Today's interesting fact was generated from yesterdays fact. Caring and when we develop the trait.

Very early apparently. New born babies, on hearing other babies cry will cry in response, and will stop when the crying stops. If an infant knows someone is crying or suffering, it will become distressed. As soon as they can move, babies will attempt to move to someone who is distressed and try to comfort, by stroking or handing over a toy or a bottle.

If we have such a response, even so early in life, when would our ancestors have developed the trait? As long ago as a million years ago?