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Biology and Gender

A brief guide to the biology of gender and how using this is essential to countering the anti-trans campaign

Biology and gender

Our brains are formed of roughly 100 billion neurons (plus a similar number of glia cells) and each neuron can have up to 10,000 synaptic connections to other neurons which communicate via a range of neurotransmitters.  As with everything in our body the development of the brain is genetically coded but cell differentiation and development is determined by the environment each cell exists in and its relationship to this – epigenetics. This is fundamentally down to what exists within the cell but, if you regress back, our environment can play a part in this. Nutrition or trauma can for example have some effect on how we develop and ultimately behave.


Different areas of our brains are hardwired and develop to be specialised for different functions – the insula cortex for smell and taste processing, the amygdala for emotional response, the pre-frontal cortex for behaviour control and logical thinking etc… Now while each has its core hardwired function obviously how this develops and fine tunes its function over time is determined by epigenetics – i.e. external factors, including experiences of the world. And this leads us to the concept of heritability, which is the degree a biological attribute is determined by genes vs external environment (not to be confused with inheritability – the degree by which an attribute is passed down generations).


Gender identity has been shown to be hardwired into our brains with a 60% or so (1) heritability – that is at least 60% of our identity is determined by our genes and 40% is determined by external influences, such as hormones (whose creation is also genetically/epigenetically determined) and life experiences. This of course makes sense. We are born with the ability to speak but it takes a couple of years of external influence to develop a specific language (after which the primary development process shuts down). Similarly, you are born with a gender identity which may already have been influenced by hormonal epigenetic factors, but the next couple of years of ‘world experience’ fine tunes this so that by 3 you are set in your identity. Of course, you can’t override the genetics or the early micro epigenetics so you can’t change one’s core gender identity.


Gender identities exist across a wide continuous spectrum, which our society divides into two – a binary of male or female, and we are assigned one of these at birth based on our sex characteristics. However, while this works for many it doesn’t work for all and some have gender identities that significantly differ to those assigned even though they may not understand this at first. Those to whom this applies must spend time learning, experimenting and interacting with society to develop an understanding of their true gender identity and to establish a gender presentation around this that works.


Now, unravelling the confusion between sex and gender and recognising each as a separate heritable biological attribute, one physiological and the other neurological, is the key to defeating the current anti trans campaign.  Simply put if we are not born gender incongruent, that is with a biologically created gender identity that is significantly different to that assigned to us, then this must be a learnt behaviour, an ideology, which is the argument being used against transgender folks by the anti-trans lobby.


‘You are not born gender incongruent (i.e. due to biology) but are taught (or come) to believe you are gender incongruent by people pushing transgender ideology’ – just as you are not born antisemitic but learn and become antisemitic from those pushing antisemitism. And if being trans is an ideology (and only sex is biological) then we should stop kids being converted (to protect them), trans folks should not receive medical treatment (we treat biological issues not ideologies), trans folks can be converted back (so conversion therapy shouldn’t be banned) and trans folks should receive no special rights and indeed they and their dangerous ideology (that threatens women, children and humanity itself) should be eradicated.


Of course, if gender identity and gender incongruence is biological and not directly related to sex, as is well proven, (2) (3) then all of this is instantly blown out the water and the tables turned….

So the message should be that Gender Identity/Gender Incongruence is biological, neurological and heritable, not correlated with sex and is normal and this should be the mantra of the trans community and its allies.


Notes :-


1)     Multiple studies give heritability scores for gender identity and incongruence between 30% and 70% i.e. 30% to 70% dictated by genes the rest by epigenetics. The actual amount is not hugely important as the epigenetic factors have been shown to be biological too, for example hormone levels. Studies have failed to find any psychosocial basis for gender identity and incongruence – that is that it is a learnt behaviour, an ideology. In short we can safely and categorically state that gender identity and incongruence are biological and normal. 


