In new research shows that crows and other corvids "know what they know and can ponder the content of their own minds,"https://www.statnews.com/2020/09/24/crows-possess-higher-intelligence-long-thought-primarily human/",according to STAT. This is considered a cornerstone of self-awareness and shared by just a handful of animal species besides humans.
In https://science.sciencemag.org/content/369/6511/1626 published in Science, German scientists put crows through a series of puzzling tasks. During those tasks, the scientists measured neural activity in different kinds of neurons with the goal of tracking how crows were sensing and reasoning through their work. They sought to study a specific kind of thinking called sensory consciousness, and they chose birds in particular as an evolutionary history pivot.
The task is simple, but involves some high-level brain stuff: “After the crow initiated a trial, a brief visual stimulus of variable intensity appeared. After a delay period, a rule cue informed the crow how to respond if it had seen or had not seen the stimulus. [A] red cue required a response for stimulus detection (“yes”), whereas a blue cue prohibited a response for stimulus detection.”
“This would be analogous to the combined achievements of the human species when it consisted of just a few thousand individuals, versus the considerable achievements of 7 billion today.”
Source: Association of old Crows