In a simple experiment, researchers at the University of Chicago sought to find out whether a rat would release a fellow rat from an unpleasantly restrictive cage if it could. The answer was yes.
The free rat, occasionally hearing distress calls from its compatriot, learned to open the cage and did so with greater efficiency over time. It would release the other animal even if there wasn’t the payoff of a reunion with it. Astonishingly, if given access to a small hoard of chocolate chips, the free rat would usually save at least one treat for the captive— which is a lot to expect of a rat.
The researchers came to the unavoidable conclusion that what they were seeing was empathy— and apparently selfless behavior driven by that mental state.
"A study by Science/AAAS shows that rats preferred freeing caged rats rather than eating food placed in the cage, suggesting that the rats show empathy, a trait only previously known to primates."
Just let that sink in.
Don’t ever try to tell me that animals don’t have emotion because this explains everything, okay. Animals feel shit, maybe not as acutely to humans (because they are overridden more by instinct than anything else), but they DO feel.