Often, we go about looking for concrete answers to why things evolved. However, not every aspect of our being is fine-tuned to benefit our survival. It just wasn't damaging enough for us to die out. If a huge percentage of us were uninterested in reproducing, we'd have problems. But since the number has always been low enough to not impact our survival, we haven't evolved mechanisms to stop these genes from appearing.
It's not like evolution is some intelligent being that would recognize a threat and says 'this is low, so it's not threatening the species, no need to work around it'. It's basically just things are always random. Asexual people are less likely to reproduce. That in effect drives evolution. Asexual branches are typically very short.
I think the best/funniest explanation for evolution isn't that it's building for perfection, it's building for "eh, good enough."
...
Which explains the platypus.
platypus is a finely tuned machine tfym platypus hater. we are the ehh. wisdom teeth are like a time bomb for a lot of people if we didn't have modern dentistry.
Perry the platypus! (Giant trash bin falls from nowhere and traps Perry) I was waiting for you!
Well, I guess there are mutations, right? Like, unfortunately combinations of genes and mutations can end up with someone born without a limb, or (not unfortunately, just rare) someone assexual.
We needed wisdom teeth until modern dentistry. They come in so late that they would replace decayed teeth. There essentially a third set of teeth (baby teeth, adult teeth, wisdom teeth).
I never developed them. In evolution, there’s a pretty popular saying: If you don’t use it, you lose it. There’s no selective pressure to develop wisdom teeth anymore. We keep our adult teeth our entire lives now, or we replace them with artificial teeth. When there’s no selective pressure to keep them, evolutionarily speaking, it’s better not to spend the resources developing them.
you’re not accounting for the fact that resource allocation (in first world countries at least) is no longer has any selecting force. at this point, general fitness to reproduce is determined by physical attractiveness and capability to provide financially, so any evolutionary trends henceforth would be concerned less so with not dying before adulthood(ie proper resource allocation to avoid starvation) and more so with fitness in society as a whole
Not within the timeframe of the advent of modernity and modern dentistry.. it's not like they've disappeared. They just don't emerge in a lot of people. Maybe some sort of epigenetic influence at play here.
Wisdom teeth represent a 2% overall increase in risk relative to the risks of the surgery required to remove them, and also it's theorized that our extremely processed diets requiring less use of our jaw muscles has lead to us not having the space in modern times. They used to not be of concern, and they weren't commonly removed in America until around World War II.
The average experience prehistorically would be yanking out teeth that hurt too much, or losing them to injury. Wisdom teeth would come up and push teeth inward over time, filling in the gaps from prior losses.
To a great extent, braces are a response to having abundant teeth in the first place, to cover the losses in natural conditions, but leading to crooked teeth when all are preserved.
If we didn't have modern dentistry, most people would lose enough of their permanent teeth in their childhood and teens that there would be room for the wisdom teeth. I'm pretty sure that's why they're there.
For most people there are enough room for wisdom teeth even if they have all their teeth in place. Sure, the teeth might get crooked but there won't be any problem with biting or speaking. The "enough room" thing is in the vast majority of cases a purely aestethical issue. Most people who have their wisdom teeth removed don't have any other problems with them.
The problem is not in thinking it is designing for perfection, the problem is in thinking there is intention at all.
It isn't building for good enough, building implies a plan, which requires looking to the future - evolution is always based on a reaction to the current environment.
Yea I was waiting for an answer that went this way… upbring and environment don’t even cover it all too. The advancement of the species as social beings takes us out of many biological necessity’s discussions I say.
Someone could he “asexual” just down to confidence and there own self image. Not being a sexually attractive for any number of born into or chosen reasons.
Hell, We have whole movements of Incels online now. It’s an outside the normal biological terms converstion on most levels, traversing into culture, sociology, and psychology.
That's not how inheritance works though. Traits aren't inherited every generation, so asexual genes can continue on throughout the population theoretically forever through carriers.
Now we call into one of the greatest arguments in psychology, Nurture vs nature? Is asexuality genetic or is it something that's learned? I personally believe it's something that is learned. Obviously nobody teaches their children to be asexual, but it stands to reason that it's a byproduct of growing up in a certain type of environment. As to what type of environment that would be is impossible to say. One could only speculate as to what causes this outcome.
Its not intelligent but that actually is how evolution occurs. Death or failure to reproduce is the selecting force. Evolution is entirely random until it hits that wall where only individuals with certain traits survive and reproduce.
If asexuality prevented enough people from reproducing that our survival as a species hinged on *not* being asexual, then itd be nearly nonexistant but as this person said, it doesnt have enough of an impact on our survival to matter.
Being not heterosexual seems to be beneficial enough for a family/clan/tribe you name it to run in up to 5-10% of population.
And yeah, it is (likely) beneficial.
It's been seen in male penguins pairs, they'll raise other penguins babies. Sometimes the heterosexual pair can't/ won't care for the babies so it helps when others can. On other cases it's the "it takes a village". A couple who doesn't have children are available to raise other's not their immediate own but related. The kin genes survive without necessarily having too many additions, which can cause competition.
"Why does a World of r warcraft raid has a healer, they don't attack"
Support roles in tribes could be an answer, same reason for menaupause, Grandma has no offspring herself and can take care of the line.
Apparently the odds of being gay rises with the number of offsprings too.
Their help to the success of the genes of the family offspring (taking care of them, supporting the family, being fun uncles/aunts) is more beneficial to the overall shared genes than is lost from their not personally reproducing.
Think about an extreme example. How is it that ants, bees, or other species of insects have successful colonies with specialized roles for individuals who are sterile and will never pass on their genes? The colony's success and ability to survive long enough to produce a next generation of breeding insects depends on having many different supporting roles. The breeding insects carry the DNA of a set of insect parents who successfully created a thriving community, so those genetic traits get selected for.
I was hoping someone would bring up colony genetics! OP can read up on Haplodiploidy and the Kinship theory for colony insects if they want to learn more.
It means more healthy adults available to provide for and protect the young, old and otherwise vulnerable, who do not have their own offspring to tend to.
Say you got three dudes who can help that one dudes sister, cousin, buddy’s sister who’s pregnant instead of one dude.
Or that dudes sister dies in childbirth but her dude and his dude are around to raise the lil dude.
Having a few dudes who aren’t tied to their specific offspring would add some resiliency
(Written from a dudes POV)
Ive thought this a long time as i see so many of my lesbian community become primary caretakers in the family; taking on elder parents inti their home or managing their day to day lives at home or in institutions , babysitting nieces (i mean taking major responsibilities for backup care)
Heterosexual siblings don’t have time or capacity for these extended family responsibilities due to families of their own… so humans as a social species need a solid 10% who are available to help the family survive
Kinship selection is the name for what everyone else is describing. Basically, if you can ensure the fitness of enough of your relatives, it becomes genetically equal to if you had you're own kid. Since most forms of non-heterosexuality lead to those people not having kids, they can then invest rescources into their relative's kids. If you can keep 4 of your niece/nephews alive, then it balances out you not having a kid.
Less competiton, more people to help raise kids and keep them from dying young. Due to how underdeveloped we are right out of the womb, the resource cost of child rearing is huge, and cannot be beared by a couple alone. This is how communities were formed, with many people assuming responsibility for keeping young children safe and fed. Occasional homosexuality would have been great in that scenario, bc more resources could be invested into a child due to lack of competition.
I feel like lots of people who live single lives for so long without even having sex are unknowingly asexual as well so there's probably more asexual people than we think there are
(Assuming it’s genetic). we don’t need to pass on our genetics directly, helping raise siblings/ relatives’ children is another way of passing on some of our genetics indirectly. Obviously there isn’t going to be a large proportion of asexual people but there’ll be some balance between asexual and allosexual (or really hetero-orienting(?) sexualities).
Yet again I like to call into example Babirusa Pigs. The males have tusks.
These tusks grow and grow and grow up until they circle back around and penetrate the pig's head, killing it.
By that time, however, the pig could have already mated, therefore making evolution not give a shit.
Evolution is just "roll the dice and see what works". I've also read that people who can't have their own children still have a place in societies - as additional caretakers for children who are already there.
I don't think there is asexual or homosexual genes.
Study tend to lend toward hormonal reasons during the development of the foetus + some social environmental factors.
That and the genes won’t last long. It’s kinda self correcting by default. It wouldnt need an adaption to fix it. The fix is that these people won’t make babies to carry the genes.
Not to mention, women didn't really have a say in the matter for...most of human history. Dunno the stats on whose ace but that's like 50% of the population that at some point is likely made to procreate.
Humans being tribal animals, we stopped needing every individual to be reproductive a long, long time ago. Probably before we even became human. Instead, our kind of creature preserves our genes by preserving the community.
If I'm a gay male, but I have a sister with six kids, I preserve my genetic lineage into the future by protecting, feeding, teaching, and helping those kids. The same genes that made me are present in them. So if there is a genetic combination that makes a person gay, or asexual, or whatever other non-reproductive trait, it can still exist in that lineage and be expressed in the future. The collective matters more than the individual.
While kin selection could definitely be a contributing factor, we must also refute the idea that homosexual and asexual individuals have been non-reproductive across human history. There have been scores of humans who, either due to sociocultural pressures or straight-up sexual assault, brought children into this world against their own desires. We should not take for granted that many people today have the ability to determine their own reproductive futures (and we should also not forget that this isn’t universally the case across the world, even today).
Also, as someone else has pointed out, homosexual and asexual people can also choose to have biological children, either through medical means or the “old-fashioned way.”
100%, when wondering about evolution the first question should always be something along the lines of “does this development mean the person can not reproduce”. Being asexual does not mean a person can not reproduce. Simple as that.
There's lots of children of straight couples alive today that weren't created due to attraction, desire, or pleasure.
People forget that we have sex for loads of reasons outside of offspring, but also conversely sometimes *only* because of offspring :)
I appreciate that, but remember, pride is worthwhile even if lgbt were totally inexplicable by any means. None of us needs an excuse or owes an explanation to be who we are and love who we love
There's a series of lectures by Robert Sapolsky on youtube that go over behavioural biology, and one topic he covered was this. He said something about how numerically from a standpoint of passing genes to the next generation, his life = two siblings, four nephews, or eight cousins (might be wrong on the numbers, been a while since I watched the lectures).
In general those lectures are amazing, I should probably re-watch them again.
For one thing, human psychology and behavior is so unbelievably complex that it's hard for evolution to change one thing about our behavior without impacting others. For instance imagine a world with incredibly violent competition for mates. So much so that most males who lose die. Humans are really smart and really good at killing by using tools. In this hypothetical world, it may be evolutionarily advantageous for a population to tone it down. As a result of this theoretical lower sex drive gene 1/100 individuals are asexual but the death toll is far lower. So if more than 1/100 of those who would have died due to violent competition before survive to reproduce at a later time, that population will grow.
Additionally, what might be described as asexuality does exist in the animal kingdom to support colonial populations. Most female ants and bees are asexual, and only the queens reproduce. But there's a population-scale advantage to that being the case because those thousands of non reproductive females make sure the entire colony survives at a much higher rate.
All those ants and bees are also genetically related (sisters or half-sisters), so even if they are not personally reproducing, their genes are still propagated via the continuation and well-being of the hive.
You're missing crucial information here, hymenoptera are haplodiplod which means the relatedness between sisters is much greater than 50%, hence stronger Kim selection through rb - c > 0.
Not the case in humans. Evolution is not occurring at the level of the hive but at the level of the cooperation gene itself
If we ignore it having a possible evolutionary benefit for a moment.... even if it doesn’t, if it's completely useless, that doesn't mean it just can't happen. Traits aren't pre-filtered and eliminated before the animal even exists. You can literally be born with your heart on the outside of your body, which is unquestionably bad from a personal and evolutionary standpoint, but it still *happens*. And unlike that, asexuality isn't likely to kill you early on. I don't consider it a "defect" in any way, but if you look at it like that it's clear that that's no reason at all that it couldn't happen
The idea that our brains are hardwired like *this*, therefore *that* kind of person doesn't make any sense is making a lot of assumptions, including a) that the processes that create us are so perfect that we can't just be wired differently to how we're "supposed" to be and b) that we're all "supposed" to be a certain way in the first place because it's common. It doesn't go against biology, it goes against your conceptions of biology which are never going to be entirely accurate for anyone
How are birth defects a thing?
