Do Animal Emotions mimic human tears?

Do Animals Weep When Sadness Overwhelms Them? 

While humans are generally regarded as the only species known to cry from emotional distress, other animals undeniably produce tears. However, the purpose of these tears is often vastly different. In December, a video clip of a bison seemingly "crying," which photographer Chris Henry captured, went viral on Instagram, gaining significant attention. Indeed, the clip garnered over eight million views and sparked numerous discussions. Consequently, this raised a fundamental question: can bison truly experience sorrow? Furthermore, do non-human species ever shed tears because they feel sad? 

Tears, first and foremost, fulfil a functional purpose for vision across numerous species. For instance, many mammals, birds, and reptiles possess tear glands. These glands release a liquid solution that keeps their eyes healthy. Moreover, the precise chemical composition of these tears differs between species. Evidently, this is because they are adapted to their specific environments. 

Specifically, tears usually fall into three distinct categories. Initially, basal tears provide essential eye maintenance. These tears naturally form a protective and nourishing layer on the cornea. Secondly, reflex tears arise in response to external irritants or injuries. For example, these could be caused by exposure to extreme cold or substances like onion fumes. Therefore, they act as a cleansing mechanism. Finally, emotional tears result from psychological states. Historically, many societies considered crying from sadness a uniquely human trait. In fact, some cultures even believed that producing emotional tears could determine whether an individual was a witch or a werewolf. 

The Science of Tears: More Than Just Sadness 

Although their precise purpose remains unclear, various theories suggest that crying helps individuals navigate distress. For example, crying might signal emotional pain or vulnerability. Furthermore, tears influence social dynamics, encouraging cooperation and fostering care. In addition, they might even deter aggression. Current scientific consensus maintains, however, that emotional tears are uniquely human. Nevertheless, some observations hint at similar occurrences in other species. Therefore, it is important to carry out further study. 

For instance, while many mature animals avoid showing signs of weakness, young animals often emit tearless cries. Because of this, they attract their mother’s attention. Additionally, in deer, stressed or hungry fawns release secretions from a gland beneath the eye. As a result, they prompt maternal responses. In adulthood, however, this same gland serves a different function, namely emitting scents into the surroundings. 

Anecdotal Evidence Versus Scientific Validation 

Furthermore, there are anecdotal accounts of animals appearing to cry due to distress. Examples include elephants, a grieving gorilla named Koko, and wolves left behind by their pack. Nonetheless, scientific research has yet to validate these claims. For example, a 1985 systematic study surveyed professionals, such as veterinarians and zookeepers. In this study, they found no confirmed instances of animals crying emotionally. 

Recent studies, in contrast, provide more nuanced insights into animal tear production. A 2022 study investigated watery eyes in dogs, a familiar phenomenon to dog owners. The researchers discovered that canines produce tears during seemingly positive emotional experiences, such as reuniting with their owners. Moreover, this reaction is triggered by oxytocin, the hormone linked to bonding. Furthermore, research indicated that humans respond to these teary-eyed dogs with greater affection and a stronger inclination to care for them. Scientists even used saline drops to enhance this effect in photographs. The results of the experiments showed that moist eyes in dogs evoke stronger protective instincts in people. In conclusion, dogs evolved to communicate through eye contact. Consequently, their ability to tear up might reinforce bonds with humans, fostering love and protection. 

Stress Tears: A Pig's Perspective 

Other research has documented instances of domestic pigs producing increased eye secretions under stressful farm conditions. As a result of this stress, red stains are left beneath their eyes. Significantly, this fluid originates from the Harderian gland, a structure present in numerous species. However, it is underdeveloped in humans. Consequently, in pigs, these secretions correlate with stress. This is evidenced by lower heart rate variability and additional distress markers, such as tail-biting and fearful behaviour around humans. Furthermore, a similar phenomenon, often referred to as "blood tears," occurs in rats. Here, stress intensifies this response. Therefore, rust-coloured streaks are often observed around the eyes. Evidently, this reaction varies based on age, environmental conditions, and overall well-being. More research is necessary, however, to clarify these connections. 

The Allure of Anthropomorphism: Projecting Human Feelings 

So, what should we conclude about the "crying bison" video? While it's impossible to determine whether the bison felt sadness, it's likely that human viewers are projecting their own emotions onto the animal. After all, this tendency, known as anthropomorphism, leads people to attribute human characteristics and behaviours to non-human creatures. To illustrate, a study exploring human perception of animals presented participants with edited images of cats, dogs, horses, chimpanzees, and hamsters. Some of the images were altered to include digitally added tears. Furthermore, the results showed that people associated tears with sadness, mirroring their reaction to human tears. Furthermore, the altered images also made the animals appear "less aggressive," "kinder," and more emotionally expressive. 

