Were we discussing how plants communicate with each other? Well, From “Birds Can Recognize People’s Faces and Know Their Voices” (ScienceDaily, June 22, 2012), we learn,
New research suggests that some birds may know who their human friends are, as they are able to recognize people’s faces and differentiate between human voices.
The team trained a group of pigeons to recognise the difference between photographs of familiar and unfamiliar objects. These pigeons, along with a control group, were then shown photographs of pairs of human faces. One face was of a person familiar to the birds whilst the other was of someone they had not seen before.
The experimental group birds were able to recognise and classify the familiar people using only their faces, whereas the birds without prior training failed. The results show that pigeons can discriminate between the familiar and unfamiliar people and can do this on solely using facial characteristics.
Lincoln’s lead researcher on the project, Dr Anna Wilkinson, from the School of Life Sciences, said: “Such advanced cognitive processes have rarely been observed in pigeons and suggest that they not only recognise individual humans but also know who they know — something which could be very important for survival. Some humans feed pigeons, others chase them. To know individuals and act appropriately to them is enormously advantageous.”
None of this would surprise anyone who feeds birds. The interesting part is that pigeons have usually been regarded as stupid compared to, say, starlings. One researcher, after offering various suggestions about what is going on in the starling’s head, admits,
It is notoriously difficult to get inside the black box of an animal’s brain in order to establish, for example, whether they can appreciate another’s visual perspective or even whether they have a ‘theory of mind’.
But it’s not clear that the birds need a theory of mind for the relevant tasks.
That is, recognizing the face of the person who scatters stale bread crusts need not involve speculation as to motive. And faces offer a cue that won’t be completely different tomorrow, as clothes might be.