chimpanzees and bonobos spent more time gazing at previous social partners, based on non-invasive eye tracking.<\/p>\n<p class=\"dcr-130mj7b\">&#8220;The furthest bonobo we reached was one we hadn&#8217;t seen of two individuals in 26 years,&#8221; he says. &#8220;[The bonobo] This very strong and pronounced appearance bias was demonstrated across all trials, leading us to believe that even a quarter of a century later, we were still able to recognize these individuals. \u201d<\/p>\n<h2 id=\"cultural-diversity\" class=\"dcr-12ibh7f\">cultural diversity<\/h2>\n<p class=\"dcr-130mj7b\">But to truly understand the full range of great ape intelligence, we need to look to the wild. &#8220;Ultimately, we can actually see how their brains work when they&#8217;re in their natural environment, not interacting with human researchers, but with each other,&#8221; Schleihauf says.<\/p>\n<p class=\"dcr-130mj7b\">In the canopy of Indonesia&#8217;s Gunung Leuser National Park, primatologists recorded a surprising observation in June 2022. An adult male Sumatran orangutan known as Lacus, who lives in the Suak Balimbin study area, chewed up the leaves and stems of vines to make a paste and applied it to a deep wound on the edge of his face with his fingers.<\/p>\n<p class=\"dcr-130mj7b\">vine plant, <em>Yellow root (Fibraurea tinctoria)<\/em>)<em>, <\/em>It is locally known for its antibacterial and analgesic properties. Lacus&#8217; wound closed quickly and was fully healed within a few weeks.<\/p>\n<figure id=\"3213bfee-ea48-4113-aab7-1b97a62986cd\" data-spacefinder-role=\"showcase\" data-spacefinder-type=\"model.dotcomrendering.pageElements.ImageBlockElement\" class=\"dcr-5h0uf4\"><figcaption data-spacefinder-role=\"inline\" class=\"dcr-9ktzqp\"><span class=\"dcr-1inf02i\"><svg width=\"18\" height=\"13\" viewbox=\"0 0 18 13\"><path d=\"M18 3.5v8l-1.5 1.5h-15l-1.5-1.5v-8l1.5-1.5h3.5l2-2h4l2 2h3.5l1.5 1.5zm-9 7.5c1.9 0 3.5-1.6 3.5-3.5s-1.6-3.5-3.5-3.5-3.5 1.6-3.5 3.5 1.6 3.5 3.5 3.5z\"\/><\/svg><\/span><span class=\"dcr-1qvd3m6\">Lacus, a Sumatran orangutan, has a wound on his face and has chewed up herbs applied to it. It was the first time a wild animal had been seen using medicinal plants to treat wounds. <\/span> Photo: Suaku Project<\/figcaption><\/figure>\n<p class=\"dcr-130mj7b\">&#8220;Until now, there have been no reports of animals actively healing wounds with plants,&#8221; says study leader Isabel Romer, a cognitive biologist and primatologist at the Max Planck Institute for Animal Behavior in Germany.<\/p>\n<p class=\"dcr-130mj7b\">Professor Romer recently evaluated the playful teasing of four great ape species and compared the exploratory behavior of orangutans kept in zoos with those in the wild, finding that the former were more likely to explore objects. She says that&#8217;s natural. Because, &#8220;in the wild, orangutans have to cling to trees with at least one arm or one leg, otherwise they&#8217;ll fall off. But in zoos, orangutans are on the ground and have all their arms. It&#8217;s much easier for them to manipulate things.&#8221;<\/p>\n<p class=\"dcr-130mj7b\">The differences between apes kept in zoos and apes in the wild can be significant. But so are characteristics among communities in the wild.<\/p>\n<p class=\"dcr-130mj7b\">Christine Andrews, a professor of philosophy at the City University of New York, focuses her research on social cognition and the animal mind. Just like humans, chimpanzees have their own cultures that vary from group to group, she says. For example, in one community, &#8220;When a chimpanzee nibbles on a leaf, it means play. But in another community, when they nibble on a leaf, it means sex.&#8221;<\/p>\n<figure id=\"c1724e62-8ad0-421b-bba0-9f0ee602c59a\" data-spacefinder-role=\"inline\" data-spacefinder-type=\"model.dotcomrendering.pageElements.ImageBlockElement\" class=\"dcr-173mewl\"><figcaption data-spacefinder-role=\"inline\" class=\"dcr-fd61eq\"><span class=\"dcr-1inf02i\"><svg width=\"18\" height=\"13\" viewbox=\"0 0 18 13\"><path d=\"M18 3.5v8l-1.5 1.5h-15l-1.5-1.5v-8l1.5-1.5h3.5l2-2h4l2 2h3.5l1.5 1.5zm-9 7.5c1.9 0 3.5-1.6 3.5-3.5s-1.6-3.5-3.5-3.5-3.5 1.6-3.5 3.5 1.6 3.5 3.5 3.5z\"\/><\/svg><\/span><span class=\"dcr-1qvd3m6\">Pasa and Yoyo are best friends from Ngamba Island Reserve. Some philosophers and scientists now believe that different groups of great apes have their own cultures, similar to humans.  <\/span> Photo: Innocent Amp\u00e8re<\/figcaption><\/figure>\n<p class=\"dcr-130mj7b\">Similarly, chimpanzees in one community may use wooden hammers while another group uses stone hammers. &#8220;When chimpanzees move between these two communities, it&#8217;s important to know the difference; they have to learn what the same signals mean,&#8221; she says. This is much the same as human immigrants having to adapt to new countries.