Humans aren't the only animals that step up to help others out of difficult situations. In a study recently published in the journal Scientific Reports, Michaela Masilkova of the Czech University of Life Sciences and her colleagues described a boar's daring rescue of two young wild boars stuck in a trap.

Few animals show this kind of rescue behavior: to go out of their way to help other members of their species that are caught in a dangerous situation. Masilkova's team inadvertently caught an astonishing act of altruism on camera while conducting a separate experiment to monitor wild boar movement for the prevention of African Swine Fever. The goal was to catch boars so the researchers could mark them individually. The researchers set up traps containing food as lure. Once lured inside, a boar would be caged in by logs that would roll off the top of the enclosure and bar the door shut. 

One night the trap — operating as usual — snared two young boars. But the night took an unexpected turn when a new herd arrived at the scene. One adult female took particular interest in the captives' predicament. Over the course of 29 minutes, the female pushed against the logs and successfully moved it, allowing the young boars to escape. Given that the rescuer spent so much time on this activity and showed physical signs of distress throughout, the researchers believed her act to be potential evidence of pro-social empathy.

This discovery suggests that complex forms of empathy may just be more common in the animal kingdom than scientists may have previously believed.