Living beings basically do everything for themselves (for their aims) – if you include the feelings. Even when it is said that someone acted selflessly, feelings made him do it.
Human does it to satisfy them and is rewarded by them. Partly because they stop pushing, partly because you get nice feelings when you e.g. helped others.
Therefore, one cannot really speak of an egoist who does everything for himself - but also not of an altruist because he was not acting selflessly (because of his feelings).
Anyone looking for altruism in the relevant literature will find that the role of emotions is very often lacking in all considerations and experiments, and their value, as a factor, is hardly properly assessed.