I really wish there was some accurate physiological test that could be used to determine if you had ADHD or not. I _strongly_ suspect I have it. As a child I could never "focus". My parents being academics from the USSR didn't "believe" in it, they just kept forcing me to sit still and study until I did.
Eventually, I got slightly better at sitting still and "focusing". I would (and still do) fidget like crazy, either pen spinning, tapping my feet, rocking back and forth while "focusing". Focusing was just me quickly switching between what I was supposed to be doing and anything else, back and forth.
The upside is now I am basically "immune" to distractions, I can always reply to slack/my girlfriend/whatsapp messages/alerts/PR feedback/emails/questions and then go back to what I was doing 5 seconds ago without any issues. I've probably switched between this comment box and coding 20 times at this point.
I tried getting an adult diagnosis in the UK to see if maybe "proper drugs" would be helpful, but was just told politely to fuck off by the GP. The reasoning was that I have a job in tech, so even if I had ADHD, it's not bad enough to warrant any treatment. Lots of coffee and listening to "hardstyle" or any music with high BPM seems to help me focus.
> I tried getting an adult diagnosis in the UK to see if maybe "proper drugs" would be helpful, but was just told politely to fuck off by the GP. The reasoning was that I have a job in tech, so even if I had ADHD, it's not bad enough to warrant any treatment. Lots of coffee and listening to "hardstyle" or any music with high BPM seems to help me focus.
If you're ever looking to chase that down again, having a successful career shouldn't preclude you from being "impaired" enough to be treated for ADHD, but you need to emphasize _how_ your life is negatively impacted to give the GP, Psychologist, or anyone else involved the justification they need to diagnose and treat you. (And if you already did this, well, maybe another doctor?)
When I was diagnosed my being relatively successful was definitely some points against, but really high level I was able to explain:
- That I had recently switched jobs, the previous behaviours _are_ impacting my work, and here's exactly how.
- Detailed some of the challenges I faced in my day-to-day life personally and how it was impacting my family.
- For questions where I am not particularly impaired, where possible I explained the coping strategies I use in order to, y'know, function, but obviously that this was still stressful and difficult for me.
The psychologist had no issue diagnosing me with ADHD and recommending my GP prescribe me medication. He was not surprised to hear that over a few decades I'd managed to develop one or two coping strategies, and the strategies I'd explained were actually consistent with an ADHD diagnosis.
I've seen a few videos of people discussing their ADHD. One thing that came across is "I can't focus" was too broad. Some of them could sit for hours on end mastering a video game. What they could not do is focus on things that were less interesting.
Mind you, these were high functioning individuals. They found ways to use their bountiful reserves of energy to earn a lot of money. Maybe there are others that can't focus on anything for a long period - I don't know.
The difference between them and myself (apart from that energy) was that I can, with a struggle, force myself to focus on most things if I'm physically comfortable. That said, doing something I don't like is struggle, and I'll procrastinate like crazy. But for them, it seemed near impossible.
They solved the problem in the same way I do for regular things I don't like doing. They incorporated it into their daily routine. Repeating a routine, even something a simple as casting a fishing line (which I guess is not that simple to do well, now I think about it), brings it's own pleasures regardless of the task. For me it takes a few weeks to add something to my routine. For them, it seemed to take months or years. The self discipline they applied to keep at it until it became a routine they enjoyed for it's own sake, was amazing.
Hey, I have had almost exactly the same experience, from the childhood experienice down to the music. For me, the functional impairment was also in things outside work, which is eventually how I got someone to refer me to a neuropsychiatrist for the full battery of tests. The treatment ended up being very helpful, but mostly for my personal life and general health.
I think this is a good example of how we mix up concepts: ADHD is just a phenotype. Then, our society classifies it as a condition because it does not go well with current circumstances. Although, both are separate things.
Is there an actual consensus on what ADHD _is_, besides a catch-all for some common concentration and hyperactivity symptoms?
People online assert a lot of things, such as "it's a dysfunction of dopamine pathways", "it's genetic", "it's a sort of autism", "it's a brain chemistry problem". But never anything that looked like a real definition backed by good science.