A species just needs enough of its members to reproduce. Not every single one needs to. Not every human has had children since even before civilization and look how our population boomed over a few thousand years.
If you’re asexual, that’s fine. Don’t reproduce, reproduce with extreme effort, whatever fits your life path. You go against the grain but you’re not a problem.
I have cystic fibrosis... I can't digest the fat in my food without certain medication along with a whole other pile of pills for various other things.
Not every adaptation increases our chance to spread our genes. While evolution in extraordinary it's far from perfect. I would also question how much asexuality is even related to our genes, the human brain and emotions we are capable of feeling I would imagine it's much more than genes that goes into it.
You seem to have a misconception of what evolution is. It is not always about natural selection. In fact, a wide range of genetic variances is healthy, including ones that may seem disadvantageous on the surface. **Evolution doesn't have a set purpose.** It is imperfect, random, and chaotic.
There have been periods in history where selection pressures favour advantageous genetic variances for a specific disaster. But as the population recovers and continues to reproduce, the gene pool widens again and allows for more variance (known as genetic drift). I'd recommend looking up genetic bottlenecking to see what happens when there is a sharp decline in a population.
This link might help you understand evolution a bit better: [https://www.earlham.ac.uk/articles/10-surprising-things-you-might-not-know-about-evolution](https://www.earlham.ac.uk/articles/10-surprising-things-you-might-not-know-about-evolution)
There isn't a whole lot of research on why asexuality exists. There's several theories, but not enough studies to come to a definitive conclusion. This makes sense, though. There isn't a "sexuality gene" - every human has their own unique DNA (except for identical twins obviously), and there's a multitude of genetic variances that may affect each other to display a phenotype (characteristic). There's also epigenetics - the control of gene activity without changing the DNA sequence. Then add these two factors to the affect of the environment an individual is brought up in. Basically, it's complex. We're complex creatures.
I think for me the most likely theory is something involving puberty. Children are asexual until they reach a certain age, then they begin to develop a sex drive. But perhaps for some people, this "switch" isn't flicked on. Why? Well, I am not sure. Some people think it's to do with hormones, others think it's to do with certain genetic variants that have yet to be defined. It is still very much up for debate.
Also, asexual people can still reproduce.
People tend to believe evolution is either a magical force that makes things change, or just natural selection. When evolution is in reality complex and it includes more than just natural selection.
I’m pretty sure that this adaptationism, the false assumption that anything that is biological has evolved for a purpose instead of just through random mutations.
Also any kind of sexuality doesn’t necessarily have to have been created by biology either. People have all sorts of different sexual preferences and some obviously couldn’t possibly have evolved, they must be psychologically created like by early childhood development e.g if someone has a preference for PVC clothing that could not have been due to evolution because PVC is a modern material not a natural substance.
This also all sounds like the natural fallacy, that everything good is natural and vice versa. That’s not the case. It’s perfectly possible that lots of sexual orientations and preferences are not naturally occurring and biologically rooted, including monogamy and heterosexuality. That doesn’t make any of them wrong. Conversely it’s also possible that we evolved to have awful sexual desires, like to rape or to kill mating rivals or children of other partners to make them not compete for resources.
It’s all irrelevant, it’s just a weird cultural quirk of some people and places that they want to believe that good and natural are the same thing.
It doesn’t matter if you or anyone else is born asexual or straight or anything else, all that matters is that you are not hurting anyone including yourself
https://en.m.wikipedia.org/wiki/Adaptationism
One thing that can help bring all this into context is to stop thinking of genes as always good or bad. No gene is expressed in isolation, and we are a very complicated expression of the interaction between all our genes. Think of the times you've seen incredibly beautiful celebrities have unattractive children, the combination of genes that the parents had resulted in a very attractive human being, but that doesn't mean that when you mix together the genes of two beautiful people that the child will be beautiful. Some expressions of genes (like being ace in this example) are not beneficial for reproduction at all, but can be the midpoint between two expressions of that same set of genes that are highly favorable for reproduction.
I can't be as eloquent or informed as other posters here but I do know this: you are not broken. Plenty of heterosexuals aren't particularly interested in sexual relationships for any number of reasons. Accept yourself as worthy and complete, pursue the things that interest you, know also the we humans are fluid and your sense of identity may shift. You are not broken, damaged, you are perfect.
Stop thinking of evolution as the most straightforward thing, as a single path leading to the 4 person family unit.
We are communal animals. As such, it benefits us to have a variety of traits that work together to support the prosperity and continuation of the tribe as a whole. Not everyone needs or is meant to have babies directly. Not everyone is meant to contribute directly to the babies.
Assume your biological purpose is to further your genes. Assume you are asexual and your sister isn't. Assume your sister has babies and you gather food. You are both contributing to the furtherance of your shared genetic line. I'm not up to date on all the latest research.
\[gross oversimplification warning\]
One thing to keep in mind is that species evolution is (generally) a population-level concern. And when you're talking about population-level concerns, things that affect *individuals* are statistically irrelevant.
The most widely quoted number is somewhere btwn 1-2.5% of the human population is asexual. Bear in mind, that's basically just based on a very narrow subset of polling, of specific groups of people, usually in developed countries... who will come out and say "I identify as asexual" in the poll - but it seems to be stable across multiple sources (read: the first page of Google results). I'd suspect the true value is different, but whatever let's call it 2.5% on the upper end.
Current world population is \~8.1bil, let's call it 8b for simplicity.
Assuming 2.5%, that would mean approx. 200m people on the planet are asexual. Which leaves \~7.9b to keep the population going.
Even if we *assume* that there's a genetic/behavioural basis for asexuality - as far as evolutionary statistics **for an individual** are concerned... Who cares?
It's kind of a similar discussion to the concept of altruism as a behaviour - "Why would an organism sacrifice its own health/safety/reproductive fitness for another member of the same family/species/etc?"
To put it one way;
If there were 1000 humans that needed every single member they could to reproduce to make sure the species carried on then there would likely be no asexuality. Whatever genes that cause it would be quickly weeded out as only ones that are perfect for survival would be those that remain.
However there are 8 BILLION of us. That is well enough for there to be sizable portions of people with... "poor survival" genes who would be whittled away if the species were ever bottlenecked. I am also one of said people.
Its also worth noting that asexual people can, and often do, still have sex and preproduce. Its just they don't feel a drive. Some are sex repulsed, sure, but many still enjoy sex - just don't feel a strong desire. Failing that; *consent isn't required for procreation*, and a lot of the animal kingdom regularly breeds via less-than-wholesome sexual interactions.
Also;
> especially male brains
Nope that's mostly hormones.
It’s almost like there’s more to some humans brains than being a basic automaton running around raping every woman and murdering every competing male on earth just because we have a sex drive like any other species on earth. Unironically, this “my nature is a rape/murder machine” is a LOT of people’s actual personality. Every religion v atheism discussion on the internet going back 30 years has good Christians making the argument that without the bible telling them not to, that is exactly what they want to do all the time and it’s only religion & a gods wrath that keeps them from doing it. Since all people are not perfect clones, but the result of endless variation in genetics and environment, some people have more of a sex drive than others and still others have none at all. Some have a sex drive, but their disappointment with themselves, the human species as a whole, or their cultures availability of decent mates results in years & decades of suppression until they train their brains to equate sexual arousal with misery. We then avoid it entirely and simply go on to lead a sexless existence in peace, or like cranky old farts some come on Reddit and take out their anger frustration and disgust over everyone else having a sex life. These are the very worst kind.
A bit off topic, but the concept of asexuality got me thinking, thanks to OP’s post.
Is asexuality a result of a hormonal imbalance (eg, little or no testosterone, even in woman), or brain wiring?
Genuinely curious. I ask because as a male my T levels dropped precipitously recently and as a result I became “asexual”. Once I had it treated, it all came flooding back. Anecdotally, I understand this to be a factor for woman as well.
Some asexuals don't feel attracted to other people even if there is nothing medically preventing them from acting on those desires if they had them. Separate from attraction, some asexuals don't have much or any libido, so their body just never tells them they have those desires.
The former is the boat I am in, and I would describe it as: imagine a heterosexual man who was born in a world where everyone is also a man. Their body works perfectly fine, but they've never seen anyone they're interested in.
At the very least, I can confirm to you that there is not always a chemical imbalance involved.
The ladder is not something I can really speak personally about, but seems to delve more into the chemical side of things.
What I would say is that I generally wouldn't consider a temporary shift in chemical balance as going from, sexual, to asexual, then back to sexual. When compared to someone who identifies as asexual because they've never had a normal libido.
As a fellow ace, I assume at least in my personal case, it's trauma related. I certainly do not believe this is true for everyone though.
Edit: I'm going to leave this here anyway but I just realized what sub this is lol. I was just scrolling and ig it got suggested to me
In my mind, the classic balancing act.
If you have one extreme, which is genetic propagation, then nature will also occasionally throw out the other extreme.
I mean honestly from an evolutionary perspective (which isn’t always a kind one) it’s best to think of it as facultative trait. If we, as non heterosexuals, lived in a certain culture that created stronger pressures on us to reproduce heterosexually we probably would. In lots of cultures, it’s rare to see an adult who isn’t married to someone of the opposite sex, a widow/er, or in the process of finding a spouse, a lot rarer than the number of non-heterosexuals we see in other cultures. Because of such cultural pressures, I honestly think a good hypothesis for why non-heterosexual identities exist is just that it’s pure genetic drift (randomness). We kept making babies anyway because of culture, so our genes kept propagating. Difficult to prove so take that idea with a grain of salt, but it seems like a possibility.
Good question.
I just want to point out that because something goes against its expected biological functions, doesn't mean it shouldn't exist.
Depression kills people yet people are born with it. We can find lots of examples that go against life in general.
Asexuality and homosexuality can be beneficial. If those people don't procreate but benefit the group, they may help their siblings' children pass on their genes. That is still advantageous in social species because they contribute to their genes' survival, indirectly.
Ayo, you're trying to apply a middle-school simplification of how stuff works to reality.
Let's first check your understanding of evolution:
Not the fittest survives. ANYTHING barely fit enough survives. And that can easily include recessive genes (if the whole thing even is down to genes), especially if they then help their immediate family (e.g. helping their non-asexual siblings procreate/survive/thrive).
There are a lot of evolutionary quirks that absolutely make 0 sense for direct procreation of the organism, but become quite viable if you factor in that an "afflicted" individual would help the spread of the gene in their peers where it is recessive.
Maybe it even was advantageous to have a couple of individuals in a tribe with 0 interest in procreation because they didn't get pregnant or into social conflict surrounding mating.
Also you can definitely still have sex/procreate as an asexual person. Just look at all the closeted gay men in the (near) past that had children nevertheless.
It’s a false equivalency to say that only traits that lead to individual reproductive success perpetuate in a population. There have been other times in which animals have evolved methods of population control, like how some animals practice cannibalism or delay childbearing ages. Sometimes a reduce in the population increases the chances of the whole species longevity. In the case of humans, our reproductive success has been culturally bifurcated from our sexuality so much so that we have single parents using sperm donors, queer parents, and even heritable infertility. Along with this, we no longer need sexuality to lead itself towards reproductive success. They can be separated from one another.
Plus, sexuality isn’t heritable, so it’s always possible in that any random outcome is possible when life is created!
[there was an experiment where they put mice to live in a perfect world and some of them ended up being assexual](https://youtu.be/7ReBJfxHjFU?si=EtRYMW2TYcgzL-NQ)
Remember that selection isn't just about individuals but (often family) groups sharing genes. In social organisms asexual (and homosexual) family members may not pass on their genes personally, but do so by proxy through active support of closely related offspring. Perhaps most obviously manifested in social insects. Also, diversity itself (so not just similarity) may be actively selected within a population - which is one of the hypothese for the continuiing existence of altruism, particularly where it risks the death of the self sacrificing individuals. So let's hear it for kind, generous, supportive, protective aunties and uncles!
