Self-recognition, or the ability to recognize oneself in a mirror, is a cognitive capability that was long considered unique to humans and some great apes. However, in recent decades experiments have shown that some birds also possess this ability. Being able to recognize oneself in a mirror demonstrates an advanced level of intelligence and self-awareness.
Among birds, the magpie is the species most well-known for being able to pass the “mirror test” and demonstrate self-recognition. When placed in front of a mirror, magpies exhibit behaviors showing they understand that the reflection is of themselves, not another bird. Very few other species of birds have conclusively passed the mirror test.
What is the mirror test?
The mirror test is an experiment originally developed in the 1970s by psychologist Gordon Gallup Jr. to test self-awareness in animals. It involves placing a colored dot on part of the animal’s body that it can only see in a mirror. The animal is then presented with a mirror. If the animal touches or investigates the colored dot on its own body by looking in the mirror, this suggests it recognizes that the reflection is of itself.
Passing the mirror test is considered evidence that the animal possesses self-awareness and self-recognition. Humans typically pass this test by 18-24 months of age. In the 1970s, studies by Gallup showed that chimpanzees could also pass the mirror test. Since then, other great apes like orangutans and gorillas have passed as well.
The mirror test rules out simple mimicking or social responses to the mirror. To pass, the animal must clearly demonstrate it understands the mirror shows its own body, not another animal. Marking the animal’s body in a place it can’t normally see without a mirror is key to a valid test.
Magpie self-recognition
In 2008, researchers from Germany published a study that made news worldwide by providing the first robust evidence a bird species could pass the mirror test. The bird was the common magpie.
In the study, magpies were lightly anesthetized and a small colored sticker placed on their throat feathers. When the birds recovered and were presented with a mirror, the magpies noticed and purposefully scratched at the sticker on their own body while looking in the mirror. This suggested the magpies recognized the reflection was of themselves, not a fellow magpie showing aggressive markings.
The magpies did not scratch at stickers placed on top of their head, which they could not see in the mirror. This further showed the scratching behavior was linked to seeing the markings in the mirror, not just a reaction to having something placed on their feathers.
Follow-up experiments demonstrated that even after the colored dot was removed, magpies continued to scratch at the same spot when viewing themselves in a mirror. This meant the behavior was not instinctual scratching, but rather linked to the visual understanding that the mirror showed themselves with a colored marking in that location.
Researchers noted magpies are a highly intelligent species considered to be among the most cognitively advanced birds. Neurological studies show magpies have a dense concentration of neurons called the nidopallium caudolaterale within regions of the brain associated with self-awareness in apes and humans.
Other bird species and the mirror test
While magpies are the only species to conclusively pass the mirror test, some other birds have shown behaviors suggesting self-recognition is possible. However, limitations and inconsistencies in these studies mean definitive evidence is still lacking.
– Pigeons – Researchers in 1981 reported that pigeons pecked at colored dots on their bodies when looking in a mirror, suggesting they recognized their reflection. However, the findings could not be replicated in follow-up studies, even by the original authors. Most pigeon mirror studies since have shown no evidence for self-recognition.
– Parrots – Parrots sometimes exhibit behaviors like repetitive head movements when looking in a mirror that could suggest self-recognition. However, most studies conclude parrots likely do not recognize the reflection as themselves. Conclusively passing the mirror test has been hampered by difficulties marking the bird’s bodies with colored dots they cannot view without a mirror.
– Mynah birds – A 1987 study claimed mynah birds showed behavior indicating they understood mirrored markings were on their own bodies. However, follow-up research with greater controls could not replicate these findings, concluding mynah birds do not pass the mirror test.
– Crows and jays – Members of the corvid family like crows and jays are considered highly intelligent. They demonstrate some mirror inspection behaviors hinting at self-recognition. To date though, carefully controlled mirror test experiments are lacking to prove definite self-awareness.
Why self-recognition in birds matters
Demonstrating self-recognition shows an advanced cognitive ability only found in a few animals like apes, elephants, dolphins and magpies. It is associated with complex self-awareness, empathy, introspection and other higher mental faculties linked to intelligence and sentience.
Self-recognition may allow animals to distinguish their own body from others and have an understanding of “self” vs “other”. This likely provides an evolutionary advantage in terms of survival and social interaction. Human development studies show self-awareness is critical to our own advanced reasoning abilities.
Finding self-recognition in birds like magpies adds to evidence that this ability evolved separately across very different types of organisms. This means the capacity for animals to be self-aware may be more widespread than previously believed. It also demonstrates that birds and mammals evolved analogous advanced mental skills.
Studying the neuroscience and cognition behind self-recognition can provide further insight into animal intelligence and consciousness. It also allows us to reflect on the nature of mental abilities and self-identity in humans. Experiments like the mirror test represent an exciting frontier in the study of animal psychology and philosophy of mind.
Conclusion
In summary, the magpie is currently the only bird conclusively shown to be capable of self-recognition as demonstrated by passing the mirror test. This shows an advanced cognitive ability and self-awareness previously thought limited to humans, apes and a few other mammals.
Research on additional bird species hints at a possibility of self-recognition, but clear evidence through controlled mirror experiments is still lacking. The discovery of any new self-recognizing species would provide further exciting insights into animal cognition and evolution of intelligence.
