Is it true that there is no absolute morality?

[Angrboda]

Morality is an instinct like any other.  Just as we have a preference for sweet and fatty foods based on our evolutionary heritage, our moral systems appear to come preloaded with "orientations."  These orientations aren't necessarily fixed, objective, and absolute, just as what types of sweet and fatty foods appeal to us aren't fixed, but neither is it arbitrary, meaning that it has no inherent bias towards any perspective.  It's not random, in other words.

Certainly people have their own built in morality; empathy. But it's different for each person, it won't be the same for every person. It is arbitrary.

As evolved animals with social impulses, our instincts are biased towards certain ends by the process of evolution. Morality, at its most basic, is valuing some things over others. Our preferences may vary widely, but that doesn't make our preferences arbitrary. Do you feel that the preferences of morality are completely without bias towards certain ends rather than others? Because that's what arbitrary would mean.