ook at a baby human versus that of many other mammals. The baby human is the most defenseless. Why? Very few innate behaviors. Also, the epigenetics and the learned behaviors of other animals also have an instinctual component that is not driven by the much more generalized learning process that humans posses via linguistic/conceptual brains. — schopenhauer1
Since you asked, Schop, I agree with Pseudonym that you seem to be trying to draw too sharp a line here. It doesn't make sense to argue that Homo sapiens abandoned neurobiological instinct for socially-constructed desires. Sure, socially-constructed desires radically change things for humans. Yet the underlying biology continuity still exists and we can argue that linguistic culture largely serves to amplify that evolved instinctual basis rather than to somehow completely replace it.
Yes, it is possible that humans evolved to be less instinctual so as to be more open to cultural shaping. But I don't think there is much actual evidence of that being the case.
Humans are born more helpless - their brains a mass of still unwired connections - because we happened to become bipeds with narrow birth canals trying to give birth to babies with large skulls. The big brains were being evolved for sociality and a tool-using culture. So babies had to be squeezed out helpless and half developed, completing their neuro-development outside the womb - a risky and unique evolutionary step. But also then one with an exaptive advantage. In being half-formed, this then paved the way for the very possibility of complex symbolic speech as a communal activity structuring young minds from the get-go. It made it possible for culture to get its hooks in very early on.
Of course this evolutionary account is disputable. But it seems the best causal view to me. And while it says that there was undoubtedly some evolutionary tinkering with the instinctual basis of human cognition - we know babies have
added instincts for gaze-following and turn-taking, stuff that is pre-adaptive for language learning and enculturation - you would have to be arguing for a more basic erasure of instincts that are pretty fundamental for the obvious evolutionary reasons that Pseudonym outlined.
It is natural that animals would have an innate desire to procreate - have sex. And it is natural that animals would have innate behaviours that are particular to whatever parental nurturing style is their ecological recipe for species success.
These in turn might be highly varied. There are many possible procreative strategies - as you know from discussions of r vs K selection.
http://www.bio.miami.edu/tom/courses/bil160/bil160goods/16_rKselection.html
However we can make reasonable guesses about what the human instinctual basis was, and remains. Certainly a desire to have sex and an instinct for nurturing are pretty basic and hormonal. Which is enough to keep the show on the road so far as nature is concerned.
Now arguing in the other direction, I would agree that this hardwired biology is not of the "overpowering" kind popularly imagined. Culture probably does have a big say. As society becomes a level of organismic concern of its own, it can start to form views about what should be the case concerning procreation. The drivers might become economic, religious and political - these terms being a way of recognising that society expresses its being as economic, religious and political strategies.
And likewise, society might wind up turning individual humans into largely economic, religious or political creatures. We might really become incentivised to over-ride our biological urges as a result of the direction that cultural evolution is taking. This may get expressed in terms of the full variety of r vs K strategies. We might get the range of behaviour from Mormons or other cultures of "strength through big families" vs the economic individualism which turns supporting a family into a financial and personal drag (with the individual now becoming, in effect, a permanent child themselves - never wanting to grow up and so creating a new dilemma for the perpetuation of that society, as is big news in Japan).
So, in my view, it is too simplistic to draw a sharp line between biological instinct and linguistic culture in humans - especially when it comes to any hardline anti-natal agenda. Although there is certainly this added level of evolutionary complexity in play with Homo sapiens.
We are at an interesting time for humans. Society has shifted from an agricultural basis to an industrial one, and now believes it is entering an information age that really cuts itself off from its biological roots. So culture is churning out individuals with psychological structures that express that current stage in its development.
Can that mindset flourish and last? Is it realistic or out of touch? Can a society predicated on life-long infantilism survive?
It might, if we can all afford robot slaves and crack the fusion free energy problem, etc. Anything remains possible - that is, if you don't pay any attention to the underlying economics of biological existence itself. The bottom is surely about to fall out of that dream - that we aren't simply a species gorging on a short-lived windfall of fossil fuels. But that's another thread.