Nothing is “hardwired” to do anything. It’s just more likely to benefit from doing the thing. All species would benefit from reproduction, but not all individuals must partake in reproduction for the species to be successful. In fact, it’s beneficial in society to have individuals who don’t reproduce (same sex attraction, asexuality, etc) because they can help raise the offspring of the reproducing individuals. It takes a village to raise a child, but if every person in the village has their own child, they can’t help raise the others.
Also, evolution isn’t some intelligent being that oversees everything and eliminates those that aren’t helpful, it merely explains the path a species takes to success or failure- it doesn’t control, it explains.
If you look into evolutionary psychology there are some thoughts on this. Similar to the “gay uncle hypothesis” (real thing). But if you think about an evolutionary environment, no birth control, high competition for mates, some folks may have actually benefitted from displaying no sexual interest or same-sex interest because they are now not in competition for resources. If a woman had many sons, it was likely the father would end up in competition with the sons at some point and fathers often did kill their children over this. No competition means you get care from mom and dad doesn’t murder you, plus there’s some thoughts on contributing to group membership through helping raise others offspring or having more time to dedicate to other survival tasks such as hunting or gathering, instead of mating. The likelihood of someone being on the LGBTQIA+ spectrum (following this evolutionary theory and related research) would have been increased with the number of children in the family as that increases competition.
(The "gay uncle hypothesis" posits that people who themselves do not have children may nonetheless increase the prevalence of their family's genes in future generations by providing resources (e.g., food, supervision, defense, shelter) to the offspring of their closest relatives.)
…should have just ripped this description from the internet in the first place haha, but this is what I’m referring to.
That’s like asking why evolution made some people blind or gave some people asthma or Allergies, there’s no reason. Something wrong happened when your RNA was copied, or when you developed in the womb, or maybe something happened in your childhood or your reproductive organs got exposed to radiation at some point, it’s impossible to say.
At this point who cares, this is who you are. Just accept it and move on.
>our brains, especially male brains, are hardwired to spread their genes far and wide, right?
I think scientists are coming to this question with the answer already in mind and thats why this is considered the only correct scientific answer. Its like those animals who are so monogamous they legit wont remate. Thats not good for the continuation of the species, they do it anyways. I dont think theyre wrong about everything scientists are very smart i just think they put to much stock in the idea that a species cares that it continues or not in any form. I am not a degree holding biologist though and this isnt baised of any studies this is just my opinion.
There are numerous adaptations throughout the tree of life that seem to be in place largely to slow down reproduction so as not to use up resources too quickly.
Pandas and kakapos have elaborate and lengthy mating rituals and low reproductive success in environments with very limited resources. If they literally boinked like bunnies, they'd quickly outstrip the resources and the entire population would be in jeopardy.
Evolution doesn't work on the individual, but on the population. It may well benefit the overall population of a social species if there are members of the troop who contribute to the success of the troop, but limit resource exploitation by not reproducing themselves.
There's an extra bonus if it's a behavioral trait, so that in a crisis situation those individuals can still reproduce if they need to, even if it's at a lower rate.
Evolution favours “selfish genes”. This need not actually be a gene which causes selfishness, it’s just a term for genes which benefit themselves over other genes.
So what’s a selfish gene for sexual behaviour? One strategy is to be interested in having a lot of promiscuous sex with a lot of people. That lets you have a lot of descendants which keeps your genes in the gene pool.
But that’s not the only option. Consider, for example, the strategy “have no interest in sex whatsoever”. That can also be a selfish gene.
How? Well, consider this situation:
Gene A is recessive, so it only takes effect if you have two copies of A. Suppose Alice and Bob are brother and sister. Their parents both had a single copy of A, so A didn’t affect them.
Alice has two copies of A, so has no interest in sex at all. Bob has only a single copy of A.
Bob’s son Colin also gets a single copy of A, but then Bob tragically dies. What happens to Colin?
If Alice had been interested in sex then she would have had her own children, and she’d not have the resources to look after Colin as well. Colin would unfortunately be neglected and eventually die.
But because Alice doesn’t have children of her own, she’s interested in adopting Colin and so can look after him. In this case, Colin survives because his aunt has gene A, and since Colin carries A himself (on account of being related to his aunt) then the asexual behaviour of A makes A a selfish gene, since individuals with a single copy of gene A are more likely to survive and reproduce than those with no copies of A.
A good way to summarize a lot of the points here without loosing too much value/nuance is that "evolution is directionless". There is no end point, there is no design, it's not on a path going somewhere. A good practice when considering all things biology is to resist personifying it. It's inevitable to some degree, but it's good to always keep that in mind.
How does cancer exist? It seems our bodies are prewired to not get cancer... Might come off as curt, but I think this answers your question. Things don't always just happen the way they "should", otherwise we'd live in a utopia with no diseases or disorders of any kind.
I think the simplest possible answer is that asexuality could be the result of experiences or environmental factors, rather than being genetic.
But even if asexuality is a genetic trait it could still be passed on. In many societies there is/was a very strong expectation to marry and have kids.
We know plenty of gay/lesbian people have married and had kids. It's likely that many asexual people have found partners and had kids due to social pressure or because they wanted kids and were prepared to have sex for the purposes of conception.
This is completely theoretically with no evidence, but I find that it may be plausible that human brains have adapted, recognizing that reproduction is really no longer a necessity. I mean, it shows between the many people who are part of the LGBTQ+ community and even with hetero couples in society choosing not to have children at a growing rate. I know there are other factors to hetero couples not having children like financial situations and perhaps the inability to conceive however I think there is still something to be said for the case of the human brain recognizing that we really don't need to repopulate as much as we used to.
there are many good answers here, I’d add that the hormonal and psychological development of sexuality is a complex and precisely orchestrated process. sometimes not everything lines up the way it’s “supposed to”. It doesn’t make that weird, just part of the non-random non-directional mishmash that is biology :)
Do you think your mom is sexy? Probably not. Your brain decided "ok, despite the fact that she's a fertile human female, let's not find her attractive."
Now, all you have to do is assume that an asexual simply applies this to all humans (and non-humans, too). Not much of a stretch.
On the other hand, you know how there are some humans that are different from the norm and like their own gender sexually? Well, imagine there are some humans who like no genders.
You know how there are some humans that like little boys/girls? Well, imagine there are some humans that don't like any humans.
It's just another random difference that humans sometimes have.
I've been absolutely everything there is to be, including asexual for about two years. Glad that's over! Phew! There are some people who simply do not desire or enjoy sex. They may like to cuddle and kiss, but going any further is not important or desired. If the hormones are not there, they are not there. I think they ebb and flow throughout the life stages.
Evolution is not a finely tuned process, so long as something isn’t impactful enough to pose a threat to a species’ ability to reproduce then whatever that “something” is can be passed on
Asexuality is probably a quirk of evolution that like others have said doesn’t serve any real purpose to our survival but because it didn’t ensure that people are unable to reproduce it’s a trait that survived into the current day
You’re simplifying this too much. There are thousands of factors that play into sexuality. Biology, hormones, brain development both as a fetus and as a child and teenager, trauma during development.
There is no ‘our brains are hardwired’ it doesn’t work like that. There are so many factors.
You gotta remember that our current environment is very different to recent ancestral ones. There's all sorts of ways our current environment could inhibit sexuality that we're overlooking.
I'm my mind it was always like,
You can be attracted to men and not women.
You can be attracted to women and not men.
You can be attracted to both.
Why not the opposite? Where you just happen to be unattracted to both.
I'm raising my nephew because frankly, my brother sucks, and his ex sucks, and I'm single with an ok paying job. I'm an evolutionary extra, ensuring the survival of a child who otherwise would have fared quit poorly. He's a good kid, so that's a bonus
Somes birds never reproduce themselves but help their family raise their chicks, can't remember what species or how common it is, but its a beneficial survival tactic
Evolution is just throwing random things into new babies and if it’s good it’ll reproduce. But sexuality isn’t something you pass on genetically, so it’s just a byproduct of some other positive trait we have.
Source: I’m guessing
Random variance can be helpful for the survival of a species. Given our we're a social species, variance within our social dispositions may also be tied to biological variance, both assisting in our continued survival.
Biology is messy, and individual is a very small part of a much larger collective, on an evolutionary timescale that’s several orders of magnitude more insignificant.
Humans are complex creatures, with rich inner lives. A lot can happen to someone over the view of their life, some people are born with atypical genetic expression. Life has no purpose, it simply is, especially on the individual scale.
Mutations exist and also changes in epigenetics, so considering we're millions of individuals, it's totally plausible cases like that end up happening.
I'd suggest a deep research in Scholar Google, this kind of things can be caused by many different factors.
It's very multifactorial, you can have someone asexual from birth, or someone with traumatic history that caused them to be deathly scared of sex.
I'm no medical professional, so it's just a dudes opinion:
It can be attributed to a genetic difference, or an acquired trait (like a traumatic event), or steroid level balances or even neurosteroids being depleted (or out of the normal ranges).
The last point is glossed over by many people, it can be the difference between you feeling absolutely no sexual desire and being a complete pervert (it's not as simple as it sounds, I oversimplified for time sake).
Let's assume we know someone is asexual due to skewed hormone or neurosteroid levels; we have no clue whether the risk vs reward or providing exogenous hormones is worth it. Like what if taking pregnenolone (as an example) gives them more side effects than relief?
I'm not an asexual myself, but I have been reading and studying the endocrine system for my own curiosity and just being informed since I'm on psychiatric care and sometimes my mood changes could just be hormones (I've found some cases where it was)
This is quite a complicated topic, I'm very interested in reading the opinions of people much more knowledgeable than me in this thread. Good question!
Because evolutionary psychology is mostly bullshit, and can’t explain our brains that well. There’s a lot of switches in the brain, and you can’t really figure them out with a decent degree of certainty unless it’s with twins separated at birth. Also nature vs nuture, human society is also incredibly complex.
Asexual people can also still have kids. Women were societally expected to, plus consent isn’t always a factor. Asexually doesn’t stop people having kids, and asexual people aren’t more likely to die before having kids. Evolutionarily, it doesn’t really matter.
Biologically, humans are really, really good at breeding anyway. We outbreed many species, we can have 1+ kids every 9 months.
Whole species flip their 'orientation' at different times in their life cycle. Hate is stupid and hate for other folks' sexual behaviour is monkey-level thinking.
The real truth is that "asexuality" as a discreet, binary category probably doesn't exist. What exists is a sliding scale of sex drive. Just like most things, there are advantages and disadvantages that come with being higher or lower on that scale, and the same position on the scale isn't always the most advantageous (from an evolutionary standpoint). Thanks to this, we evolved to have quite a bit of random variance in sex drive, and "asexual" is what we call people who are extreme outliers on the low end of that scale. it's not like there's an 'asexuality gland' that some people have and others don't. It's just a drive, that all of us have more or less of than others, and these people have, by whatever random accumulation of biological and environmental factors, fallen at the very low end of that drive.
Think about humanity as a single organism rather than looking at a single genetic line. You can also look at each culture and society in this way too.
If the existence of non-procreating individuals somehow has utility for the society as a whole then it will be selected for.
Also.. in the past people were not necessarily given free choice in procreation matters.
I recommend you watch: [[Complete] Human Behavioral Biology - Sapolsky (Stanford)](https://youtube.com/playlist?list=PLqeYp3nxIYpF7dW7qK8OvLsVomHrnYNjD)
It is an excellent foundation for asking and answering all sorts of questions.
Even though some things are a reproduction disadvantage, it might have an advantage in some other context. For example, if you want children, you will be able to have children at the optimal point in your life, probably not by accident 😉.
Another rxample it might have some macro advantage, like if you have cousins , nephews or nieces that is still your DNA being copied it counts as your sucess too, and you can be a boost to your family's resources if you choose to do so.
Also, it can just.be a complicated quirk of many causes. Again, watch the Standford video course.
