Turns out altruism is for the fish

Through a series of prosocial choice tasks, researchers reveal prosocial and antisocial characteristics in male convict cichlid fish. The fish distinguish between female breeding partners, unknown females, and rival males by adjusting their actions to either provide food for both them and the females or avoid providing food for the rival males.

source https://www.sciencedaily.com/releases/2021/03/210319080817.htm