From Steve Kearney
The reference to crows sharing information on humans regarded as a threat (2 July, p 5) reminded me of noted zoologist Konrad Lorenz’s 1966 book On Aggression.
Since reading it in 1971, I have never forgotten his description of crows using a specific call to alert other crows to the approach of a person who had threatened or harmed them in the past. That tiny brain demonstrating such communication and facial recognition skills makes the relatively large human brain look remarkably inefficient.
Tyers, Victoria, Australia