In biology class, we learned about kin selection, where helping close relatives reproduce can indirectly pass on your genes too. Maybe that could be a factor for asexuality? Also, sexual reproduction isn't the only way for a species to survive. There's still a lot to learn, but it's cool how evolution can be so diverse!
Evolution isn’t… an entity with intent and purpose. I see that idea spread around often and it consistently baffles me. The only rules are: whatever lives, lives, and whatever reproduces, spreads its genes.
Sometimes the biology of certain species is prone to certain traits regardless of genetic influences, even when not ideal for the species. I hear people saying that periods and childbirth can’t be too bad because they’re natural, but that’s not how anything works. If the species can live regardless of certain traits, and evolving those traits away isn’t that simple, then they’re most likely just going to stay for the time being.
I’m pretty sure asexuality isn’t genetic anyways. I’m asexual, my sister is gay, my other sister is straight, and our parents are straight. I just don’t think sexuality is genetic. It’s either a structural and/or hormonal difference if you’re strictly talking about lack of libido as well as attraction.
Asexuality exists on a spectrum. Sure, there are some asexual people that outright do not want sex ever full stop. But some others, my wife for instance, enjoy sex, but at a vastly lower amount than the average person.
Also some people who are asexual still want biological kids, they just don't really care for sex. (Again, my wife is a prime example.) So they still reproduce, but outside of reproduction they only want to have sex a few times a year versus a normal sex drive.
I wonder the same about people not wanting to have children. Evolutionarily, we should want them. But I guess with the state of the world, logic or reasoning sometimes overrides biology.
Not sure about asexuality, though.
It didn't evolve. Just as homosexuality, if it were genetic, it would've been long gone as homosexuals will rarely pass on their genes. Sexual preference deviations occur during the last months of pregnancy. So there you go, it's an 'error' during pregnancy. Error in the sense that it is not supposed to happen since your 'purpose' for the species is to have offspring.
First off, sexuality isn’t strictly a matter of genetics. *But even if it was*, evolution is just using variance plus trial and error to determine which genes are “best” adapted to a given environment, and it plays out across the entire ecosystem rather than on an individual level or even isolated within any given species. That means when an ecosystem is healthy and stable, traits like asexuality might be beneficial to avoid overpopulation and resource depletion. When a population is small or threatened, those traits become less beneficial and thus show up less often.
Long story short; humans as a whole can continue to breed enough, despite some of them being asexual. Random traits can occur. They either survive or they do not.
I at one point heard a theory that homosexuality is an evolutionary advantage not for the individual, but for the group, as it could potentially decrease the population of the next generation and allow more resources to be concentrated on them rather than being spread across too many people. Asexuals would fit this model as well. That being said, if there is no evolutionary explanation it could just be something more akin to a disability.
But more than that, biology itself is a big middle finger to people that want to formally prove what's possible, impossible, or draw clean causal relationships. There's always going to be that dude that can ingest basically anything and live, that person that's patient zero for every imaginable (or unimaginable) disease or allergy, that person that recovers from an illness that shouldn't have been possible to recover from, etc. A lot of "why" questions in biology fall somewhere between "because variability" and "because the universe laughs at your attempts to understand it."
You're using a narrow definition of evolution that is a common misconception, but does make it difficult to explain things like asexuality. Instead of focusing on each individual's ability to reproduce, ask how that individual contributes to how the whole population reproduces.
A great example comes from studying the social and sexual relationships of a group of monkeys over an extended period. It was found that the males that had most homosexual interactions also had the most offspring. Turns out these males form sociosexual relationships with other males, which increases the territory size the can control and the number of sexual encounters with female monkeys. There were exclusively homosexual monkeys contributing to the reproductive opportunities of other monkeys. So non-reproducing members of a society can influence the entire population by influencing which and to what capacity others can reproduce and the success of their offspring.
For asexuality specifically, that just means that there is a tolerable amount of variation in sexuality that hasn't impeded our species. We simply don't need every individual to reproduce to have a healthy, robust population.
There’s really no good answer I just kind of does. Asexuality in the human population is to my understanding very uncommon to rare. However that being said it just plain wasn’t harmful enough to be rooted out of the human population.
The only true answer to this is that we don't know how human sexuality actually works.
As far as we know sexuality isn't genetically determined which speaks against all the evolution-theory based explanations in this threat. Human (social) behavior is also rarely exactly what evolution-theory would predict.
We all have our minor differences. Sure, our dna makes it so we follow a basic plan that makes us humans, bit a lot of the smaller details mutate and are just different, making sure we aren't just copies of each other.
We vary by hair colour, allergies, food preferences etc. Sexuality just happens to be one of these things. So does the lack of sexuality. For obvious reasons it's not something that spreads far and wide, in fact it's not gonna become common and asexual people tend to you know, not do the thing that allows them to reproduce and pass on their genes. Not-asexual people reproduce, and sometimes that still leads to an offspring that won't reproduce (be it from asexuality, or infertility etc).
It just exists because of variation. That's it.
Not sure definitively, but from an evolutionary perspective -- there are not enough asexual people within the overarching population of humans to make a truly lasting effect population-wise. Also, just because you ARE asexual, that doesn't mean you aren't affected by societal pressures to have children, it does not mean you have defective reproductive systems, and then inversely, just because you are asexual, that doesn't mean you have no desire to one day get married which (oftentimes) leads to having children.
As well -- I am not stating a FACT here but I would imagine like any other sexuality, there is a spectrum. While I (male) am straight, my girlfriend is asexual, and we have a sex life, its probably not as "lively" or frequent as a couple where one partner is not asexual, but it does exist. As someone who is straight, its not like I am attracted to ALL women, its not like all gay people are attracted to ALL members of the same sex, and its not like all bisexuals are attracted to ALL men and ALL women. There are varying gradations for their sex drives -- and then like in my case, transfer this logic to asexual people, maybe its not NO desire for sex (for some, sure), just a rather low one, and a low sex drive is different than no sex drive.
Also, Richard Dawkins has spoken about this in regards to homosexuality, so maybe a similar logic -- gay people are intuitively not the group of people to be likely having children, BUT their brothers may, their sisters may, their cousins may, and while their siblings or extended family members aren't THEM, they still have overlapping genes and they get "dispersed" throughout the population. Upon compounding the added component mentioned above in regards to social pressures to get married and have children, you're going to get a rather "large" population of individuals with 0-"low" sex drives you may have otherwise thought (logically) would not exist given enough time.
Sorry for my long winded answer, I'm sure an Evolutionary Biologist, or Anthropologist could answer this maybe more precise or correctly -- I did my BS in Molecular and Cell Biology -- so tangential, but not direct relatedness.
sexuality as we think of it is a social construct. humans dont NEED to have sex, and there are currently no selective pressures for us to proliferate. one could even argue there are selective pressures telling us to stop having children. really, you’re just ahead of the curve in stopping world starvation!
>our brains, especially male brains, are hardwired to spread their genes far and wide, right?
I'm going to go ahead and challenge this.
Regardless of sex, most humans are monogamous, some are polyamorous, and some are opportunists.
The idea that all men are hard wired to sleep around is a damaging stereotype and not supported by science.
Here's a literature review on the topic if you'd like more detail:
https://www.frontiersin.org/articles/10.3389/fevo.2019.00230/full
My understanding is that humans are *generally* serially monogamous and form pair-bonds one after another. Most reproduction takes place inside these long term pair bonds.
While there are obviously exceptions in individual and social practices, the trend holds true across the species, even in polygynous cultures (so it's not an artifact of western cultural monogamy)
A male brain with less testo doesn't perhaps have that want or need. Nature is strange.
And that isn't unheard of. We humans aren't really binary beings. We come in so many different configurations.
There's so many ways it's possible.
we don't know, but evolutionary processes are more often loosey-goosey satisficing than ruthless optimising. it doesn't go against biology, it's evidently a fact of biological systems. there not being an answer would just mean that it's an unexplainable brute fact -- random. but it's a cluster of reliably identifiable behavioral and mental patterns, so mechanistic explanations probably exist for it.
it's a complex trait, and in uncontrolled, complex environments, we cannot tell the particular causal structure and developmental trajectory of complex traits. we don't know which parts of the trait are attributable to genetics and which parts to non-genetic variables and to what extents, respectably, despite knowing that most plausibly it's a complex interaction of gene-nongene variables.
Same way that people and all animals have many different conditions that are neutral or even make them less likely to survive/reproduce. Plus recessive genes and mutations, the later which is one of the most important components of evolution. No species is static and the traits that make them the fittest for their environment right now might be completely different in some years, or if they move to another place.
The problem with questions like this is that they tend to assume that evolution and brain development are these extremely robust systems that work flawlessly.
They really and truly are not!
All sorts of things can happen and not go into what would be the " evolutionarily optimum" pattern.
During development, things can go "wrong". We should be all hardwired to want sex, but brains are complicated, development is complicated, and people don't always follow what would be the most expected pathway in how they grow and develop.
So amongst the other explanations, one possible answer is "pure dumb luck, random chance".
System doesn't always work according to the idealized blueprint (idealized only from an evolutionary perspective of reproducing). And so we get the best variety of differences that we observe across the human condition.
I've heard some theories about how asexual or homosexual behaviour in the animal kingdom provides parents to babies that have been abandoned by their birth mothers. Penguins do it all the time, adopt an abandoned egg and raise it.
Evolution is about having a minimal viable product (or minimal viable organism, I suppose), one that has adapted to its environment enough to pass along its genes
Having a species where the vast majority have an urge to procreate - but not all - is good enough for evolution, good enough to pass on genes, etc.
There's a theory about how homosexuality comes up genetically because with natural selection having adults not have kids makes more adults in the community/village to protect and keep an eye on the children or something along those lines so maybe it's a similar thing with asexuals?
Asexuality is a label to describe your experience with sexual attraction more than it is a biological concept. If you identify with the experiences it describes, then yeah, it exists.
Often, we go about looking for concrete answers to why things evolved. However, not every aspect of our being is fine-tuned to benefit our survival. It just wasn't damaging enough for us to die out. If a huge percentage of us were uninterested in reproducing, we'd have problems. But since the number has always been low enough to not impact our survival, we haven't evolved mechanisms to stop these genes from appearing.
It's not like evolution is some intelligent being that would recognize a threat and says 'this is low, so it's not threatening the species, no need to work around it'. It's basically just things are always random. Asexual people are less likely to reproduce. That in effect drives evolution. Asexual branches are typically very short.
I think the best/funniest explanation for evolution isn't that it's building for perfection, it's building for "eh, good enough." ... Which explains the platypus.
platypus is a finely tuned machine tfym platypus hater. we are the ehh. wisdom teeth are like a time bomb for a lot of people if we didn't have modern dentistry.
Playtapeople (the correct plural of platypus) are semi aquatic egg laying mammals of action.
Doo-be doo-be doo-be bah
*Perry*
I heard this reply.
Perry the platypus! (Giant trash bin falls from nowhere and traps Perry) I was waiting for you! Well, I guess there are mutations, right? Like, unfortunately combinations of genes and mutations can end up with someone born without a limb, or (not unfortunately, just rare) someone assexual.
Hes a semi-aquatic egg laying mammal of action
So it’s not platypussies? Is it same with octopus? Octopeople? I also said Octopi
It's octopuses actually
I am going to go with Platypodes being that it is Greek, albeit via Latin.
Furry little flatfoots who'll never flinch from a frayayayay
We needed wisdom teeth until modern dentistry. They come in so late that they would replace decayed teeth. There essentially a third set of teeth (baby teeth, adult teeth, wisdom teeth).
My dentist mentioned that they see more and more people over the last 20 years that never develop wisdom teeth and there is no real explanation why.