My own psychiatrist's diagnosis was a bunch of obvious questions that I couldn't answer honestly even if I tried. The conversation boils down to: "I have trouble concentrating and wonder if I have ADHD, I have [common symptoms backed by anecdotal evidence]. - OK, they have to affect your life severely enough to qualify. Do you think they are? - I guess, that's what I'm here to find out. - OK, let's try Ritalin." It was only helpful in that I needed to focus during a semester of studies and the stimulants did it.
It feels like I had a cough, got diagnosed with cough syndrome, and went through cough medications until they started helping the cough, and now I can describe myself as a cough syndrome sufferer. Where's the virus?
It's causes are understood to be a combination of genetic risk factors (its heritable and follows family trees), and environmental factors such as child abuse increase the odds of an ADHD diagnosis being made.
I believe it's lower than normal background levels of dopamine.
Obligatory disclaimer I am in no way a doctor or scientist. This is probably wrong. Pinches of salt all round. This is a theory I'm kicking around now and then but I don't have the knowledge to confirm/deny the hypothesis yet.
When a normal person tackles a regular task they'll get a little squirt of dopamine leading up to the task (anticipation) and then a corresponding signal when the task is done (I did the thing correctly, woohoo).[0]
When a normal person tackles a task and gets a better than expected result, they get a fresh squirt of dopamine upon completion (Oh wow, that went really well! I should consider doing this again!)
When someone with the ADHD-type brain wiring tackles a regular task they'll get the initial anticipation squirt, but upon completing the task they'll get a lesser amount (in dopamine language: that didn't go as well as I thought it would)
Compound that effect over $age years and you get someone with no real motivation to do anything, often distracted by random things that might be interesting, anxious, depression, imposter syndrome, all that good stuff - they rarely get a "I did good" signal, so nothing feels worth doing and they don't feel like they've had much success in life. Also might explain why a lot of ADHD folks have some sort of dopamine loop going on - alcohol, smoking, drugs, overeating, absolutely covering every meal in salt, etc. Something that brings up their background level of dopamine.
You do get positive effects from this - it's not all doom and gloom! - quick learners, jack of all trades, outside the box thinking, anything that might give a better dopamine response than the day to day routines
Might also explain all the "ADHD people were great as cavemen" stories that pop up now and then - nothing gives more dopamine than "holy fuck, I survived", the modern day doesn't really have many of those moments.
Feels like this would also explain why someone with ADHD can take stimulant medication and not bounce off the walls like a normal person would on the same medication - their background level of dopamine is being brought up to normal levels by the medication which in turn allows the rest of the system works as it does in normal people.
> Within the brain, dopamine functions partly as a global reward signal. An initial dopamine response to a rewarding stimulus encodes information about the salience, value, and context of a reward. In the context of reward-related learning, dopamine also functions as a reward prediction error signal, that is, the degree to which the value of a reward is unexpected. According to this hypothesis proposed by Montague, Dayan, and Sejnowski, rewards that are expected do not produce a second phasic dopamine response in certain dopaminergic cells, but rewards that are unexpected, or greater than expected, produce a short-lasting increase in synaptic dopamine, whereas the omission of an expected reward actually causes dopamine release to drop below its background level.
That's neurodiversity and the social model of disability in a nutshell. We've defined a very narrow set of neurotypes as normal and treat any divergence from it as a disorder. We've additionally structured society in such a way that only this very narrow set is accommodated and provided affordances, making these disorders disabling to those "suffering" from it.
It's worth remembering that ADHD drugs can be an affordance even if we accept a social model of disability and a neurodiverse view of humanity. But the systems we have built drastically exaggerate the degree to which ADHD is "inherently" disabling, e.g. not opening your mail can land you in prison. Yes of course there's more to that than it just being "mail" but the mechanism itself is more dangerous to someone with ADHD traits than someone without them.
The same goes for autism by the way: arguably there are many benefits to autistic traits (which seems odd to explain on a site like this when for the longest time programmers online used to joke that we're all autistic and when the "aspie supremacist movement" is literally a thing) but at the same time it can be extremely disabling simply due to "how we do things", e.g. having to use the phone to book an appointment or being in a noisy office full of other people in order to get paid.
