Crows have very memories and studies have shown they can recognize a human face, and types of human behavior. Moreover, crows appear to be able to signal this to their offspring so that their young can learn. Crows and ravens often score very highly on intelligence tests. Certain species top the avian intelligence scale.
In 2015, Digital Journal reviewed research that indicated crows can seemingly solve higher-order, relational-matching tasks. Here, the findings suggested crows are one of the few non-human animals capable of “displacement” (this means communicating about things that are happening in a different space or time to where the crow is currently; that is something happening in a different location or something that has happened in the past.)
Crows are also very social creatures and appear to react when another crow, especially one from the same family unit, dies. The reaction normally results in the crow making a noise, which is distinct from its usual call.
In recent research, conducted in a Seattle parks, University of Washington researchers used carrying a stuffed crow. They then recorded the reactions of other crows to the seemingly dead bird. They found:
It takes one crow to signal an alarm.
Following this, on average, over 20 crows appear.
The crows surround the ‘dead crow’, undertaking a behavior called ‘mobbing’.
To assess what was happening, the researchers used radioactive tracers to measure the brain activity of crows after they were shown a dead bird. The data indicated that a section of the hippocampus (the region of the brain involved in memory formation) became notably active at the sight of death. The researchers took this as a clear and notable reaction, and one not commonly seen with other birds.
The findings have yet to be published in a journal, although a research note has been produced.