Birds are getting more intelligent.
Birds are becoming increasingly intelligent
The flying animals are often thought to be lacking smarts but new international research tracking their evolutionary history shows that they have developed plenty of new skills over millions of years - with their brains getting bigger as a result.
Professor Tamas Szekely, of the University of Bath, said: "The average body size of birds has declined, but their brains relative to their body mass has increased, indicating enhanced cognition.
"Large brains may be linked to complex social behaviours, stunning variation in bird song and sophisticated use of tools.
"In future, we want to look at how body size and brain size have evolved in relation to changes in their behaviour, life histories and ecology. These may all relate to changes in their environment during the history of the Earth."