It's interesting to consider not only what we could do to provide affordances and accommodations more equitably but also who else would benefit from this as a kind of inverse collateral damage.
I feel adhd is only a diagnosis beacause society demands to much attention/focus; I've once told my therapist if flying was required to be part of the society my diagnosis would be unwinged
No it's not. It's a disability with very serious consequences for the lifespan of people affected. Please don't repeat this pointless pseudoscientific bs. This link contains a good starting point to understanding what science knows about it.
Men have shorter lifespan's than women largely due to testosterone, but that doesn't mean men having testosterone is evolutionarily maladaptive.
I eye some risks people with ADHD have, like higher risk for STIs. Sure, Russel Barkley things people with ADHD getting STI's makes them "disabled", but evolution gives a bit two thumbs up to people with ADHD having unprotected sex. Barkley then brags treating ADHD will reduce STIs, by you know, reducing the amount of unprotected sex with multiple partners that they're having. If anything listening to Barkley's advice is likely to make the average person less reproductively successful.
I don't know, I don't like Barkley and his pro-pharma fan club. It's correct that medicating people with ADHD will profoundly change their behaviour. But I don't see any reason to call the prior way people ADHD people behaved as "disordered" and "a disability" and the new way they behave on stimulants to be curing them of a horrible disease or whatever. That description is not scientific - it's subjective what we do or don't consider a disability or disorder. If you prefer life on addy, good for you, keep using addy. I find the entire way we decide to describe behavioural and neurological differences as disabilities and disorders to just be thinly veiled bigotry often taking the form of self-hatred.
> It's a disability with very serious consequences for the lifespan of people affected.
I think this is the case for those with severe ADHD. They can't really function at all in modern society, it's a severe impediment.
Vast majority of ADHD (esp. adult adhd cases, where childhood symptoms were not obvious) are nothing like that. I think this is where the idea of it being a phenotype comes in, for the mild/moderate ADHD cases.
I mean, I'm sure it could be if it were a serious enough case, but the ADHD that I was diagnosed with is nothing more than the inability to do shit that I find boring. It's a career limiting inconvenience.
I find that 10mg of a Concerta derivative make me enjoy the positive aspects of my disorder -- ADHD inattentive type -- while preventing the negatives. I was already a working adult when I first tried medicating and it's been a life changing experience. I take one dose on a weekday morning when I have to concentrate on manual tasks and I skip the dose when I want to use more of my imagination for concept and idea gathering.
Outside of the dosage, seconding this! Also inattentive flavoured ADHD. 70mg Elvanse usually allows me to be a productive day to day person, skipping the dose on Saturdays is where I let myself freely roam the internet and tinker with new software, languages, systems, coming up with fiction, coming up with sketches for a TV show that will probably never see the light of day, etc. Sundays get a dose as normal but I use that for housework and the likes. I've been brushing up on Kubernetes most recently, I don't need it anywhere right now but who knows where it (or the concepts in and around it) will come up. Also it's kinda cool honestly :)
It's the best of both worlds.. as best as I have got it so far in 35 years anyway, not perfect, but it mostly works - I can earn enough to survive without having to actually forage in bushes, and I get to learn stuff that's interesting but not immediately useful for that all-natural dopamine fix.
The not immediately useful stuff often combines with future problems and becomes a "genius" solution, haha. If you ever want to be called a genius all you have to do is plug two seemingly separate things you know into each other.
While my Elvanse dose is merely half of yours it always seems to affect my nervous system for much too long, keeping me unable to sleep before 3am on weekdays on the average.
My partner tried a lot (and went trough weird other diagnosis) and found her solution in simple dextroamphetamine. It's a life changer for her and our relationship as well :) also very cheap as it's no protected substance.
Around here many are deemed to get ritalin first or other similarly weird substances which has way more side effects for some than good ol' amphetamine.
