1,2,3,4… Crows count out loud like small children

Researcher Diana Liao and her colleagues from the University of Tübingen, Germany, imagined an original experiment.

They started by teaching three crows to croak on command. Then they trained thems “to produce one to four cries (a ‘croa’) depending on the number (1,2,3,4) presented to them or the sound they heard”, describe Science.

For example, the sound of a guitar string would produce one “croa” and a drum roll would produce three “croats”. During their learning, the sparrows were rewarded with an insect to eat when they successfully completed the exercise.