Roosters Show Self-Awareness by Ignoring Their Own Reflection, Study

A new study by German researchers has found that roosters may be able to recognize themselves in a mirror, a key test of self-awareness in animals.

The study, published in the open-access journal, used a modified version of the mirror self-recognition test that involved observing the roosters' alarm calls in response to a simulated predator threat.

The mirror self-recognition test

(Photo : MIGUEL MEDINA/AFP via Getty Images)

The mirror self-recognition test, developed in 1970, is a widely used method to assess whether an animal has a sense of self.

The test involves placing a mark on an animal's body in a spot that can only be seen in a mirror's reflection.

The animal is then exposed to a mirror and its behavior is observed. If the animal inspects or touches the mark while looking at its reflection, it suggests that it understands that the reflection represents its own body.

However, this test has several limitations and controversies.

For one thing, not many non-human animals have passed this test, including some of the great apes, dolphins, elephants, and magpies.

For another thing, some animals may not have the motivation or the ability to investigate the mark on their body, even if they recognize themselves in the mirror.

Moreover, some animals may use other senses besides vision to identify themselves or others, such as smell or sound.

A new approach to testing self-recognition in Roosters

To overcome these challenges, Sonja Hillemacher at the University of Bonn and her colleagues devised a new approach to testing self-recognition in roosters, who are known to have complex social and cognitive abilities.

Roosters are also vocal animals that use alarm calls to warn other chickens of nearby predators but generally stay quiet when alone.

The researchers tested 68 roosters one by one in an arena divided down the middle by a wire mesh. The team placed a rooster on one side, and either left the other side empty or put another rooster in it.

The researchers added a mirror to the divider for some tests. To mimic a threat, the researchers projected the silhouette of a hawk on the ceiling above the arena.

They found that when a rooster was paired with just another rooster, it raised the alarm far more often than when it was alone in the arena, with or without seeing its reflection.

Having another rooster present but blocked from view behind a mirror led to similarly few alarms, suggesting that the roosters are distinguishing between reflection and reality through vision, not smell or sound.

The researchers concluded that since the birds act similarly when alone and with a reflection, they may realize their reflection is of themselves.

This may indicate that roosters have a sense of self-awareness or at least some form of self-representation.

Also Read: Jailed "Rooster Killer" from Florida Cries Self-Defense

Implications and Future Directions

The study is the first to show that roosters may be able to recognize themselves in a mirror using a behaviourally relevant test.

The study also demonstrated that self-recognition can be tested in different ways depending on the species and their natural behaviors.

The researchers suggested that their method could be applied to other vocal animals that use alarm calls or other signals to communicate with conspecifics, such as crows, parrots, or dogs.

They also proposed that further studies could investigate whether roosters can recognize their voice or smell, or whether they can use mirrors to access hidden food or objects.

Furthermore, the study added to the growing evidence that self-awareness is not unique to humans or a few select animals but may be more widespread and diverse than previously thought.

Understanding how different animals perceive themselves and others could shed light on the evolution and function of self-awareness and social cognition.