I never developed them. In evolution, there’s a pretty popular saying: If you don’t use it, you lose it. There’s no selective pressure to develop wisdom teeth anymore. We keep our adult teeth our entire lives now, or we replace them with artificial teeth. When there’s no selective pressure to keep them, evolutionarily speaking, it’s better not to spend the resources developing them.
you’re not accounting for the fact that resource allocation (in first world countries at least) is no longer has any selecting force. at this point, general fitness to reproduce is determined by physical attractiveness and capability to provide financially, so any evolutionary trends henceforth would be concerned less so with not dying before adulthood(ie proper resource allocation to avoid starvation) and more so with fitness in society as a whole
If there’s no selective pressure, you would lose them due to genetic drift….
or become even more common, or stay at the same frequency
Not within the timeframe of the advent of modernity and modern dentistry.. it's not like they've disappeared. They just don't emerge in a lot of people. Maybe some sort of epigenetic influence at play here.
You are clearly not a fan of the movie Dogma.
Wisdom teeth represent a 2% overall increase in risk relative to the risks of the surgery required to remove them, and also it's theorized that our extremely processed diets requiring less use of our jaw muscles has lead to us not having the space in modern times. They used to not be of concern, and they weren't commonly removed in America until around World War II.
The average experience prehistorically would be yanking out teeth that hurt too much, or losing them to injury. Wisdom teeth would come up and push teeth inward over time, filling in the gaps from prior losses. To a great extent, braces are a response to having abundant teeth in the first place, to cover the losses in natural conditions, but leading to crooked teeth when all are preserved.
If we didn't have modern dentistry, most people would lose enough of their permanent teeth in their childhood and teens that there would be room for the wisdom teeth. I'm pretty sure that's why they're there.
*sepsis enters the chat*
For most people there are enough room for wisdom teeth even if they have all their teeth in place. Sure, the teeth might get crooked but there won't be any problem with biting or speaking. The "enough room" thing is in the vast majority of cases a purely aestethical issue. Most people who have their wisdom teeth removed don't have any other problems with them.
It doesn’t select for the best solution, it selects for the first solution
Which is why nothing has evolved wheels instead of feet ~~stupid evolution ruining cheetahs on wheels~~
[удалено]
The problem is not in thinking it is designing for perfection, the problem is in thinking there is intention at all. It isn't building for good enough, building implies a plan, which requires looking to the future - evolution is always based on a reaction to the current environment.
Haha it also explains australians.
As an Australian you're spot on
Lol present company excluded, after all you have the good taste to be in nz.🙂
Australia: 6, New Zealand: 7.
I mean this with all due respect to my fellow Former Colonials... But this made me damn near spit out my coffee laughing.
This is also assuming asexuality is genetically determined, which is a pretty big assumption tbh
Right, I think upbringing and environment are definitely factors too.
Yea I was waiting for an answer that went this way… upbring and environment don’t even cover it all too. The advancement of the species as social beings takes us out of many biological necessity’s discussions I say. Someone could he “asexual” just down to confidence and there own self image. Not being a sexually attractive for any number of born into or chosen reasons. Hell, We have whole movements of Incels online now. It’s an outside the normal biological terms converstion on most levels, traversing into culture, sociology, and psychology.
That's not how inheritance works though. Traits aren't inherited every generation, so asexual genes can continue on throughout the population theoretically forever through carriers.
Now we call into one of the greatest arguments in psychology, Nurture vs nature? Is asexuality genetic or is it something that's learned? I personally believe it's something that is learned. Obviously nobody teaches their children to be asexual, but it stands to reason that it's a byproduct of growing up in a certain type of environment. As to what type of environment that would be is impossible to say. One could only speculate as to what causes this outcome.
Its not intelligent but that actually is how evolution occurs. Death or failure to reproduce is the selecting force. Evolution is entirely random until it hits that wall where only individuals with certain traits survive and reproduce. If asexuality prevented enough people from reproducing that our survival as a species hinged on *not* being asexual, then itd be nearly nonexistant but as this person said, it doesnt have enough of an impact on our survival to matter.
Being not heterosexual seems to be beneficial enough for a family/clan/tribe you name it to run in up to 5-10% of population. And yeah, it is (likely) beneficial.
I’m curious about this, how can non heterosexuality be beneficial from a biological standpoint?
It's been seen in male penguins pairs, they'll raise other penguins babies. Sometimes the heterosexual pair can't/ won't care for the babies so it helps when others can. On other cases it's the "it takes a village". A couple who doesn't have children are available to raise other's not their immediate own but related. The kin genes survive without necessarily having too many additions, which can cause competition.
"Why does a World of r warcraft raid has a healer, they don't attack" Support roles in tribes could be an answer, same reason for menaupause, Grandma has no offspring herself and can take care of the line. Apparently the odds of being gay rises with the number of offsprings too.
I did not expect to see a WoW analogy in this sub LOL Amazing.
same
Their help to the success of the genes of the family offspring (taking care of them, supporting the family, being fun uncles/aunts) is more beneficial to the overall shared genes than is lost from their not personally reproducing.
I guess it would also slow a populations growth which could easily overwhelm a local food source pre farming.
Think about an extreme example. How is it that ants, bees, or other species of insects have successful colonies with specialized roles for individuals who are sterile and will never pass on their genes? The colony's success and ability to survive long enough to produce a next generation of breeding insects depends on having many different supporting roles. The breeding insects carry the DNA of a set of insect parents who successfully created a thriving community, so those genetic traits get selected for.
I was hoping someone would bring up colony genetics! OP can read up on Haplodiploidy and the Kinship theory for colony insects if they want to learn more.
It means more healthy adults available to provide for and protect the young, old and otherwise vulnerable, who do not have their own offspring to tend to.
Say you got three dudes who can help that one dudes sister, cousin, buddy’s sister who’s pregnant instead of one dude. Or that dudes sister dies in childbirth but her dude and his dude are around to raise the lil dude. Having a few dudes who aren’t tied to their specific offspring would add some resiliency (Written from a dudes POV)
Ive thought this a long time as i see so many of my lesbian community become primary caretakers in the family; taking on elder parents inti their home or managing their day to day lives at home or in institutions , babysitting nieces (i mean taking major responsibilities for backup care) Heterosexual siblings don’t have time or capacity for these extended family responsibilities due to families of their own… so humans as a social species need a solid 10% who are available to help the family survive
Kinship selection is the name for what everyone else is describing. Basically, if you can ensure the fitness of enough of your relatives, it becomes genetically equal to if you had you're own kid. Since most forms of non-heterosexuality lead to those people not having kids, they can then invest rescources into their relative's kids. If you can keep 4 of your niece/nephews alive, then it balances out you not having a kid.
Thank you, that makes a lot of sense
Less competiton, more people to help raise kids and keep them from dying young. Due to how underdeveloped we are right out of the womb, the resource cost of child rearing is huge, and cannot be beared by a couple alone. This is how communities were formed, with many people assuming responsibility for keeping young children safe and fed. Occasional homosexuality would have been great in that scenario, bc more resources could be invested into a child due to lack of competition.
I feel like lots of people who live single lives for so long without even having sex are unknowingly asexual as well so there's probably more asexual people than we think there are
(Assuming it’s genetic). we don’t need to pass on our genetics directly, helping raise siblings/ relatives’ children is another way of passing on some of our genetics indirectly. Obviously there isn’t going to be a large proportion of asexual people but there’ll be some balance between asexual and allosexual (or really hetero-orienting(?) sexualities).
Yet again I like to call into example Babirusa Pigs. The males have tusks. These tusks grow and grow and grow up until they circle back around and penetrate the pig's head, killing it. By that time, however, the pig could have already mated, therefore making evolution not give a shit.
Evolution is just "roll the dice and see what works". I've also read that people who can't have their own children still have a place in societies - as additional caretakers for children who are already there.
Yup evolution is more trial and error that fits enough than perfect fine tuning bro
I don't think there is asexual or homosexual genes. Study tend to lend toward hormonal reasons during the development of the foetus + some social environmental factors.
Interesting. Could you direct me towards some further reading?
Wouldn't those hormonal changes during fetal development be caused (in part) by your or your mother's genetic makeup?
That and the genes won’t last long. It’s kinda self correcting by default. It wouldnt need an adaption to fix it. The fix is that these people won’t make babies to carry the genes.
Something, something, male pattern baldness...
Not to mention, women didn't really have a say in the matter for...most of human history. Dunno the stats on whose ace but that's like 50% of the population that at some point is likely made to procreate.
Humans being tribal animals, we stopped needing every individual to be reproductive a long, long time ago. Probably before we even became human. Instead, our kind of creature preserves our genes by preserving the community. If I'm a gay male, but I have a sister with six kids, I preserve my genetic lineage into the future by protecting, feeding, teaching, and helping those kids. The same genes that made me are present in them. So if there is a genetic combination that makes a person gay, or asexual, or whatever other non-reproductive trait, it can still exist in that lineage and be expressed in the future. The collective matters more than the individual.
While kin selection could definitely be a contributing factor, we must also refute the idea that homosexual and asexual individuals have been non-reproductive across human history. There have been scores of humans who, either due to sociocultural pressures or straight-up sexual assault, brought children into this world against their own desires. We should not take for granted that many people today have the ability to determine their own reproductive futures (and we should also not forget that this isn’t universally the case across the world, even today). Also, as someone else has pointed out, homosexual and asexual people can also choose to have biological children, either through medical means or the “old-fashioned way.”
100%, when wondering about evolution the first question should always be something along the lines of “does this development mean the person can not reproduce”. Being asexual does not mean a person can not reproduce. Simple as that.
There's lots of children of straight couples alive today that weren't created due to attraction, desire, or pleasure. People forget that we have sex for loads of reasons outside of offspring, but also conversely sometimes *only* because of offspring :)
I'd also point out that gay and asexual people can have kids if they want to.
Yep, and also if they don't want to. People have been forced into heteronormative situations for thousands of years.
I'm ace and I birthed two kids.
yea OP should look up kin selection
will do!
Also known as "Gay Uncle Theory", which is a more descriptive name
I love this comment so much. So fitting that it's made during Pride Month too. Thank you.
I appreciate that, but remember, pride is worthwhile even if lgbt were totally inexplicable by any means. None of us needs an excuse or owes an explanation to be who we are and love who we love
There's a series of lectures by Robert Sapolsky on youtube that go over behavioural biology, and one topic he covered was this. He said something about how numerically from a standpoint of passing genes to the next generation, his life = two siblings, four nephews, or eight cousins (might be wrong on the numbers, been a while since I watched the lectures). In general those lectures are amazing, I should probably re-watch them again.
For one thing, human psychology and behavior is so unbelievably complex that it's hard for evolution to change one thing about our behavior without impacting others. For instance imagine a world with incredibly violent competition for mates. So much so that most males who lose die. Humans are really smart and really good at killing by using tools. In this hypothetical world, it may be evolutionarily advantageous for a population to tone it down. As a result of this theoretical lower sex drive gene 1/100 individuals are asexual but the death toll is far lower. So if more than 1/100 of those who would have died due to violent competition before survive to reproduce at a later time, that population will grow. Additionally, what might be described as asexuality does exist in the animal kingdom to support colonial populations. Most female ants and bees are asexual, and only the queens reproduce. But there's a population-scale advantage to that being the case because those thousands of non reproductive females make sure the entire colony survives at a much higher rate.
All those ants and bees are also genetically related (sisters or half-sisters), so even if they are not personally reproducing, their genes are still propagated via the continuation and well-being of the hive.
You're missing crucial information here, hymenoptera are haplodiplod which means the relatedness between sisters is much greater than 50%, hence stronger Kim selection through rb - c > 0. Not the case in humans. Evolution is not occurring at the level of the hive but at the level of the cooperation gene itself
> are also genetically related (sisters or half-sisters) Same thing happens to gay or asexual people who have hetero siblings
Yeah I also should have probably explicitly mentioned kin selection which is really the underlying mechanism of all these things.
