Moral Relativism

I'm sure that I can't bring any clarification to your thoughts, but just my own feelings...My belief is that there are no moral absolutes when looking over a time continuum of several tens of thousands of years. Our primitive ancestors existed in a world where it was more than likely kill or be killed. I'm sure that some existed as cannibals, murdering and consuming their brethren. Would you consider such creatures (men) as morally bankrupt. I don't think so, they were existing in an environment where actions that today we consider immoral were necessary for survival.
Fast forward to the seventeenth century, the societal norms of slavery or serfdom were reality. Individuals existed within that framework and acted accordingly. Were they necessarily immoral? Not in the context of their time, but today if judged in retrospect they would appear immoral.
I think the concept of morality must be framed within a specific time frame. Who knows what humans 1000 years will consider immoral (polluting our environment, killing and eating animals, etc)?
Therefore, no absolute morality but rather evolving morality as society progresses (or regresses)...