It is often assumed that humans are inherently selfish, and cultural norms and practices have to override these tendencies to enable altruistic behavior. Specifically, young children are thought to be driven mainly by immediate selfish motivations, acquiring altruistic behaviors through the internalization of social norms or being rewarded for socially desired behavior. Moreover, it has been argued that our closest evolutionary relatives are motivated by selfish interests alone, not caring about the needs of others. This comparative evidence would lend further support for the notion that human-unique cultural factors are foundational. However, I present recent work with young children and chimpanzees that indicates that human altruism might have deeper roots in ontogeny and phylogeny. I will summarize these studies to entertain the possibility that human altruism is not due to cultural practices alone, but reflects a biological predisposition that we might share with our closest evolutionary relatives.