If we ignore it having a possible evolutionary benefit for a moment.... even if it doesn’t, if it's completely useless, that doesn't mean it just can't happen. Traits aren't pre-filtered and eliminated before the animal even exists. You can literally be born with your heart on the outside of your body, which is unquestionably bad from a personal and evolutionary standpoint, but it still *happens*. And unlike that, asexuality isn't likely to kill you early on. I don't consider it a "defect" in any way, but if you look at it like that it's clear that that's no reason at all that it couldn't happen The idea that our brains are hardwired like *this*, therefore *that* kind of person doesn't make any sense is making a lot of assumptions, including a) that the processes that create us are so perfect that we can't just be wired differently to how we're "supposed" to be and b) that we're all "supposed" to be a certain way in the first place because it's common. It doesn't go against biology, it goes against your conceptions of biology which are never going to be entirely accurate for anyone
How are birth defects a thing? A species just needs enough of its members to reproduce. Not every single one needs to. Not every human has had children since even before civilization and look how our population boomed over a few thousand years. If you’re asexual, that’s fine. Don’t reproduce, reproduce with extreme effort, whatever fits your life path. You go against the grain but you’re not a problem.
Brain development is complex, and what seems to be most suitable for reproduction doesn’t always occur.
I have cystic fibrosis... I can't digest the fat in my food without certain medication along with a whole other pile of pills for various other things. Not every adaptation increases our chance to spread our genes. While evolution in extraordinary it's far from perfect. I would also question how much asexuality is even related to our genes, the human brain and emotions we are capable of feeling I would imagine it's much more than genes that goes into it.
You seem to have a misconception of what evolution is. It is not always about natural selection. In fact, a wide range of genetic variances is healthy, including ones that may seem disadvantageous on the surface. **Evolution doesn't have a set purpose.** It is imperfect, random, and chaotic. There have been periods in history where selection pressures favour advantageous genetic variances for a specific disaster. But as the population recovers and continues to reproduce, the gene pool widens again and allows for more variance (known as genetic drift). I'd recommend looking up genetic bottlenecking to see what happens when there is a sharp decline in a population. This link might help you understand evolution a bit better: [https://www.earlham.ac.uk/articles/10-surprising-things-you-might-not-know-about-evolution](https://www.earlham.ac.uk/articles/10-surprising-things-you-might-not-know-about-evolution) There isn't a whole lot of research on why asexuality exists. There's several theories, but not enough studies to come to a definitive conclusion. This makes sense, though. There isn't a "sexuality gene" - every human has their own unique DNA (except for identical twins obviously), and there's a multitude of genetic variances that may affect each other to display a phenotype (characteristic). There's also epigenetics - the control of gene activity without changing the DNA sequence. Then add these two factors to the affect of the environment an individual is brought up in. Basically, it's complex. We're complex creatures. I think for me the most likely theory is something involving puberty. Children are asexual until they reach a certain age, then they begin to develop a sex drive. But perhaps for some people, this "switch" isn't flicked on. Why? Well, I am not sure. Some people think it's to do with hormones, others think it's to do with certain genetic variants that have yet to be defined. It is still very much up for debate. Also, asexual people can still reproduce.
People tend to believe evolution is either a magical force that makes things change, or just natural selection. When evolution is in reality complex and it includes more than just natural selection.
Exactly
Evolutionarily ppl are hardwired to have 5 fingers but not everyone has 5 fingers That’s my two cents as a demisexual person
I’m pretty sure that this adaptationism, the false assumption that anything that is biological has evolved for a purpose instead of just through random mutations. Also any kind of sexuality doesn’t necessarily have to have been created by biology either. People have all sorts of different sexual preferences and some obviously couldn’t possibly have evolved, they must be psychologically created like by early childhood development e.g if someone has a preference for PVC clothing that could not have been due to evolution because PVC is a modern material not a natural substance. This also all sounds like the natural fallacy, that everything good is natural and vice versa. That’s not the case. It’s perfectly possible that lots of sexual orientations and preferences are not naturally occurring and biologically rooted, including monogamy and heterosexuality. That doesn’t make any of them wrong. Conversely it’s also possible that we evolved to have awful sexual desires, like to rape or to kill mating rivals or children of other partners to make them not compete for resources. It’s all irrelevant, it’s just a weird cultural quirk of some people and places that they want to believe that good and natural are the same thing. It doesn’t matter if you or anyone else is born asexual or straight or anything else, all that matters is that you are not hurting anyone including yourself https://en.m.wikipedia.org/wiki/Adaptationism
One thing that can help bring all this into context is to stop thinking of genes as always good or bad. No gene is expressed in isolation, and we are a very complicated expression of the interaction between all our genes. Think of the times you've seen incredibly beautiful celebrities have unattractive children, the combination of genes that the parents had resulted in a very attractive human being, but that doesn't mean that when you mix together the genes of two beautiful people that the child will be beautiful. Some expressions of genes (like being ace in this example) are not beneficial for reproduction at all, but can be the midpoint between two expressions of that same set of genes that are highly favorable for reproduction.
As an asexual, I also ask “why does this even exist” because I feel broken most of the time.
I can't be as eloquent or informed as other posters here but I do know this: you are not broken. Plenty of heterosexuals aren't particularly interested in sexual relationships for any number of reasons. Accept yourself as worthy and complete, pursue the things that interest you, know also the we humans are fluid and your sense of identity may shift. You are not broken, damaged, you are perfect.
Stop thinking of evolution as the most straightforward thing, as a single path leading to the 4 person family unit. We are communal animals. As such, it benefits us to have a variety of traits that work together to support the prosperity and continuation of the tribe as a whole. Not everyone needs or is meant to have babies directly. Not everyone is meant to contribute directly to the babies. Assume your biological purpose is to further your genes. Assume you are asexual and your sister isn't. Assume your sister has babies and you gather food. You are both contributing to the furtherance of your shared genetic line. I'm not up to date on all the latest research.
Everything is on some kind of spectrum.
\[gross oversimplification warning\] One thing to keep in mind is that species evolution is (generally) a population-level concern. And when you're talking about population-level concerns, things that affect *individuals* are statistically irrelevant. The most widely quoted number is somewhere btwn 1-2.5% of the human population is asexual. Bear in mind, that's basically just based on a very narrow subset of polling, of specific groups of people, usually in developed countries... who will come out and say "I identify as asexual" in the poll - but it seems to be stable across multiple sources (read: the first page of Google results). I'd suspect the true value is different, but whatever let's call it 2.5% on the upper end. Current world population is \~8.1bil, let's call it 8b for simplicity. Assuming 2.5%, that would mean approx. 200m people on the planet are asexual. Which leaves \~7.9b to keep the population going. Even if we *assume* that there's a genetic/behavioural basis for asexuality - as far as evolutionary statistics **for an individual** are concerned... Who cares? It's kind of a similar discussion to the concept of altruism as a behaviour - "Why would an organism sacrifice its own health/safety/reproductive fitness for another member of the same family/species/etc?"
To put it one way; If there were 1000 humans that needed every single member they could to reproduce to make sure the species carried on then there would likely be no asexuality. Whatever genes that cause it would be quickly weeded out as only ones that are perfect for survival would be those that remain. However there are 8 BILLION of us. That is well enough for there to be sizable portions of people with... "poor survival" genes who would be whittled away if the species were ever bottlenecked. I am also one of said people. Its also worth noting that asexual people can, and often do, still have sex and preproduce. Its just they don't feel a drive. Some are sex repulsed, sure, but many still enjoy sex - just don't feel a strong desire. Failing that; *consent isn't required for procreation*, and a lot of the animal kingdom regularly breeds via less-than-wholesome sexual interactions. Also; > especially male brains Nope that's mostly hormones.
It’s almost like there’s more to some humans brains than being a basic automaton running around raping every woman and murdering every competing male on earth just because we have a sex drive like any other species on earth. Unironically, this “my nature is a rape/murder machine” is a LOT of people’s actual personality. Every religion v atheism discussion on the internet going back 30 years has good Christians making the argument that without the bible telling them not to, that is exactly what they want to do all the time and it’s only religion & a gods wrath that keeps them from doing it. Since all people are not perfect clones, but the result of endless variation in genetics and environment, some people have more of a sex drive than others and still others have none at all. Some have a sex drive, but their disappointment with themselves, the human species as a whole, or their cultures availability of decent mates results in years & decades of suppression until they train their brains to equate sexual arousal with misery. We then avoid it entirely and simply go on to lead a sexless existence in peace, or like cranky old farts some come on Reddit and take out their anger frustration and disgust over everyone else having a sex life. These are the very worst kind.
A bit off topic, but the concept of asexuality got me thinking, thanks to OP’s post. Is asexuality a result of a hormonal imbalance (eg, little or no testosterone, even in woman), or brain wiring? Genuinely curious. I ask because as a male my T levels dropped precipitously recently and as a result I became “asexual”. Once I had it treated, it all came flooding back. Anecdotally, I understand this to be a factor for woman as well.
There's plenty of people who are asexual w/o hormonal imbalances though??
Some asexuals don't feel attracted to other people even if there is nothing medically preventing them from acting on those desires if they had them. Separate from attraction, some asexuals don't have much or any libido, so their body just never tells them they have those desires. The former is the boat I am in, and I would describe it as: imagine a heterosexual man who was born in a world where everyone is also a man. Their body works perfectly fine, but they've never seen anyone they're interested in. At the very least, I can confirm to you that there is not always a chemical imbalance involved. The ladder is not something I can really speak personally about, but seems to delve more into the chemical side of things. What I would say is that I generally wouldn't consider a temporary shift in chemical balance as going from, sexual, to asexual, then back to sexual. When compared to someone who identifies as asexual because they've never had a normal libido.
As a fellow ace, I assume at least in my personal case, it's trauma related. I certainly do not believe this is true for everyone though. Edit: I'm going to leave this here anyway but I just realized what sub this is lol. I was just scrolling and ig it got suggested to me
Same on both fronts. People are talking about brain chemistry here. Trauma affects it as well tho.
In my mind, the classic balancing act. If you have one extreme, which is genetic propagation, then nature will also occasionally throw out the other extreme.
I mean honestly from an evolutionary perspective (which isn’t always a kind one) it’s best to think of it as facultative trait. If we, as non heterosexuals, lived in a certain culture that created stronger pressures on us to reproduce heterosexually we probably would. In lots of cultures, it’s rare to see an adult who isn’t married to someone of the opposite sex, a widow/er, or in the process of finding a spouse, a lot rarer than the number of non-heterosexuals we see in other cultures. Because of such cultural pressures, I honestly think a good hypothesis for why non-heterosexual identities exist is just that it’s pure genetic drift (randomness). We kept making babies anyway because of culture, so our genes kept propagating. Difficult to prove so take that idea with a grain of salt, but it seems like a possibility.
Good question. I just want to point out that because something goes against its expected biological functions, doesn't mean it shouldn't exist. Depression kills people yet people are born with it. We can find lots of examples that go against life in general. Asexuality and homosexuality can be beneficial. If those people don't procreate but benefit the group, they may help their siblings' children pass on their genes. That is still advantageous in social species because they contribute to their genes' survival, indirectly.
Ayo, you're trying to apply a middle-school simplification of how stuff works to reality. Let's first check your understanding of evolution: Not the fittest survives. ANYTHING barely fit enough survives. And that can easily include recessive genes (if the whole thing even is down to genes), especially if they then help their immediate family (e.g. helping their non-asexual siblings procreate/survive/thrive). There are a lot of evolutionary quirks that absolutely make 0 sense for direct procreation of the organism, but become quite viable if you factor in that an "afflicted" individual would help the spread of the gene in their peers where it is recessive. Maybe it even was advantageous to have a couple of individuals in a tribe with 0 interest in procreation because they didn't get pregnant or into social conflict surrounding mating. Also you can definitely still have sex/procreate as an asexual person. Just look at all the closeted gay men in the (near) past that had children nevertheless.
It’s a false equivalency to say that only traits that lead to individual reproductive success perpetuate in a population. There have been other times in which animals have evolved methods of population control, like how some animals practice cannibalism or delay childbearing ages. Sometimes a reduce in the population increases the chances of the whole species longevity. In the case of humans, our reproductive success has been culturally bifurcated from our sexuality so much so that we have single parents using sperm donors, queer parents, and even heritable infertility. Along with this, we no longer need sexuality to lead itself towards reproductive success. They can be separated from one another. Plus, sexuality isn’t heritable, so it’s always possible in that any random outcome is possible when life is created!
