In their new paper V Philosophical Transactions of the Royal Society BResearchers from Ruhr University Bochum Gianmarco Maldarelli and Onur Güntürkün identify three central areas in which birds show remarkable parallels with the conscious experience of mammals: sensory consciousness, neurobiological underpinnings, and accounts of self-awareness.
Maldarelli and Güntürkün show that there is growing evidence that (i) birds are sensory and self-aware, and (ii) they also have the neural architecture that may be necessary for this. Image credit: Kutte.
First, research on sensory consciousness shows that birds not only automatically process stimuli, but also subjectively experience them.
When presented with ambiguous visual stimuli, pigeons switch between different interpretations, just like humans.
Crows have also been shown to possess neural signals that do not reflect the physical presence of a stimulus, but rather the animal's subjective perception.
When a crow sometimes consciously perceives a stimulus and sometimes not, certain nerve cells respond precisely in accordance with this internal experience.
Second, the brains of birds contain functional structures that meet the theoretical requirements for conscious information processing, despite their different brain structures.
“The avian equivalent of the prefrontal cortex, the nidopallium caudolatere (NCL), is extremely connected and allows the brain to integrate and flexibly process information,” Dr. Güntürkün said.
“The avian forebrain connectome, which represents the totality of information flow between brain regions, has many similarities with mammals.”
“Birds thus meet many of the criteria of established theories of consciousness, such as the global neural workspace theory.”
Third, more recent experiments suggest that birds may have different types of self-perception.
Although some species of corvids pass the traditional mirror test, other ecologically valid versions of the tests have shown different types of self-awareness in other bird species.
“Experiments show that pigeons and chickens differentiate between their reflection in a mirror and a real member of their species and respond to them depending on the context,” Dr Güntürkün said.
“It’s a sign of situational, basic self-awareness.”
The findings suggest that consciousness is an older and more widespread evolutionary phenomenon than previously thought.
Birds demonstrate that conscious information processing is possible without a cerebral cortex and that different brain structures can achieve similar functional solutions.
_____
Gianmarco Maldarelli and Onur Güntürkün. 2025. Conscious birds. Phil. Per. R. Juice. B 380 (1939): 20240308; two: 10.1098/rstb.2024.0308
