I hate the term nature vs nurture, it is misleading. That is why I say inheritance vs acquisition. All of it is biological, of course, because it all comes from our neurology. The difference is what we inherit from our genes that is essentially determined from the start vs what we acquire from our neurology adapting to environmental stimulus.
I don't believe it is accurate to talk about culture overriding biology. I don't think we have brains like iguanas that simply have more crap layered on top of them competing with our desire to be an iguana.
Here's an interesting thing; there's quite a relationship between post gestational brain development and what we consider intelligence. Complexity and variety of behavior, problem solving, socialization, and all those things. Humans have the longest period, African elephants have the second longest, and from there is a familiar list of characters like bottle nosed dolphins and chimpanzees. In case you aren't aware, post gestational brain development is referring to the amount your brain develops after you are born.
Now, it makes sense that this would relate to intelligence, because what it essentially points to is your brain's ability to develop in a way related to your environment instead of just being stuck with whatever plan was laid out in your genes. Apparently your brain never stops having some plasticity (which is why you can learn new things even when you are geriatric), but the earlier in your life, the more plastic it is, and as infant through childhood into adolescence, you adjust a lot.
What I take from this is that you don't have some higher part of your brain fighting some low part your brain. You don't have culture in one part trying to override your bestial instincts in another. Your brain never settled on the form only your genes would have given you. The fact that humans have culture, and just such variable behavior on even an individual level, is not some weird addition, not some new layer, it is the fundamental, default form for a human being. So when an evolutionary psychologist, for example, tries to talk about what our true, inherent mating habits are, I don't think that makes any sense. Human beings have, for as long as any human record shows, expressed great variety in mating habits, and I think that's because we have such a long post gestational brain development period and so much plasticity. That variety of mating habits is the true, inherent way humans work, in so far as anything can be called that.
The problem is the assumption that biology, neurology and genetics, is synonymous with inflexibility. And that's not my assumption. Oddly, that seems to be the evolutionary psychologist's popular assumption, when they should know better.