Ever hear someone being called a mother hen for being worried and overprotective? That expression may turn out to be quite fitting as scientists have now discovered that a hen shows empathy if she saw her chicks in distress:
To simulate this stress, the researchers exposed hens and chicks to puffs of air (as from a keyboard-cleaning canister), causing the birds mild distress without harm or pain.
The hens, which were separated from the chicks but could see, smell and hear them, paid more attention to their surroundings when the puff of air was directed at them. But when it was directed at their chicks, the mama birds responded more intensely with a stress response equivalent to fight-or-flight behavior: The hens' heart rates increased and their external temperatures changed (even though the chicks weren't making distress calls, ruling out the possibility that this was a protective-mom response).
They also emitted a "maternal vocalization" call, which is used to call their chicks back to them, Edgar told LiveScience. "It also enhances memory formation of the chicks. Then they know what to do in these circumstances if it ever arises again," she said.
Primatologist Frans de Waal of Emory University, who wasn't involved in the study, called the findings very interesting. "Not only is the mother hen emotionally affected, she also starts calling, which seems an 'other-oriented' response. She is trying to change the situation," de Waal said.