Moral relativism as a moral view is incoherent. That's because by suggesting to me that I shouldn't try to impose my moral values on others, you are imposing your moral values on me.Good point since this is a perfect example of how the perception of a community ideal-image facilitates destruction of the actual community. The fact is that all living things operate within an ecology/community. Humans, and maybe other animals too, however are capable of creating an abstract image of their community and attribute ideals and other attributes to it. When the goodness of community-functioning is attributed to racial/ethnic identity, genocide becomes a logical utilitarian approach to "purifying" the community to include only those considered "racially good."
Of course, other attributes besides racial/ethnic identity can also be used for "purification/cleansing" such as when people seek to "cleanse" their communities of criminals, sloths, cowards, delinquents, deviants, perverts, witches, religious fundamentalists or other stigmatized identities. Physical removal or killing of stigmatized individuals usually only occurs when attributes are defined in terms of essentialism, i.e. that certain individuals contain undesirable traits as part of their "essence." When undesirable traits are viewed as cultural and culture is viewed as learned instead of essential, resocialization may be taken as a less-violent approach to moral conflict.
Cultural/moral relativists claim that people shouldn't attempt to resocialize each other culturally, let alone attack them violently, but the question is whether total relativism is ever truly possible to the point where individuals can have radically conflicting moral and other values and still be able to interact positively and constructively. Imo, the best hope for that is for people to have guidelines or standards as to how far they may utilize social power against those they disagree with. This requires anti-discrimination laws, for example, and rights and protections against abuses of freedom.
It is a perfectly valid scientific perspective, however, to claim there is no absolute pre-determined morality in the species as a whole.