You know, a few years back I read an article which addressed the question of why human women do not die immediately following menopause. We no longer reproduce. We use resources. What possible purpose could we serve in society post menopause?
Well, the article addressed the fact that the survival of a species involves more than just passing on genetic material. We don't exist just as individuals. We live in communities, and as members of communities, we contribute to the survival of the community via a wide range of contributions. 
The article speculated that in tribal societies, women who bore man children needed an extra set of hands to tend to the safety and well being of a large group, and that the role of the "grandmother" played a vital role in the survival of the community as a whole.
Childbearing, in spite of being obviously necessary for the survival of a community, places a huge burden on the parents as well as the larger community. It is harder to flee enemies. The mother is taken out of the larger workforce for a period of time, and her need for resources increases. General mobility of nomadic communities decreases.
There was clearly a need within ancient societies for members who are not currently reproducing, whether they are grandparents or people of childbearing age who are not bearing children.
In today's society, our structures have changed much faster than our genetic programming. Grandma lives in another state, and a the kids go to daycare when mom goes back to the office. Gay men and lesbians become parents and raise kids. Heterosexual individuals can decide if they want to parent, and have access to birth control (in many but not all societies) to limit their family size and either contribute more to work, or contribute more actively to the well-being of their smaller families.
You asked about the sources of "morals" and "emotions." I think that it is clear the empathy, and concern for the well-being of others are necessary components to survival. If a tribe needs to flee an enemy, the mother's survival would be increase if she abandoned her brood. But those who were programmed to protect their offspring were more likely to pass on the genetic material to future generations.
Unlike many here, I approach the world from a social science, rather than a hard science perspective. I welcome feedback from our hard scientists on this very interesting question.