This will, of course, inevitably raise the question of ‘cures’. Firstly diversity is a fundamental part of nature and is the driver of evolution – without it we wouldn’t exist. Gender diversity is a natural part of this and has existed as long as humans have existed. It is very dangerous to believe we know better than nature or God and that this is something that is wrong that needs curing, especially based on some artificial ideology. Secondly epigenetic behaviour is random and so gender diversity and gender incongruent people will always exist. The condition will arise no matter what. Finally to consider we can understand the immense complexities and scale of the genetics and epigenetics at work here and to be able to manipulate this without having major detrimental effects on something else is simply naïve. It seems to be easier to manipulate biological sex than it is biological gender. 


2)    One argument put against ‘gender is biological’ is that the scientific evidence is not conclusive or proven and only sex is biological (often mentioning XX and XY chromosomes). This is a frequently used tactic by those wishing to obfuscate the truth.


Firstly, there is considerable amounts of scientific evidence from many standard types of study that show a biological basis for gender identity and incongruence and that it is not intrinsically correlated to sex, while studies to show a psychosocial basis for this (i.e. prove it is a learnt behaviour) have come up with nothing, What is important here is not whether this is conclusive, as conclusiveness is an indeterminable measure, but whether there is more evidence based on thorough scientific research for one hypothesis over another. The one with the overwhelming evidence is the one that would be deemed the correct one. Here the evidence is overwhelmingly in favour of a biological basis and so the challenge to those who deny this is has to be ‘provide conclusive scientific evidence that gender identity and gender incongruence is psychosocial (i.e. learnt)’.

Secondly science knows its knowledge is never absolute and complete; only those with artificial ideologies believe in certainty of knowledge. Science is constantly discovering, because it uses testable hypotheses to probe for, add detail to and extend our knowledge of physically based phenomena. This is the opposite of those who argue around theoretical constructs, semantics, and ideological beliefs that have no physical basis. Kathleen Stock, religious and politically motivated folks and the such can argue their trans opinions and constructs as much as they like, but without supporting results of controlled repeatable tests, their hypotheses and arguments are simply hot air. Now 100 years ago science discovered that, in mammals, there seemed to be differences in chromosomes between males and females and the XX, XY binary model for sex differentiation was born. However, there were many anomalies encountered with this and further research soon showed that sex differentiation was far more complex than this and not actually binary nor XX XY chromosome based. Today we have a better though still incomplete understanding of the variance in and complexity of sex differentiation and more than enough evidence from research to conclude gender identity is biological and not psychosocial. That latter knowledge may lack detail, but that is no reason to dismiss the evidence; rather it is a reason to research further into that phenomenon. 


Finally gender is often claimed to be a social construct. However gender identity (or gender) is not a social construct but is a set of attributes hardwired into our brains by our biology and gender identities exist across a spectrum. The way we divide this spectrum into two - male and female - and the way we embellish these with cultural conventions is the social construct.

Our society divides the biological gender spectrum into two (male and female). However many other societies divide it into more - some three others up to five. Ever changing cultural conventions are then applied to each division 

3)       As gender (identity) is biological there must be drivers for its evolution. Now, from what we know today about the variation, complexities and evolutionary histories of neurological systems and behaviours and of sexual differentiation and reproduction, two drivers for the evolution of gender identity can be postulated. Firstly as predation (animals hunting and eating each other) started to evolve those animals that evolved neurological systems that maintained a ‘self image’ especially in relation to their environment could develop better more precise escape and attack behaviours improving reproductive chance. Secondly as sexual differentiation and reproduction evolved, so those who developed and maintained a neurological ‘self image’ would be able to identify who they could and could not mate with more effectively and therefore increase chances of reproductive success. As evolution made animals, their reproductive and social processes more complex so this has evolved to include not just a spectrum of gender identities but more and more wide ranging and complex gender  behaviours. However, it is important to note that neurological gender evolved and therefore develops after the physiological elements, such as sex, and therefore uses very different development biology to those involved the physiological elements (i.e. sex differentiation). The two are therefore not intrinsically tied.   It is also worth noting that the evolution of sexuality is an offshoot from the evolution of gender identity. Once we could all identify who we could and couldn’t mate with, attraction was neurologically developed as a means of further improving reproductive success.     

Sex and gender evolved at different times in evolutionary history and while they support each other the developmental biology is entirely different and they are not therefore intrinsically tied together

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