Maybe we aren't the only altruistic species?
Humpback whales will sometimes rush to the rescue of other marine life when killer whales are on the hunt. This is particularly true if those humpbacks bear the scars of orca attacks from long ago, when the humpbacks themselves were juveniles and still small enough to be considered killer whale prey. A very interesting behavior that helps to shed more light on the intelligence of marine mammals - and possibly their ability to express altruism!
Head to National Geographic to read more! https://www.nationalgeographic.com/animals/article/humpback-whales-save-animals-killer-whales-explained