Although most biologists suspect there’s a genetic element to human sexuality, that suspicion poses a serious conundrum: What possible evolutionary advantage would homosexuality carry given that gay people are less likely to have children? In line with Darwin’s theory of evolution, wouldn’t any “gay genes” have died out over successive generations?
To make a long story short, geneticists suspect genes linked to same-sex attraction may be linked to other factors that increase someone’s fitness.
“Fitness” in this sense relates to how likely you are to pass on your genes to successive generations — not necessarily how many squats you can do at the gym.
How about we take this to the next level?
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Now, a new study has attempted to throw some light on the matter. It suggests it’s related to bisexuality.
A new paper published this week in Science Advances, claims that genetic factors linked to bisexuality have traditionally been linked to men who have a greater appetite for risk and have more children.
Risk takers
The research drew upon the UK Biobank, which holds 450,000 genetic samples linked to accompanying behavioral surveys. In short, it has the genetic codes for a large number of gay and bisexual men and women.
Previous research points to a link between genetics and risk-taking behavior in men. This new study goes further, saying there’s a link between risk-taking, bisexual behavior, and an increase in offspring.
How this might influence people who are exclusively gay is unclear. The same study says gay and bisexual people are genetically distinct.
The data shows men who engage in exclusively opposite-sex couplings have the greatest number of children, followed by those who are bisexual and then those who are gay.
However, bisexual men also showed a great appetite for risk-taking and were likely to have more sexual partners. This means they’re more likely to father more than one child, which means their genes persist and do not die out.
Are you following?
“People who carry bisexual genes have more children,” lead author Jianzhi Zhang of the University of Michigan told The Hill. “And the reason they have more children is because the so-called the bisexual genes [mean that they] are willing to take more risks.”
Contraception cuts birth rate
However, that throws up another mystery.
In earlier centuries, having more sexual partners tended to mean fathering more children. Those differences disappeared in the 1960s with the arrival of the contraceptive pill. Having a large number of opposite-sex partners no longer means having more kids.
And yet, we’ve seen a huge increase in people identifying as LGBTQ+ in recent years, with the largest increase in Gen Z.
The authors also acknowledge this. They point to the fact that societal pressure has changed and people now feel more able to be out about who they are.
“We predict that for exclusive same-sex behavior [genetic alleles], they will decline in frequency over time in the future,” Zhang told The Hill. “But because same-sex behavior is influenced more by the environment than by genes, whether the proportion of people in this society will increase or decrease is unknown.”
In a further comment to Queerty, he said, “It is likely that, as society becomes more open to sexual minorities, more people are willing to perform same sex behavior and more people with same sex behavior are willing to come out.”
He added that for the purposes of research, they consider same-sex attraction and same-sex behavior separately.
“We studied same sex behavior rather than attraction. Same sex behavior is influenced more by the environment than by genes, and I believe this is a consensus among biologists. I do not know the situation about same sex attraction.”
The authors add that one of the limitations of their own study is that it drew exclusively on the UK Biobank. This is primarily British people of European ancestry: “Consequently, our results may or may not represent a general pattern across populations with diverse cultural, social, economic, and/or political environments.”
This article was update 01.06.24 to include comment from the study’s co-author.
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Brian
I have a hard time believing this and similar research on sexual orientation when so many people are closeted. There must have been at least some closeted bisexuals in the “heterosexual” group. Those closeted people would mess with the statistics. As long as test subjects are lying, you can’t get good data.
This ends up creating a horrible feedback: LGBT people seem “weird” because they’re unfamiliar, seemingly tiny minorities… and then that encourages more LGBT people to remain quiet… and then that silence leads to less information… and then it perpetuates…
BLAKENOW
As a true bisexual, yes we do exist, I find that the LGBT communities way more judgmental, isolating, completely shut off from understanding that someone can actually genuinely be attracted to both sexes, its ridiculous. So when I’m around my American gay friends, I just stay in the closet about my sex life. because they don’t have a mental capacity to understand it,, whenever I wanna discuss it, they completely change the subject , say EWWW they can’t handle it. It’s kind of hysterical and pathetic at the same time.. My international friends are more accepting, they don’t give a shit.
LifeinShaw
Please. Talk about pathetic. “Bisexuals” are just narcissistic people that want everyone to like them sexually.
Rocinante
No there is not 3,4,5,6 flavors of sexuality. Given there are an infinite number of plots on a bell curve everyone falls on that curve somewhere and possibly in a spot that’s so specialized, there is no one just like them. Of course there are guys, girls or whatever you identify as that slightly like the other or same gender type more than another, then there are extremes on either end. Once there are no societal negatives of any flavor, some form of bi-sexuality will be the mean, in my opinion. Hopefully we will get mature enough that all the labels will end and people will just be comfortable being intimate with whoever they find attractive, sexy or intereresting for a period or maybe just in that time and place. This article is typical ignorant categorization. Very little about human behavior is simple enough to break into a small group of instances.
bachy
@Rocinante: I like your analysis.
Inspector 57
How, exactly, does this study suggest that “bisexuals are helping to keep gay people from going extinct”? Especially since, as the author notes, “The same study says gay and bisexual people are genetically distinct.” In that same paragraph, he basically even disavows the article’s headline: “How this might influence people who are exclusively gay is unclear.”
That mess is largely the doing of the Queerty author. The study’s authors also make giant leaps of bad logic. For example: “‘We predict that for exclusive same-sex behavior [genetic alleles], they will decline in frequency over time in the future,’ Zhang told The Hill.” Ummm… If homosexuality were genetically self-limiting, wouldn’t that predict that the incidence of homosexuality in the human population would have begun dwindling since the onset of homo sapiens? (or since the first appearance of the homosexual gene?)
Sloppy study. Sloppy article.
bachy
There is in fact a genetic basis for same-sex bonding. Dogs have it; they form packs, play with the same sex – and exhibit homosexual behavior. Moose do not have it; they live solitary lives in the forest, and when encountering another male will become enraged and fight to the death.
Humans have it as well; it is integral to the development of things like tribes, friendship, community building, armies, teams – and homosexuality. Same-sex bonding supports survival of the species, and without it human life would not be what it is today.
tonylovesotis
Could it be that the gene/s that express homosexuality in male offspring persist in the population because in female offspring, the same gene/s express fecundity – ie. females that are more likely to give birth to more children? Unproven yet, but time may tell.
FreddieW
Sorry, no. I don’t believe they know enough to say that “gay and bisexual people are genetically distinct”.
Any gay man can have sex with a woman and say he’s bisexual.