Sorry, it is not up to date, only 2013, nor really research from a reputable neurological journal about gender fluidity; but this article does speak from the point of view of a professor who has been teaching a class entitled "Archaeology of Sex and Gender” for many years prior to 2012 at UC Berkeley.
Thus we see from her recounting her experience, that scientists/archaeologists have known about transgenderism and the gender fluidity of ancient tribes for a long time. It used to be much harder to teach the students about these topics, but around 2012 students became a lot more accepting of this old scientific consensus.
[QUOTE=Ph.D Rosemary Joyce]
My goal is to demonstrate how archaeologists, bioarchaeologists, historians, and art historians find ways to explore sex and gender in the past, when they don’t have the luxury of just talking to people or observing their behavior.
[…] teaching this interdisciplinary course[…] has been really challenging. Trying to explain to students, most of whom have never questioned the naturalness of a simple correspondence between two sexes and two genders, how historical scholars can understand societies that recognized more than two sexes, more than two genders, takes work.
When we take the next step beyond that, to consider how sex/gender may better be understood as a fluid spectrum, I expect to face the strongest objections.
And that was true, for the first few years.[…]
When I started again in 2012, I wondered if I was just not remembering how the course had gone. The students seemed to be ahead of me from day one. The opening exercise-- simply listing how we recognize what gender or sex someone is-- was too complicated-- it was where we were supposed to end up, not begin.
This spring, the second time around after I started teaching the course again, I was certain. Things had changed-- as I said to a group of students, I now anticipate that I won’t be able to teach the course-- at least, as it is set up now. […]
Students, without my prompting, used the term “cisgender” when talking about people who understood themselves in terms of the gender they were assigned at birth. When I was introducing the concept of multiplying gender categories, before I could point out that more categories are still boxes, students proposed that gender is fluid, a spectrum. Some of them suggested that even a spectrum or continuum of gender was a problematic concept, because it presumed a single dimension of variation. From week one, there were students ahead of me[…]
Because where my endorsement of gender as fluid, multidimensional, and non-categorical came from a history of theoretical engagement, theirs came from their everyday life: who they were, who their friends were, how they imagined the world was and should be.
[…]
something unexpected happened.
Along with a group that continued to define sex as the biological ground for corresponding genders (a position I hope students will feel free to defend, even though I disagree), there was an equally large group that described gender and sex, both, as cultural conceptions that artificially enforced stable identity on a more fluid continuum or spectrum of identity. A third group said they would describe gender as a personal experience, something outside social or cultural control, an internal state that could not be assessed without the testimony of the person.
While I wasn’t teaching this material, a new generation has formed: already thinking of gender as something that should not be a categorical identity imposed on them; ready to create space for their peers, not just for their own freedom to define themselves as they feel appropriate.
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