I was on Adderall for about 10 years, when I moved to Asia I discovered 'amphs are banned, so they put me on Ritalin. Holy mother of god how people tolerate that stuff is beyond me. Over the course of an hour, I'd oscillate between wanting to go to the gym, anger, and horny. Had to discontinue using it for fear I'd kill someone during the anger phase. I've tried many substanced but I gotta say... Ritalin is high on the list of weird drugs for me.
I never thought ADHD was evolutionary maladaptive, this is a condition which makes you more likely to blow off work and have unprotected sex. It's treated as a mental illness and disorder because those with it are less economically productive and experience more distress than most people.
> makes you more likely to […] have unprotected sex
As someone with ADD, I wish I could agree. Adding to that, ADD can also be reasonably economically productive if the field of work aligns with the requirements of the condition. IT usually happens to be one of them. Productive squirrel chasing, if you like. Just work on a different issue for a bit, learn something new, etc.
Right now the strongest selection pressure on humans is for ppl who have “irresponsible” unprotected sex. Sensible people who use birth control are failing to reproduce.
A friend of mine runs a number of London psych clinics, focusing on ADHD. In a recent discussion we compared ADHD to the explorers and inventors throughout history. The aversion to the status quo and the appetite for risk are not always good for the individual but the rewards for the group may be huge if there is success.
This has always been my theory (as someone with the condition). The human species has benefitted greatly from having 3-4% of us being constantly restless and always NEEDING to know "what new thing can we do NOW!!"
You wouldnt need full BP or Schizophrenia to justify this -- if partial traits to partial degrees confer advantage, then the full constellation of them may be dysfunctional in an individual but worth preserving for net benefits. Evolution does not operate at the level of individuals, so most in practice, are often dysfunctional in many respects.
As for schizophrenia, see it is an exageration of rule-seeking and pattern-seeking behaviour, an over-imparting of consciousness and intention to the world, a (disregulated) sense of significance. But each of these are vital for survival and procreation in less extreme degrees.
As for BP, hypomania seems plainly adaptive in some cases (eg., esp. having sex a lot, working a lot, ...); and "hypo-depression" likewise (eg., low opporunitites for winter work, retreating, conserving, less risk takign, etc.).
It also seems adaptive that we would swing between these, so we can better explore the mood-space of motivation.
Someone posted an article a while ago that claimed the ratio of people with ADHD, autism, etc. lined up with Dunbar’s number (the theoretical preferred size of a social group) so that there would be about one individual per group with these traits. The article then went on to theorize that this was an evolutionary adaptation against total conformity. Even if everyone else doesn’t see the landslide in the distance the one weirdo might.
I can’t find the article after searching on hn.algolia.com but IIRC there was no real evidence for this, it was just a theory.
Don't know much about BPD, know a little more about schizophrenia. The genes that make you predisposed to schizophrenia seem to positively impact creativity and certain types of creative output. A gene doesn't necessarily have to have a good outcome for everybody with that gene, so long as it results in enough good outcome to make up for it.
I think of this with homosexuality. What is the possible evolutionary advantage to homosexuality? Well there's lots of reasons why we would want humans to be attracted to both men and women, so they're reproduce, and it's not hard to see how genes that cause that could make people gay.
Readit News
Eventually, I got slightly better at sitting still and "focusing". I would (and still do) fidget like crazy, either pen spinning, tapping my feet, rocking back and forth while "focusing". Focusing was just me quickly switching between what I was supposed to be doing and anything else, back and forth.
The upside is now I am basically "immune" to distractions, I can always reply to slack/my girlfriend/whatsapp messages/alerts/PR feedback/emails/questions and then go back to what I was doing 5 seconds ago without any issues. I've probably switched between this comment box and coding 20 times at this point.
I tried getting an adult diagnosis in the UK to see if maybe "proper drugs" would be helpful, but was just told politely to fuck off by the GP. The reasoning was that I have a job in tech, so even if I had ADHD, it's not bad enough to warrant any treatment. Lots of coffee and listening to "hardstyle" or any music with high BPM seems to help me focus.
