A species of magpie is the first bird found to show cooperative behaviour without prompting.

A team led by Lisa Horn at the University of Vienna devised apparatus that allowed East Asian azure-winged magpies (Cyanopica cyana) to distribute food (mealworms and crickets) to others and found that they gave out food relatively evenly to group members. The authors argue that their findings support the 'cooperative breeding hypothesis'. This states that prosocial behaviour — helping others at no or low cost — evolved in species such as humans, whose offspring are cared for by not only parents, but also other group members.

Biol. Lett. 12, 20160649 (2016)