Genes and epigenetic phenomena such as culture are inextricably linked, and they evolved together to advance the genes.
Asking “Nature or nurture?” is wrong simply because the answer is nearly always “both".

This means that when we see a complex behavioral pattern, like religions, musicality, or humor, we do not need to know the degree to which the trait is based in genes. Even if a trait is transmitted partially or entirely outside the genome, we are logically justified in assuming that its broad purpose is the enhancement of genetic fitness.