The Chauvet Cave Bison: An Ancient Precedent? 

The idea of a non-human creature shedding tears fascinates us. Indeed, we typically consider it a uniquely human action. Therefore, this perception triggers an emotional response, prompting empathy. Regarding the bison in the viral video, the Instagram caption states that it roams freely in Utah’s plains. Consequently, it appears healthy, breathes normally, and exhibits no signs of distress. In fact, it stands calmly, merely observing its surroundings. Ultimately, it's far more plausible that a gust of wind or a speck of dust irritated its eye, rather than it experiencing sorrow. 

Currently, there is no scientific evidence indicating that bison engage in emotional crying. However, dating back over 20,000 years, an artist in the Chauvet Cave in France depicted a bison that some interpret as shedding tears. Strikingly, this provides a fascinating early parallel to today's viral sensation. It is important to remember, though, that interpreting ancient art is subjective and cannot be taken as proof of emotional crying in bison. 

Understanding Animal Emotion: Beyond Human Interpretation 

Moreover, focusing solely on whether animals cry overlooks a larger issue: the complexities of animal emotion. Subsequently, scientists are developing more sophisticated ways to assess how animals feel. Therefore, they look beyond simple behaviours like tear production. 

For instance, cognitive bias tests assess whether animals display optimistic or pessimistic tendencies. In these tests, researchers train animals to associate a specific stimulus with a positive outcome, such as a food reward. Subsequently, they introduce an ambiguous stimulus. If the animal approaches the ambiguous stimulus, researchers infer that it has a positive expectation. However, if the animal avoids it, they infer a negative expectation. Scientists have used this method to assess the emotional states of animals, including dogs, rats, and sheep. 

Beyond Tears: Measuring Animal Emotion 

Furthermore, heart rate variability (HRV) offers another objective measure of emotional state in animals. HRV refers to the variation in time intervals between heartbeats. Generally, higher HRV indicates a more relaxed and adaptable state. In contrast, lower HRV is often associated with stress and anxiety. Scientists measure HRV in animals using non-invasive techniques, such as electrocardiography (ECG). Through this process, they gain insights into how animals respond emotionally to different situations. 

Moreover, hormonal analysis provides valuable information regarding stress levels in animals. Specifically, researchers often measure levels of cortisol, a hormone released in response to stress. Consequently, elevated cortisol levels can indicate that an animal is experiencing anxiety or fear. In order to measure cortisol, scientists can collect samples of blood, saliva, or even faeces. For example, studies on farm animals, such as pigs and chickens, have used cortisol levels to assess the impact of different housing conditions on their welfare. In addition, this can give us an understanding into how their emotion is affected. 

Facial Expressions: Decoding Animal Communication 

Furthermore, scientists have begun to explore the use of facial action coding systems (FACS) to analyse facial expressions in animals. FACS involves identifying and coding specific muscle movements in the face. In fact, this is a method originally developed for studying human facial expressions. Consequently, researchers have adapted FACS to study facial expressions in various animal species. These species include primates, horses, and dogs. For instance, studies have identified distinct facial expressions associated with pain and stress in horses. Therefore, this provides valuable information for assessing their welfare. 

The Case of the Crying Elephant: Grief and Social Complexity 

While scientific consensus suggests that emotional crying is uniquely human, anecdotal accounts continue to fuel the debate. For example, the story of Shirley, an Asian elephant at the Elephant Sanctuary in Tennessee, gained widespread attention. Shirley formed an incredibly strong bond with another elephant named Jenny. Sadly, when Jenny died, Shirley displayed what many observers interpreted as grief. In fact, she stood vigil over Jenny’s body for hours. Moreover, she exhibited behaviours such as rocking and touching Jenny gently with her trunk. Furthermore, some observers reported seeing tears in Shirley’s eyes. 

These stories raise compelling questions regarding the depth and complexity of animal emotions. Elephants, in particular, are known for their strong social bonds and complex communication. In addition, anecdotal accounts suggest that they may experience grief in a way that is similar to humans. However, it is essential to remember that anecdotes are not scientific evidence. More research is necessary to fully understand the emotional lives of elephants and other animals. 

Unveiling Animal Grief: A Complex Puzzle 

The scientific investigation of grief in animals remains challenging. After all, emotions are inherently subjective experiences. Moreover, it can be difficult to translate those experiences into objective, measurable data. Nevertheless, researchers are using a variety of methods to study grief-like behaviours in animals. 

For instance, studies of primates have documented behavioural changes following the death of a group member. These changes include increased proximity seeking, decreased grooming, and changes in vocalisation patterns. Similarly, research on domestic animals, such as dogs and cats, has shown that they can exhibit signs of grief after the loss of a companion animal or human caregiver. These signs include changes in appetite, sleep patterns, and activity levels. Furthermore, some dogs may become withdrawn or depressed. 

