The decision to urinate involves a complex combination of both physiological and social considerations. However, the social aspects of urination remain largely unknown. More specifically, timing urination (i.e., synchrony) and triggering urination by observing similar behavior in others (i.e., social contagion) occur in humans across different cultures. It is thought that it probably occurs in animals other than humans as well. in new paper in diary current biologyScientists have discovered that urination is socially contagious in chimpanzees, one of our closest relatives, measured through more than 600 hours of total outbreak records in 20 captive chimpanzees at Japan's Kumamoto Sanctuary. is reported. Their results suggest that socially contagious urination is an overlooked aspect of social behavior and potentially widespread.
<div id="attachment_102786" style="width: 590px" class="wp-caption aligncenter"><a href="https://cdn.sci.news/images/enlarge12/image_13596e-Chimpanzees.jpg"><img aria-describedby="caption-attachment-102786" class="wp-image-102786 size-full" src="https://cdn.sci.news/images/2025/01/image_13596-Chimpanzees.jpg" alt="A chimpanzee eats leaves in the Kumamoto Preserve. Image credit: Onishi et al., doi: 10.1016/j.cub.2024.11.052." width="580" height="436" srcset="https://cdn.sci.news/images/2025/01/image_13596-Chimpanzees.jpg 580w, https://cdn.sci.news/images/2025/01/image_13596-Chimpanzees-300x226.jpg 300w" sizes="(max-width: 580px) 100vw, 580px"/></a><p id="caption-attachment-102786" class="wp-caption-text">A chimpanzee eats leaves in the Kumamoto Preserve. Image provided by: Onishi <em>others</em>., doi: 10.1016/j.cub.2024.11.052.</p></div>
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<p>"In humans, urinating together can be considered a social phenomenon," said Kyoto University researcher Ena Onishi, lead author of the study.</p>
<p>There is an Italian proverb that says:<em>People who don't pee at work are either thieves or spies.</em>'(<em>Chi non piscia in compagnia o è un ladro o è una spia</em>), In Japanese, the act of urinating with another person is called ``.<em>connection</em>""</p>
<p>"This behavior has been expressed in art across cultures for centuries and continues to appear in modern social contexts."</p>
<p>"Our study suggests that this phenomenon may have deep evolutionary roots."</p>
<p>"We found that chimpanzees, our closest relatives, tend to urinate in response to the urination of nearby individuals."</p>
<p>Researchers decided to study this behavior after noticing that the chimpanzees at the sanctuary seemed to urinate at about the same time.</p>
<p>It reminded me of human behavior and I thought it might be comparable to a contagious yawn.</p>
<p>To find out, they recorded the urination behavior of Kumamoto chimpanzees over 600 hours, including 1,328 urination events.</p>
<p>They analyzed observational data to see if the chimpanzees' pees were significantly synchronized in time.</p>
<p>They also investigated whether it was influenced by nearby individuals or shaped by social factors.</p>
<p>The evidence showed that micturition events during observation were significantly more synchronized than would be expected if the chimpanzees simply urinated at random times on each other.</p>
<p>Physical proximity to the first urinator also increased the likelihood of contagious urination.</p>
<p>Interestingly, individuals with lower dominance rankings were more likely to pee when others were peeing.</p>
<p>This finding suggests that urinary patterns are influenced by social class and that behavior tends to flow along dominant structures.</p>
<p>"We were surprised to find that transmission patterns are influenced by social status," Dr. Onishi said.</p>
<p>"Since there have been no previous studies of contagious urination in any species, we draw parallels with contagious yawning, another semi-voluntary physiological behavior."</p>
<p>"Based on this, we initially expected that the social effects might be similar to those seen with yawns, such as stronger contagion between socially close pairs."</p>
<p>"However, our results showed no evidence of effects related to social intimacy."</p>
<p>"Instead, we observed a clear effect of social status, with lower status people being more likely to defer to others' urination."</p>
<p>"This was an unexpected and interesting result because it opens up multiple possibilities of interpretation," said lead author Dr. Shinya Yamamoto, also from Kyoto University.</p>
<p>"For example, it may reflect covert leadership in synchronizing group activities, strengthening social bonds, or attentional biases between subordinate individuals."</p>
<p>"These findings raise interesting questions about the social function of this behavior."</p>
<p><span style="color: #808080;">_____</span></p>
<p><span style="color: #808080;">Ena Onishi <em>others</em>. 2025. Socially contagious urination in chimpanzees. <em>current biology</em> 35 (2): R58-R59;doi: 10.1016/j.cub.2024.11.052</span></p>
</div>Source: www.sci.news