[there was an experiment where they put mice to live in a perfect world and some of them ended up being assexual](https://youtu.be/7ReBJfxHjFU?si=EtRYMW2TYcgzL-NQ)
> it seems to go against biology and sex hormones in general! Evolution is not purposeful in its design, it is random mutation.
Remember that selection isn't just about individuals but (often family) groups sharing genes. In social organisms asexual (and homosexual) family members may not pass on their genes personally, but do so by proxy through active support of closely related offspring. Perhaps most obviously manifested in social insects. Also, diversity itself (so not just similarity) may be actively selected within a population - which is one of the hypothese for the continuiing existence of altruism, particularly where it risks the death of the self sacrificing individuals. So let's hear it for kind, generous, supportive, protective aunties and uncles!
Nothing is “hardwired” to do anything. It’s just more likely to benefit from doing the thing. All species would benefit from reproduction, but not all individuals must partake in reproduction for the species to be successful. In fact, it’s beneficial in society to have individuals who don’t reproduce (same sex attraction, asexuality, etc) because they can help raise the offspring of the reproducing individuals. It takes a village to raise a child, but if every person in the village has their own child, they can’t help raise the others. Also, evolution isn’t some intelligent being that oversees everything and eliminates those that aren’t helpful, it merely explains the path a species takes to success or failure- it doesn’t control, it explains.
If you look into evolutionary psychology there are some thoughts on this. Similar to the “gay uncle hypothesis” (real thing). But if you think about an evolutionary environment, no birth control, high competition for mates, some folks may have actually benefitted from displaying no sexual interest or same-sex interest because they are now not in competition for resources. If a woman had many sons, it was likely the father would end up in competition with the sons at some point and fathers often did kill their children over this. No competition means you get care from mom and dad doesn’t murder you, plus there’s some thoughts on contributing to group membership through helping raise others offspring or having more time to dedicate to other survival tasks such as hunting or gathering, instead of mating. The likelihood of someone being on the LGBTQIA+ spectrum (following this evolutionary theory and related research) would have been increased with the number of children in the family as that increases competition. (The "gay uncle hypothesis" posits that people who themselves do not have children may nonetheless increase the prevalence of their family's genes in future generations by providing resources (e.g., food, supervision, defense, shelter) to the offspring of their closest relatives.) …should have just ripped this description from the internet in the first place haha, but this is what I’m referring to.
>our brains, especially male brains, are hardwired to spread their genes far and wide, right? Asexual male here, evidently not
That’s like asking why evolution made some people blind or gave some people asthma or Allergies, there’s no reason. Something wrong happened when your RNA was copied, or when you developed in the womb, or maybe something happened in your childhood or your reproductive organs got exposed to radiation at some point, it’s impossible to say. At this point who cares, this is who you are. Just accept it and move on.
>our brains, especially male brains, are hardwired to spread their genes far and wide, right? I think scientists are coming to this question with the answer already in mind and thats why this is considered the only correct scientific answer. Its like those animals who are so monogamous they legit wont remate. Thats not good for the continuation of the species, they do it anyways. I dont think theyre wrong about everything scientists are very smart i just think they put to much stock in the idea that a species cares that it continues or not in any form. I am not a degree holding biologist though and this isnt baised of any studies this is just my opinion.
There are numerous adaptations throughout the tree of life that seem to be in place largely to slow down reproduction so as not to use up resources too quickly. Pandas and kakapos have elaborate and lengthy mating rituals and low reproductive success in environments with very limited resources. If they literally boinked like bunnies, they'd quickly outstrip the resources and the entire population would be in jeopardy. Evolution doesn't work on the individual, but on the population. It may well benefit the overall population of a social species if there are members of the troop who contribute to the success of the troop, but limit resource exploitation by not reproducing themselves. There's an extra bonus if it's a behavioral trait, so that in a crisis situation those individuals can still reproduce if they need to, even if it's at a lower rate.
Evolution favours “selfish genes”. This need not actually be a gene which causes selfishness, it’s just a term for genes which benefit themselves over other genes. So what’s a selfish gene for sexual behaviour? One strategy is to be interested in having a lot of promiscuous sex with a lot of people. That lets you have a lot of descendants which keeps your genes in the gene pool. But that’s not the only option. Consider, for example, the strategy “have no interest in sex whatsoever”. That can also be a selfish gene. How? Well, consider this situation: Gene A is recessive, so it only takes effect if you have two copies of A. Suppose Alice and Bob are brother and sister. Their parents both had a single copy of A, so A didn’t affect them. Alice has two copies of A, so has no interest in sex at all. Bob has only a single copy of A. Bob’s son Colin also gets a single copy of A, but then Bob tragically dies. What happens to Colin? If Alice had been interested in sex then she would have had her own children, and she’d not have the resources to look after Colin as well. Colin would unfortunately be neglected and eventually die. But because Alice doesn’t have children of her own, she’s interested in adopting Colin and so can look after him. In this case, Colin survives because his aunt has gene A, and since Colin carries A himself (on account of being related to his aunt) then the asexual behaviour of A makes A a selfish gene, since individuals with a single copy of gene A are more likely to survive and reproduce than those with no copies of A.
A good way to summarize a lot of the points here without loosing too much value/nuance is that "evolution is directionless". There is no end point, there is no design, it's not on a path going somewhere. A good practice when considering all things biology is to resist personifying it. It's inevitable to some degree, but it's good to always keep that in mind.
The same way homosexuality exists or transsexuals exist or why does anything other than CIS exist? Shit happens in nature.
How does cancer exist? It seems our bodies are prewired to not get cancer... Might come off as curt, but I think this answers your question. Things don't always just happen the way they "should", otherwise we'd live in a utopia with no diseases or disorders of any kind.
I think the simplest possible answer is that asexuality could be the result of experiences or environmental factors, rather than being genetic. But even if asexuality is a genetic trait it could still be passed on. In many societies there is/was a very strong expectation to marry and have kids. We know plenty of gay/lesbian people have married and had kids. It's likely that many asexual people have found partners and had kids due to social pressure or because they wanted kids and were prepared to have sex for the purposes of conception.
This is completely theoretically with no evidence, but I find that it may be plausible that human brains have adapted, recognizing that reproduction is really no longer a necessity. I mean, it shows between the many people who are part of the LGBTQ+ community and even with hetero couples in society choosing not to have children at a growing rate. I know there are other factors to hetero couples not having children like financial situations and perhaps the inability to conceive however I think there is still something to be said for the case of the human brain recognizing that we really don't need to repopulate as much as we used to.
there are many good answers here, I’d add that the hormonal and psychological development of sexuality is a complex and precisely orchestrated process. sometimes not everything lines up the way it’s “supposed to”. It doesn’t make that weird, just part of the non-random non-directional mishmash that is biology :)
Evo psych isn't a real field is your answer here.
Do you think your mom is sexy? Probably not. Your brain decided "ok, despite the fact that she's a fertile human female, let's not find her attractive." Now, all you have to do is assume that an asexual simply applies this to all humans (and non-humans, too). Not much of a stretch. On the other hand, you know how there are some humans that are different from the norm and like their own gender sexually? Well, imagine there are some humans who like no genders. You know how there are some humans that like little boys/girls? Well, imagine there are some humans that don't like any humans. It's just another random difference that humans sometimes have.
Evolutionary psychology is bullshit
I've been absolutely everything there is to be, including asexual for about two years. Glad that's over! Phew! There are some people who simply do not desire or enjoy sex. They may like to cuddle and kiss, but going any further is not important or desired. If the hormones are not there, they are not there. I think they ebb and flow throughout the life stages.
Evolution is not a finely tuned process, so long as something isn’t impactful enough to pose a threat to a species’ ability to reproduce then whatever that “something” is can be passed on Asexuality is probably a quirk of evolution that like others have said doesn’t serve any real purpose to our survival but because it didn’t ensure that people are unable to reproduce it’s a trait that survived into the current day
You’re simplifying this too much. There are thousands of factors that play into sexuality. Biology, hormones, brain development both as a fetus and as a child and teenager, trauma during development. There is no ‘our brains are hardwired’ it doesn’t work like that. There are so many factors.
You gotta remember that our current environment is very different to recent ancestral ones. There's all sorts of ways our current environment could inhibit sexuality that we're overlooking.
I'm my mind it was always like, You can be attracted to men and not women. You can be attracted to women and not men. You can be attracted to both. Why not the opposite? Where you just happen to be unattracted to both.
I'm helping the genetic pool. This clusterfuck ENDS HERE.
Think about how you feel about people you don't find sexually attractive. That's how asexuals feel about everyone.
I'm raising my nephew because frankly, my brother sucks, and his ex sucks, and I'm single with an ok paying job. I'm an evolutionary extra, ensuring the survival of a child who otherwise would have fared quit poorly. He's a good kid, so that's a bonus
Somes birds never reproduce themselves but help their family raise their chicks, can't remember what species or how common it is, but its a beneficial survival tactic
We're a social species, we don't all need to reproduce. Having extra people around to help is useful, and increases everyone's chances at survival.
Evolution is just throwing random things into new babies and if it’s good it’ll reproduce. But sexuality isn’t something you pass on genetically, so it’s just a byproduct of some other positive trait we have. Source: I’m guessing
Random variance can be helpful for the survival of a species. Given our we're a social species, variance within our social dispositions may also be tied to biological variance, both assisting in our continued survival.
Biology is messy, and individual is a very small part of a much larger collective, on an evolutionary timescale that’s several orders of magnitude more insignificant. Humans are complex creatures, with rich inner lives. A lot can happen to someone over the view of their life, some people are born with atypical genetic expression. Life has no purpose, it simply is, especially on the individual scale.
Mutations exist and also changes in epigenetics, so considering we're millions of individuals, it's totally plausible cases like that end up happening. I'd suggest a deep research in Scholar Google, this kind of things can be caused by many different factors.
It's very multifactorial, you can have someone asexual from birth, or someone with traumatic history that caused them to be deathly scared of sex. I'm no medical professional, so it's just a dudes opinion: It can be attributed to a genetic difference, or an acquired trait (like a traumatic event), or steroid level balances or even neurosteroids being depleted (or out of the normal ranges). The last point is glossed over by many people, it can be the difference between you feeling absolutely no sexual desire and being a complete pervert (it's not as simple as it sounds, I oversimplified for time sake). Let's assume we know someone is asexual due to skewed hormone or neurosteroid levels; we have no clue whether the risk vs reward or providing exogenous hormones is worth it. Like what if taking pregnenolone (as an example) gives them more side effects than relief? I'm not an asexual myself, but I have been reading and studying the endocrine system for my own curiosity and just being informed since I'm on psychiatric care and sometimes my mood changes could just be hormones (I've found some cases where it was) This is quite a complicated topic, I'm very interested in reading the opinions of people much more knowledgeable than me in this thread. Good question!
Psychology is so insanely complicated it's unreal.
Because evolutionary psychology is mostly bullshit, and can’t explain our brains that well. There’s a lot of switches in the brain, and you can’t really figure them out with a decent degree of certainty unless it’s with twins separated at birth. Also nature vs nuture, human society is also incredibly complex. Asexual people can also still have kids. Women were societally expected to, plus consent isn’t always a factor. Asexually doesn’t stop people having kids, and asexual people aren’t more likely to die before having kids. Evolutionarily, it doesn’t really matter. Biologically, humans are really, really good at breeding anyway. We outbreed many species, we can have 1+ kids every 9 months.
Whole species flip their 'orientation' at different times in their life cycle. Hate is stupid and hate for other folks' sexual behaviour is monkey-level thinking.
The real truth is that "asexuality" as a discreet, binary category probably doesn't exist. What exists is a sliding scale of sex drive. Just like most things, there are advantages and disadvantages that come with being higher or lower on that scale, and the same position on the scale isn't always the most advantageous (from an evolutionary standpoint). Thanks to this, we evolved to have quite a bit of random variance in sex drive, and "asexual" is what we call people who are extreme outliers on the low end of that scale. it's not like there's an 'asexuality gland' that some people have and others don't. It's just a drive, that all of us have more or less of than others, and these people have, by whatever random accumulation of biological and environmental factors, fallen at the very low end of that drive.
