Yes, it is indeed a common belief that women live longer than men. This thing is not only a belief but has some biological bases as well. This difference in the level of life expectancy has made way for much research as it is a topic of curiosity. One theory exists that women are biologically superior because as they have an immune function which is stronger than men. This immune system is stronger due to the secretion of the estrogen hormone. Biologists have referred to this as sexual dimorphism. Sexual dimorphism means the situation where two different sexes