<\/p>\n<p class=\"dcr-130mj7b\">These cultural differences have profound implications for conservation strategies for endangered great apes. &#8220;Conservation is important for chimpanzees themselves and for us because of cultural differences,&#8221; Andrews said.<\/p>\n<figure id=\"75d182fd-806e-41e2-8bed-798a1ed5a05a\" data-spacefinder-role=\"richLink\" data-spacefinder-type=\"model.dotcomrendering.pageElements.RichLinkBlockElement\" class=\"dcr-47fhrn\"><gu-island name=\"RichLinkComponent\" priority=\"feature\" deferuntil=\"idle\" props=\"{&quot;richLinkIndex&quot;:43,&quot;element&quot;:{&quot;_type&quot;:&quot;model.dotcomrendering.pageElements.RichLinkBlockElement&quot;,&quot;prefix&quot;:&quot;Related: &quot;,&quot;text&quot;:&quot;Butterflies crossing oceans, moths navigating by the stars: unravelling the mysteries of insect migrations&quot;,&quot;elementId&quot;:&quot;75d182fd-806e-41e2-8bed-798a1ed5a05a&quot;,&quot;role&quot;:&quot;richLink&quot;,&quot;url&quot;:&quot;https:\/\/www.theguardian.com\/environment\/ng-interactive\/2026\/mar\/18\/butterflies-crossing-oceans-moths-navigating-stars-insect-migrations-aoe&quot;},&quot;ajaxUrl&quot;:&quot;https:\/\/api.nextgen.guardianapps.co.uk&quot;,&quot;format&quot;:{&quot;design&quot;:10,&quot;display&quot;:0,&quot;theme&quot;:0}}\"\/><\/figure>\n<p class=\"dcr-130mj7b\">In a paper published in February in the journal Learning and Behavior, Andrews raises the question of whether preserving animal cultural diversity should be a new conservation goal alongside simply conserving biodiversity.<\/p>\n<p class=\"dcr-130mj7b\">&#8220;Should culture be an important consideration when prioritizing the conservation of populations? Should we designate animals&#8217; &#8216;cultural heritage&#8217; for special protection?&#8221; she asked in the newspaper.<\/p>\n<p class=\"dcr-130mj7b\">Conservation often focuses on the absolute number of species to prevent extinction. But Andrews&#8217; research suggests that even if the species is saved, if a particular group of chimpanzees goes extinct, their unique culture could be lost forever.<\/p>\n<p class=\"dcr-130mj7b\">&#8220;If chimpanzee DNA is stored somewhere and we don&#8217;t know anything about the creature made from that DNA being a chimpanzee, then it&#8217;s not a chimpanzee. That&#8217;s a different story,&#8221; she says.<\/p>\n<p class=\"dcr-130mj7b\"><em>Click here for more coverage on age of extinction. You can also follow biodiversity reporters Phoebe Weston and Patrick Greenfield on the Guardian app for more nature coverage.<\/em><\/p>\n<\/div>\n<p>#Bonobos #enjoy #pretend #tea #parties #chimpanzees #rationally #apes<\/p>\n","protected":false},"excerpt":{"rendered":"<p>CLeah&#8217;s plastic cups and pitcher were displayed on a wooden table in Des Moines, Iowa. Invisible juice was poured and presented to Kanzi. Kanzi eagerly picked out a fake filled cup while playing with the visiting man. In many ways, it was a typical scene from a child&#8217;s imaginary tea party. Kanji, 44, was the &#8230; <a title=\"Bonobos enjoy pretend tea parties, chimpanzees think rationally: why apes are more like us than we think\" class=\"read-more\" href=\"https:\/\/hyokal.com\/?p=1001\" aria-label=\"Read more about Bonobos enjoy pretend tea parties, chimpanzees think rationally: why apes are more like us than we think\">Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":1002,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[],"tags":[2454,2448,1654,2449,2452,2450,2453,2451],"class_list":["post-1001","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","tag-apes","tag-bonobos","tag-chimpanzees","tag-enjoy","tag-parties","tag-pretend","tag-rationally","tag-tea"],"_links":{"self":[{"href":"https:\/\/hyokal.com\/index.php?rest_route=\/wp\/v2\/posts\/1001","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hyokal.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hyokal.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hyokal.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/hyokal.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1001"}],"version-history":[{"count":0,"href":"https:\/\/hyokal.com\/index.php?rest_route=\/wp\/v2\/posts\/1001\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/hyokal.com\/index.php?rest_route=\/wp\/v2\/media\/1002"}],"wp:attachment":[{"href":"https:\/\/hyokal.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1001"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hyokal.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1001"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hyokal.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1001"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}