Problem: We do observe seemingly altruistic behaviors all of the time in humans (ex. giving to charity) and in nature (ex. a mother putting herself between a large predator and her cubs). So, evolutionary theorists have proposed that seemingly altruistic behavior is just a strategy that can be explained either through: Need Assignment Help?
1). kin selection (ex. helping others that are biologically related in order to help one's own genes),
2). direct reciprocity (ex. I give to you so you give to me, or "tit-for-tat"), or
3). indirect reciprocity (ex. benefits on taxes, expectations of being paid back in the future, or giving to enhance one's reputation with others).
If pro-social or cooperative behaviors or actions with another individual or individuals do not fit into one of those three categories (kin selection, direct reciprocity, indirect reciprocity), only then it can be considered to be truly altruistic; but it can be a challenge to determine if an observed behavior is truly altruistic, or just seemingly altruistic coupled with alternative, possibly hidden motives. So there is a debate about whether or not truly altruistic behaviors can possibly exist in humans and/or in nature.