How we inherit masculine and feminine behaviours: a new idea about environment and genes

The Conversation, August 18, 2017 3.22pm AEST

What if thousands of years of gendered environments actually reduced the need to develop genetic mechanisms to ensure gender differences? This is the idea we suggest in our new paper.

Advances in evolutionary biology recognise that offspring don’t just inherit genes. They also reliably inherit all kinds of resources: a particular ecology, a nest, parents and peers. And it appears that these stable environmental factors can help ensure the reliable reproduction of a trait across generations.

What’s the point of sex? It frames gender expression and identity – or does it?

The Conversation, January 18, 2017 6.05am AEDT

The act of penetrative sex has evolved over millions of years as a mechanism to deliver sperm to eggs and initiate pregnancy. But there’s more to sex than just the meeting of two sets of genes. The ‘What’s the point of sex?’ series examines biological, physical and social aspects of sex and gender.

[This] piece looks at sexual identity and gender, and how these are expressed in a social context.

‘We don’t know if your baby’s a boy or a girl’: growing up intersex

Guardian, Saturday 2 July 2016

Jack was born with both male and female anatomy, with ovarian and testicular tissue, and genitals that could belong to either a boy or a girl. He has one of at least 40 congenital variations, known collectively as disorders of sexual development (DSD), or intersex traits. It was months before Juliet and her husband, Will, were told Jack’s specific diagnosis, of mixed gonadal dysgenesis. While they waited, all his parents knew was that Jack’s sex couldn’t be determined at birth, and that their doctors needed time to assign it.

Jack’s specific diagnosis is rare, but being born with a blend of female and male characteristics is surprisingly common: worldwide, up to 1.7% of people have intersex traits, roughly the same proportion of the population who have red hair, according to the Office of the United Nations High Commissioner for Human Rights.

Read more here

Suite of five short videos on gender

TestTubePlus, July 2015

TestTube Plus is built for enthusiastic science fans seeking out comprehensive conversations on the geeky topics they love.

  • Every Sex & Gender Term Explained

When discussing hotly debated topics such as gender identity and the like, it pays to be well versed in the language and glossary terms so you can sound like you know what you’re talking about. Let Trace break down some need to know terms for you.

Watch video in post below

  • Science Says There Are More Than Two Genders

Pink for boys and blue for girls right? No? What are societal gender roles anyway and are they good or bad to keep in our everyday lives?

Watch video in post below

  • Animals Care More About Sex Than Gender

There was a study from Yale that found it’s actually really easy for most animals to change sex, and some will change and then change back!

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  • Does Gender Even Matter?

As humans our brains love patterns and gender is one pattern we have established to identify potential mates vs not potential mates. But do we need it?

Watch video in post below

  • What Would A Post-Gender Society Look Like?

We’ve talked a lot about gender this week and its place in society. What would the world look like if gender wasn’t a thing anymore?

Watch video in post below

 

Sex beyond the genitalia: The human brain mosaic

Proceedings of the National Academy of Sciences, November 2015

Significance

Sex/gender differences in the brain are of high social interest because their presence is typically assumed to prove that humans belong to two distinct categories not only in terms of their genitalia, and thus justify differential treatment of males and females. Here we show that, although there are sex/gender differences in brain and behavior, humans and human brains are comprised of unique “mosaics” of features, some more common in females compared with males, some more common in males compared with females, and some common in both females and males. Our results demonstrate that regardless of the cause of observed sex/gender differences in brain and behavior (nature or nurture), human brains cannot be categorized into two distinct classes: male brain/female brain.

Abstract

Whereas a categorical difference in the genitals has always been acknowledged, the question of how far these categories extend into human biology is still not resolved. Documented sex/gender differences in the brain are often taken as support of a sexually dimorphic view of human brains (“female brain” or “male brain”). However, such a distinction would be possible only if sex/gender differences in brain features were highly dimorphic (i.e., little overlap between the forms of these features in males and females) and internally consistent (i.e., a brain has only “male” or only “female” features). Here, analysis of MRIs of more than 1,400 human brains from four datasets reveals extensive overlap between the distributions of females and males for all gray matter, white matter, and connections assessed. Moreover, analyses of internal consistency reveal that brains with features that are consistently at one end of the “maleness-femaleness” continuum are rare. Rather, most brains are comprised of unique “mosaics” of features, some more common in females compared with males, some more common in males compared with females, and some common in both females and males. Our findings are robust across sample, age, type of MRI, and method of analysis. These findings are corroborated by a similar analysis of personality traits, attitudes, interests, and behaviors of more than 5,500 individuals, which reveals that internal consistency is extremely rare. Our study demonstrates that, although there are sex/gender differences in the brain, human brains do not belong to one of two distinct categories: male brain/female brain.

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  • Read a newspaper report of this research here

‘I’m a bisexual homoromantic’: why young people are rejecting old labels

The Guardian, Wed 19th August 2015

A YouGov poll this week put the number of 18- to 24-year-old Brits who identify as entirely heterosexual at 46%, while just 6% would call themselves exclusively gay. Sexuality now falls between the lines: identity is more pliable, and fluidity more acceptable, than ever before.

Read more here