If science (i.e. evolutionary psychology) can explain why I have the morality I

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If science (i.e. evolutionary psychology) can explain why I have the morality I do, does that mean morality is subjective? If what I believe about morality is just a product of my evolution and my upbringing, can I still expect other people to live up to my principles even though they may have had a different upbringing? What about myself? Can I still hold myself to my own standards or am I being deceived by my evolution into thinking it would be wrong to do so?