How Mice Provide Life-Saving First Aid to Their Unconscious Friends

Researchers have noticed some surprising behaviors in young mice. When a mouse sees another lying still, it may act in various ways to check on its friend. This can include pawing, nibbling, or even moving its tongue.

Li Zhang from the University of Southern California and his team have been studying these moments closely. They filmed mice interacting with a familiar cage mate who had been given anesthesia and was unresponsive.

Initially, the observing mice sniff the still partner. Then, they may groom or physically poke the unmoving mouse. Some mice focus on the mouth area, even pulling out their companion’s tongue, seemingly to help clear the airway. This nurturing behavior isn’t limited to unresponsive mice; similar actions were noted when interacting with deceased companions as well.

The researchers found that these caring gestures stopped once the mouse regained consciousness. Interestingly, mice showed a greater response to familiar cage mates than to strangers. This suggests that knowing the other mouse can trigger these rescue-like behaviors.

Large mammals like elephants, dolphins, and chimpanzees are also known for helping their own in times of trouble. Dolphins, for example, have been observed guiding distressed members of their pod to the surface for air, while elephants aid injured family members. These behaviors highlight that caring isn’t just a human trait.

Studying mice in the wild is more challenging. They often hide and scatter at the slightest sign of danger, making natural observations difficult. This study shows that similar caring attitudes could exist among different species, but monitoring such actions in their natural environments is a tough task.

Oxytocin, a hormone linked to bonding, appears to play a role in these rescue behaviors. In the study, neurons that release oxytocin in the amygdala and hypothalamus were activated when mice recognized a fellow cage mate in distress. Team member Huizhong Tao mentioned that if they increased the observation time, they might see even more instances of helpful behavior.

Moreover, deactivating these neuron signals reduced the mice’s attempts to help, while activating them led to more grooming and nibbling. This consistent link between oxytocin and caregiving suggests that nurturing emotions might be wired into the brains of many mammals.

Understanding these behaviors might shed light on how groups of animals function and survive. Young mice who helped a motionless mate often observed them recovering faster than those who did not provide help. This small action can significantly impact group dynamics within their natural habitat, where quick responses can mean the difference between life and death.

While these behaviors can seem similar to human actions, scientists urge caution in making assumptions about their motivations. Nonetheless, this research shows that even small creatures may care more for their companions than previously thought.

This study also opens doors for further exploration. Researchers aim to investigate if different mouse strains show varying behaviors and whether factors like stress or living conditions affect their willingness to aid a comatose companion. The findings are detailed in Science.