Like many humans, great apes may suffer from depression, stress, and other mood disorders, according to a new study conducted by scientists from Kyoto University in Japan. These results may further humanize our perspective on these remarkable creatures, enabling us to empathize with them more deeply and inspire us to take affirmative action to protect them.
The psychological plight of great apes
The researchers observed that great apes, like chimpanzees and orangutans, show peculiar behaviors when living in captivity. These behaviors seemingly emanate from a negative emotional state akin to depression or stress. This condition is significantly affecting their well-being, with a stark impact seen in their feeding, social interactions, and overall mood.
Through non-invasive saliva tests, the scientists found higher amounts of cortisol – a hormone linked to stress in humans – in the inhabitants of a nearby Kyoto zoo. Cortisol, in chronic states of elevation, can lead to various mental health disorders, such as depression and anxiety in living beings, including primates.
Strikingly human-like behaviors
Some captive primates would remain stationary and idle for long periods, displaying behaviors we humans perceive as boredom or melancholy. Occasional bursts of seemingly random aggression also suggest a high level of anxiety or frustration. The interaction between the apes and their surroundings mimicked the effects of depression in humans, dropping a crucial hint at their cognitive and emotional complexity.
Implications of the study and a path forward
Understanding this parallel in emotional states between apes and humans gives further credence to our shared evolutionary history and intricacies in mental health. More importantly, it sheds light on the dire need to improve the conditions of captivity. Ensuring that captive primates are provided with stimulating environments can prevent the development of such conditions and boosts their overall psychological well-being.
Towards more ethical treatments
These findings also mark a significant stride towards ethical animal treatment. Cognitive and emotional suffering is not exclusive to we humans, as made evident by these primates’ startlingly human-like responses to depression-like states. By treating animals ethically and recognizing their capacity for suffering, we can hope to create a world where all creatures are respected and valued.
Engagement in animal welfare initiatives has never been more critical. With our combined efforts, we can play a pivotal role in safeguarding our primate cousins’ mental health and overall well-being in captivity, manifesting our shared understanding and empathy into tangible actions. Let’s put our hands together to protect these magnificent creatures from psychological trauma, for their welfare is our responsibility too.

Sophia Martinez is a dedicated and compassionate animal welfare advocate and writer, who has been enriching the lives of pet owners and animal enthusiasts for over 15 years. At 48 years old, Sophia’s expertise spans a wide range of topics, from pet care and nutrition to wildlife conservation and ethical animal treatment. She holds a Bachelor’s degree in Veterinary Science from Cornell University, which laid the foundation for her deep understanding of animal health and behavior.
Sophia’s career as a writer began after years of working in animal shelters and veterinary clinics, where she discovered her talent for communicating complex animal care concepts in an accessible and engaging manner. Her desire to make a difference in the lives of animals led her to become a prominent contributor to a well-known online news platform, where she now serves as the lead writer for the animal category.
Through her insightful and informative articles, Sophia aims to educate the public on responsible pet ownership, the importance of preserving natural habitats, and the latest advancements in animal health research. Her work not only highlights the joys and challenges of living with animals but also advocates for a more compassionate world where all creatures are respected and valued.
In addition to her writing, Sophia is an active volunteer with several non-profit organizations focused on animal rescue and habitat conservation. She often shares her personal experiences with fostering animals and participating in wildlife rehabilitation programs, further inspiring her readers to get involved in animal welfare causes.
Sophia’s passion for animals and her commitment to advocacy shine through in every piece she writes, making her a trusted and beloved figure among animal lovers worldwide.