Many (and probably most) animals also have gender in the sense that individuals with penises behave in certain ways, and individuals with ovaries behave in other ways, despite not having memes.

I think this is a cached thought. It's very easy to anthropomorphize; if scientists can do it for the concept of natural selection itself, they can certainly do it for animals. The scientific community is much less neutral than we would both like it to be, and as such, it will support findings that are more in line with the social status quo. This is something that we admit for everything that we've changed our minds about, and it doesn't seem surprising to me that we'll continue changing our minds.

I'll take it you haven't been paying attention to the discussions of status on OB and LW. In my experience rationalist are much more willing to consider explanations based on social pressure, then feminists are to consider explanations based on natural selection.

In my experience, almost all "status" conversations are based upon a hackneyed post-hoc evolutionary just-so story. Most prominent feminists are not in fact scientists, and this is the fault of our society for not being more scientific in general, not feminism specifically (what political movements are led by scientists?).

Additionally, I think when you use the word "consider," you mean "accept." Feminists do consider explanations based on evolution; they just reject them because they think another explanation is more probable. The fact that they reject them isn't very useful; what would be interesting is why, but you don't bring that up.

I think this one section also displays fairly bad mind-killing -- even if my team is bad in some way, that isn't evidence for it being wrong, and it isn't evidence for your team being right.

In general, it seems strongly that some aspects of gender are social constructs and others or not. The most helpful way of distinguishing them is to look at differences across different societies.

There are however two huge pitfalls when engaging in this sort of reasoning.

The first is the tendency to conclude that since aspect X of gender apparently doesn't exist in society Y, it is therefore a social construct, and it can be eliminated by changing some particular aspect of the existing society in isolation -- ignoring the possibility that any such change necessarily entails making the society look more similar to Y in other ways, which would be seen as unfavorable even by most people who are negatively disposed towards X per se. This of course sounds like a clear fallacy when spelled out like this, but the fallacy can often be found at the core of many gender-related arguments, and countering it is often impossible without making arguments of the sort "lack of X leads to Y" that sound insensitive and offensive when stated explicitly.

The second is the failure to realize that aspect X of gender can be a stable equilibrium for collective behavior, like driving on the right side. There is nothing (more or less) that objectively favors either the left- or the right-side driving to be the universal rule, and different conventions exist in different places, but this doesn't mean it's a good idea to start telling people that since the direction of traffic is a social convention, they should now choose freely which side to drive on. (This also relates to the first problem, since unlike the direction of traffic, different stable equilibriums in gender-related norms may in fact have far-reaching broader social implications.)

(And all this is even ignoring the common tendency to report information about other societies in distorted and biased manner in service of ideological goals, which introduces further dangers and greatly multiplies the amount of nonsense on this topic that is circulating around, even in prestigious venues.)

However, now consider for example aggressiveness. In pretty much all societies, males are considered to be more violent and aggressive than females. ... But the claim that gender as a whole is a pure social construct is empirically wrong.

Not all attributes of gender are transient; not all of the things commonly attributed to one gender or another would be totally gone in a genderless (non-transhumanist) society. But that doesn't mean that the category of gender cleaves thingspace at the natural edges.

Aside from looking at other cultures, there are other methods. For example, one can look at children who were genetically male but had surgery at a very young age that made them anatomically female. Even when they are raised as "female" they [frequently develop habits, attitudes, and play interests] that are considered to be masculine.

This isn't a good experiment unless the people involved have no knowledge of the child's birth sex. Also, as far as I'm aware, there's about one prominent case study describing this, and as such I think it's misleading that you use the word "frequently". The one time I know of this happening, you're right -- the person eventually transitioned back to masculinity. But that's not much to update on.

I didn't give any distribution for the two option-clusters I outlined. I think it's more likely that we'll end up in a patriarchal dystopia for a variety of reasons. I think that the enlightenment ideas that transhumanism claims to champion are meaningless in a patriarchal context (or a context devoid of feminist analysis).

I think you're being very eager to disagree with me, which isn't unsurprising, since politics etc..