Since survival is the sine qua non, I now define the "moral behavior" as "behavior that tends toward survival".
Robert A. HeinleinOn two subjects the overwhelming majority of people regarded their own opinions as Absolute Truth, and sincerely believed that anyone who disagreed with them was immoral, outrageous, sinful, sacrilegious, offensive, intolerable, stupid, illogical, treasonable, actionable, against the public interest, ridiculous, and obscene. The two subjects were (of course) sex and religion.
Robert A. Heinlein