The theists love to ask me: "where do you think our morals come from?"
And they presume this question is unanswerable... by the virtue of addressing morals.
But fucking why do you theists think that specifically this question is unanswerable?
Why do you presume that morals deserve or require a special treatment?
Why don't you ask me where does the hunting, running, sleeping, hands, legs, or pancreas come from?

I know why, because you know the answer to all those questions.
The same answers goes to the "morals question".