Ultimately, the interpretation of these behaviours remains a subject of ongoing debate. Do these behaviours truly represent grief, or are they simply responses to a change in the animal's social environment? More research is necessary to fully understand the underlying mechanisms. 

Communication Beyond Words: The Nuances of Animal Signals 

Furthermore, understanding animal communication is crucial for interpreting their emotional states. Animals communicate in a variety of ways, including vocalizations, body language, and scent marking. For example, dogs use a wide range of vocalizations, such as barks, growls, and whines, to communicate different emotions. Moreover, their body language, including tail wags, ear position, and posture, can provide additional information about their emotional state. 

Similarly, cats communicate through meows, purrs, and hisses. In addition, their body language, including tail position, ear position, and pupil dilation, can convey different emotions. Deciphering these subtle cues is essential for understanding what animals are feeling. 

The Ethical Considerations of Animal Emotion Research 

The study of animal emotion raises important ethical considerations. It is essential to conduct research in a way that minimises stress and harm to animals. For instance, researchers should use non-invasive methods whenever possible. In addition, they should ensure that animals have access to appropriate housing, food, and social interaction. 

Furthermore, it is vital to consider the potential implications of research findings. If we discover that animals are capable of experiencing complex emotions, this could have significant implications for how we treat them. This could then affect how we treat animals, which may involve changes in farming practices and in animal research. 

Looking Ahead: Future Directions in Animal Emotion Research 

Therefore, future research should focus on developing more sophisticated methods for assessing animal emotions. These methods should be based on a combination of behavioural, physiological, and neurological measures. In addition, researchers should strive to understand the underlying neural mechanisms of animal emotions. This includes identifying the brain regions and neural circuits involved in processing different emotions. 

Moreover, it is essential to conduct more comparative research across different species. By comparing the emotional lives of different animals, we can gain a better understanding of the evolution of emotion. Thus, we will also understand the functions that emotions serve. 

The Bison Video Revisited: A Lesson in Interpretation 

Returning to the original question of the "crying bison" video, it is crucial to exercise caution when interpreting animal behaviour. While it is tempting to project human emotions onto animals, this can lead to inaccurate and misleading conclusions. Instead, we should strive to understand animal behaviour in its own context. In other words, this involves considering the animal's species, individual history, and current environment. 

It is important to remember that animals may express emotions in ways that are different from humans. For instance, they may not cry emotional tears, but they may express grief or distress through other behaviours, such as changes in vocalizations or body language. 

The Ongoing Quest for Understanding 

The question of whether animals experience emotions, such as sadness, is a complex and fascinating one. While current scientific evidence suggests that emotional crying may be uniquely human, this does not mean that animals are incapable of experiencing emotions. 

On the contrary, research has shown that animals are capable of experiencing a wide range of emotions, including joy, fear, anger, and grief. Therefore, these emotions play an important role in their social lives and survival. The more we learn about animal emotions, the better we can understand and appreciate the complexity of their lives. The research will therefore benefit humanity. 

A Call for Empathy and Respect 

Ultimately, the question of whether animals cry emotional tears is less important than the broader issue of how we treat animals. Whether or not animals experience emotions in the same way as humans, they are still sentient beings who are capable of experiencing pain and suffering. 

Therefore, we have a moral obligation to treat them with empathy and respect. This includes providing them with appropriate housing, food, and veterinary care. In addition, it involves protecting them from cruelty and exploitation. If we can treat all living creatures with respect, the world would be a far better place. 

Conclusion: Embracing the Mystery of Animal Emotion 

In conclusion, while the viral video of the "crying bison" sparked an interesting debate, it highlights the challenges of understanding animal emotions. As we have explored, scientists are developing sophisticated methods to assess animal emotional states, moving beyond anthropomorphic interpretations. These methods include cognitive bias tests, heart rate variability measurements, hormonal analysis, and facial action coding systems. 

Although emotional tears, as we experience them, might be a uniquely human trait, the animal kingdom displays a wide range of emotional expressions. Animals experience emotions in a way that is essential for their survival and social interactions. Understanding these emotions requires careful observation, rigorous scientific investigation, and a deep sense of empathy. As we continue to learn more about the emotional lives of animals, we are reminded of the interconnectedness of all living beings. Moreover, it reminds us of our responsibility to treat them with compassion and respect. 

Therefore, the next time you see an animal exhibiting behaviour that seems emotional, remember the complexities involved. Instead of immediately projecting human feelings, consider the scientific evidence and the animal's unique perspective. In doing so, we can foster a greater understanding and appreciation for the rich emotional lives of animals.