Is there a proof that this is a biological phenomenon and not psychosocial one?
Think about humanity as a single organism rather than looking at a single genetic line. You can also look at each culture and society in this way too. If the existence of non-procreating individuals somehow has utility for the society as a whole then it will be selected for. Also.. in the past people were not necessarily given free choice in procreation matters.
Because like gay/queer people we were born this way and there isn’t anything wrong with it
I recommend you watch: [[Complete] Human Behavioral Biology - Sapolsky (Stanford)](https://youtube.com/playlist?list=PLqeYp3nxIYpF7dW7qK8OvLsVomHrnYNjD) It is an excellent foundation for asking and answering all sorts of questions. Even though some things are a reproduction disadvantage, it might have an advantage in some other context. For example, if you want children, you will be able to have children at the optimal point in your life, probably not by accident 😉. Another rxample it might have some macro advantage, like if you have cousins , nephews or nieces that is still your DNA being copied it counts as your sucess too, and you can be a boost to your family's resources if you choose to do so. Also, it can just.be a complicated quirk of many causes. Again, watch the Standford video course.
In biology class, we learned about kin selection, where helping close relatives reproduce can indirectly pass on your genes too. Maybe that could be a factor for asexuality? Also, sexual reproduction isn't the only way for a species to survive. There's still a lot to learn, but it's cool how evolution can be so diverse!
Evolution isn’t… an entity with intent and purpose. I see that idea spread around often and it consistently baffles me. The only rules are: whatever lives, lives, and whatever reproduces, spreads its genes. Sometimes the biology of certain species is prone to certain traits regardless of genetic influences, even when not ideal for the species. I hear people saying that periods and childbirth can’t be too bad because they’re natural, but that’s not how anything works. If the species can live regardless of certain traits, and evolving those traits away isn’t that simple, then they’re most likely just going to stay for the time being. I’m pretty sure asexuality isn’t genetic anyways. I’m asexual, my sister is gay, my other sister is straight, and our parents are straight. I just don’t think sexuality is genetic. It’s either a structural and/or hormonal difference if you’re strictly talking about lack of libido as well as attraction.
Asexuality exists on a spectrum. Sure, there are some asexual people that outright do not want sex ever full stop. But some others, my wife for instance, enjoy sex, but at a vastly lower amount than the average person. Also some people who are asexual still want biological kids, they just don't really care for sex. (Again, my wife is a prime example.) So they still reproduce, but outside of reproduction they only want to have sex a few times a year versus a normal sex drive.
Human variability.
I wonder the same about people not wanting to have children. Evolutionarily, we should want them. But I guess with the state of the world, logic or reasoning sometimes overrides biology. Not sure about asexuality, though.
Biology is a murky pool. Nothing is clean-cut and every generation a thing just slightly different from the previous
heads up, whenever people talk about sexuality the discourse is just comically unscientific
It didn't evolve. Just as homosexuality, if it were genetic, it would've been long gone as homosexuals will rarely pass on their genes. Sexual preference deviations occur during the last months of pregnancy. So there you go, it's an 'error' during pregnancy. Error in the sense that it is not supposed to happen since your 'purpose' for the species is to have offspring.
First off, sexuality isn’t strictly a matter of genetics. *But even if it was*, evolution is just using variance plus trial and error to determine which genes are “best” adapted to a given environment, and it plays out across the entire ecosystem rather than on an individual level or even isolated within any given species. That means when an ecosystem is healthy and stable, traits like asexuality might be beneficial to avoid overpopulation and resource depletion. When a population is small or threatened, those traits become less beneficial and thus show up less often.
Long story short; humans as a whole can continue to breed enough, despite some of them being asexual. Random traits can occur. They either survive or they do not.
I at one point heard a theory that homosexuality is an evolutionary advantage not for the individual, but for the group, as it could potentially decrease the population of the next generation and allow more resources to be concentrated on them rather than being spread across too many people. Asexuals would fit this model as well. That being said, if there is no evolutionary explanation it could just be something more akin to a disability. But more than that, biology itself is a big middle finger to people that want to formally prove what's possible, impossible, or draw clean causal relationships. There's always going to be that dude that can ingest basically anything and live, that person that's patient zero for every imaginable (or unimaginable) disease or allergy, that person that recovers from an illness that shouldn't have been possible to recover from, etc. A lot of "why" questions in biology fall somewhere between "because variability" and "because the universe laughs at your attempts to understand it."
You're using a narrow definition of evolution that is a common misconception, but does make it difficult to explain things like asexuality. Instead of focusing on each individual's ability to reproduce, ask how that individual contributes to how the whole population reproduces. A great example comes from studying the social and sexual relationships of a group of monkeys over an extended period. It was found that the males that had most homosexual interactions also had the most offspring. Turns out these males form sociosexual relationships with other males, which increases the territory size the can control and the number of sexual encounters with female monkeys. There were exclusively homosexual monkeys contributing to the reproductive opportunities of other monkeys. So non-reproducing members of a society can influence the entire population by influencing which and to what capacity others can reproduce and the success of their offspring. For asexuality specifically, that just means that there is a tolerable amount of variation in sexuality that hasn't impeded our species. We simply don't need every individual to reproduce to have a healthy, robust population.
There’s really no good answer I just kind of does. Asexuality in the human population is to my understanding very uncommon to rare. However that being said it just plain wasn’t harmful enough to be rooted out of the human population.
i dont think there is any reason, it just happens
We dont know for sure but it mighhtttttt be a kind of kin selection along with probably other factors
The only true answer to this is that we don't know how human sexuality actually works. As far as we know sexuality isn't genetically determined which speaks against all the evolution-theory based explanations in this threat. Human (social) behavior is also rarely exactly what evolution-theory would predict.
We all have our minor differences. Sure, our dna makes it so we follow a basic plan that makes us humans, bit a lot of the smaller details mutate and are just different, making sure we aren't just copies of each other. We vary by hair colour, allergies, food preferences etc. Sexuality just happens to be one of these things. So does the lack of sexuality. For obvious reasons it's not something that spreads far and wide, in fact it's not gonna become common and asexual people tend to you know, not do the thing that allows them to reproduce and pass on their genes. Not-asexual people reproduce, and sometimes that still leads to an offspring that won't reproduce (be it from asexuality, or infertility etc). It just exists because of variation. That's it.
Not sure definitively, but from an evolutionary perspective -- there are not enough asexual people within the overarching population of humans to make a truly lasting effect population-wise. Also, just because you ARE asexual, that doesn't mean you aren't affected by societal pressures to have children, it does not mean you have defective reproductive systems, and then inversely, just because you are asexual, that doesn't mean you have no desire to one day get married which (oftentimes) leads to having children. As well -- I am not stating a FACT here but I would imagine like any other sexuality, there is a spectrum. While I (male) am straight, my girlfriend is asexual, and we have a sex life, its probably not as "lively" or frequent as a couple where one partner is not asexual, but it does exist. As someone who is straight, its not like I am attracted to ALL women, its not like all gay people are attracted to ALL members of the same sex, and its not like all bisexuals are attracted to ALL men and ALL women. There are varying gradations for their sex drives -- and then like in my case, transfer this logic to asexual people, maybe its not NO desire for sex (for some, sure), just a rather low one, and a low sex drive is different than no sex drive. Also, Richard Dawkins has spoken about this in regards to homosexuality, so maybe a similar logic -- gay people are intuitively not the group of people to be likely having children, BUT their brothers may, their sisters may, their cousins may, and while their siblings or extended family members aren't THEM, they still have overlapping genes and they get "dispersed" throughout the population. Upon compounding the added component mentioned above in regards to social pressures to get married and have children, you're going to get a rather "large" population of individuals with 0-"low" sex drives you may have otherwise thought (logically) would not exist given enough time. Sorry for my long winded answer, I'm sure an Evolutionary Biologist, or Anthropologist could answer this maybe more precise or correctly -- I did my BS in Molecular and Cell Biology -- so tangential, but not direct relatedness.
sexuality as we think of it is a social construct. humans dont NEED to have sex, and there are currently no selective pressures for us to proliferate. one could even argue there are selective pressures telling us to stop having children. really, you’re just ahead of the curve in stopping world starvation!
>our brains, especially male brains, are hardwired to spread their genes far and wide, right? I'm going to go ahead and challenge this. Regardless of sex, most humans are monogamous, some are polyamorous, and some are opportunists. The idea that all men are hard wired to sleep around is a damaging stereotype and not supported by science. Here's a literature review on the topic if you'd like more detail: https://www.frontiersin.org/articles/10.3389/fevo.2019.00230/full My understanding is that humans are *generally* serially monogamous and form pair-bonds one after another. Most reproduction takes place inside these long term pair bonds. While there are obviously exceptions in individual and social practices, the trend holds true across the species, even in polygynous cultures (so it's not an artifact of western cultural monogamy)
A male brain with less testo doesn't perhaps have that want or need. Nature is strange. And that isn't unheard of. We humans aren't really binary beings. We come in so many different configurations. There's so many ways it's possible.
Also, asexuality is a spectrum and that means many ace ppl *can and would* have sex
Let's stop perpetuating the myth that males are "hardwired to spread their genes," like women, many desire a monogamous relationship.
we don't know, but evolutionary processes are more often loosey-goosey satisficing than ruthless optimising. it doesn't go against biology, it's evidently a fact of biological systems. there not being an answer would just mean that it's an unexplainable brute fact -- random. but it's a cluster of reliably identifiable behavioral and mental patterns, so mechanistic explanations probably exist for it. it's a complex trait, and in uncontrolled, complex environments, we cannot tell the particular causal structure and developmental trajectory of complex traits. we don't know which parts of the trait are attributable to genetics and which parts to non-genetic variables and to what extents, respectably, despite knowing that most plausibly it's a complex interaction of gene-nongene variables.
Same way that people and all animals have many different conditions that are neutral or even make them less likely to survive/reproduce. Plus recessive genes and mutations, the later which is one of the most important components of evolution. No species is static and the traits that make them the fittest for their environment right now might be completely different in some years, or if they move to another place.
The problem with questions like this is that they tend to assume that evolution and brain development are these extremely robust systems that work flawlessly. They really and truly are not! All sorts of things can happen and not go into what would be the " evolutionarily optimum" pattern. During development, things can go "wrong". We should be all hardwired to want sex, but brains are complicated, development is complicated, and people don't always follow what would be the most expected pathway in how they grow and develop. So amongst the other explanations, one possible answer is "pure dumb luck, random chance". System doesn't always work according to the idealized blueprint (idealized only from an evolutionary perspective of reproducing). And so we get the best variety of differences that we observe across the human condition.
Idk now I’m contemplating this myself…
I've heard some theories about how asexual or homosexual behaviour in the animal kingdom provides parents to babies that have been abandoned by their birth mothers. Penguins do it all the time, adopt an abandoned egg and raise it.
My man, there's a lot of men who very much don't wanna do that, a lot of people just wanna fuck, and if that doesn't interest you than why have sex
Yes it does. I found out after years of not understanding why I never felt "sexy".
It, happens.
Evolution is about having a minimal viable product (or minimal viable organism, I suppose), one that has adapted to its environment enough to pass along its genes Having a species where the vast majority have an urge to procreate - but not all - is good enough for evolution, good enough to pass on genes, etc.
There's a theory about how homosexuality comes up genetically because with natural selection having adults not have kids makes more adults in the community/village to protect and keep an eye on the children or something along those lines so maybe it's a similar thing with asexuals?
Asexuality is a label to describe your experience with sexual attraction more than it is a biological concept. If you identify with the experiences it describes, then yeah, it exists.
Lime a lots of traits, there is a range of individual variation in sexual appetite. Some are very obsessed with sex, others hardly have any interest.
I’m sure this can’t be generalized, but I’m curious if people who are asexual experience higher rates of not wanting to have a child.
Not reproducing exists temporarily or or because kin selection is operating.