If you're ever looking to chase that down again, having a successful career shouldn't preclude you from being "impaired" enough to be treated for ADHD, but you need to emphasize _how_ your life is negatively impacted to give the GP, Psychologist, or anyone else involved the justification they need to diagnose and treat you. (And if you already did this, well, maybe another doctor?)
When I was diagnosed my being relatively successful was definitely some points against, but really high level I was able to explain:
- That I had recently switched jobs, the previous behaviours _are_ impacting my work, and here's exactly how.
- Detailed some of the challenges I faced in my day-to-day life personally and how it was impacting my family.
- For questions where I am not particularly impaired, where possible I explained the coping strategies I use in order to, y'know, function, but obviously that this was still stressful and difficult for me.
The psychologist had no issue diagnosing me with ADHD and recommending my GP prescribe me medication. He was not surprised to hear that over a few decades I'd managed to develop one or two coping strategies, and the strategies I'd explained were actually consistent with an ADHD diagnosis.
Mind you, these were high functioning individuals. They found ways to use their bountiful reserves of energy to earn a lot of money. Maybe there are others that can't focus on anything for a long period - I don't know.
The difference between them and myself (apart from that energy) was that I can, with a struggle, force myself to focus on most things if I'm physically comfortable. That said, doing something I don't like is struggle, and I'll procrastinate like crazy. But for them, it seemed near impossible.
They solved the problem in the same way I do for regular things I don't like doing. They incorporated it into their daily routine. Repeating a routine, even something a simple as casting a fishing line (which I guess is not that simple to do well, now I think about it), brings it's own pleasures regardless of the task. For me it takes a few weeks to add something to my routine. For them, it seemed to take months or years. The self discipline they applied to keep at it until it became a routine they enjoyed for it's own sake, was amazing.
The problem is I have a hard time controlling what that focus will actually be on.
Dead Comment
People online assert a lot of things, such as "it's a dysfunction of dopamine pathways", "it's genetic", "it's a sort of autism", "it's a brain chemistry problem". But never anything that looked like a real definition backed by good science.
My own psychiatrist's diagnosis was a bunch of obvious questions that I couldn't answer honestly even if I tried. The conversation boils down to: "I have trouble concentrating and wonder if I have ADHD, I have [common symptoms backed by anecdotal evidence]. - OK, they have to affect your life severely enough to qualify. Do you think they are? - I guess, that's what I'm here to find out. - OK, let's try Ritalin." It was only helpful in that I needed to focus during a semester of studies and the stimulants did it.
It feels like I had a cough, got diagnosed with cough syndrome, and went through cough medications until they started helping the cough, and now I can describe myself as a cough syndrome sufferer. Where's the virus?
It is clearly defined and operationalised for medical diagnostic purposes.
https://www.aafp.org/dam/AAFP/documents/patient_care/adhd_to...
It's causes are understood to be a combination of genetic risk factors (its heritable and follows family trees), and environmental factors such as child abuse increase the odds of an ADHD diagnosis being made.
To waffle freely:
I believe it's lower than normal background levels of dopamine.
Obligatory disclaimer I am in no way a doctor or scientist. This is probably wrong. Pinches of salt all round. This is a theory I'm kicking around now and then but I don't have the knowledge to confirm/deny the hypothesis yet.
When a normal person tackles a regular task they'll get a little squirt of dopamine leading up to the task (anticipation) and then a corresponding signal when the task is done (I did the thing correctly, woohoo).[0]
When a normal person tackles a task and gets a better than expected result, they get a fresh squirt of dopamine upon completion (Oh wow, that went really well! I should consider doing this again!)
When someone with the ADHD-type brain wiring tackles a regular task they'll get the initial anticipation squirt, but upon completing the task they'll get a lesser amount (in dopamine language: that didn't go as well as I thought it would)
Compound that effect over $age years and you get someone with no real motivation to do anything, often distracted by random things that might be interesting, anxious, depression, imposter syndrome, all that good stuff - they rarely get a "I did good" signal, so nothing feels worth doing and they don't feel like they've had much success in life. Also might explain why a lot of ADHD folks have some sort of dopamine loop going on - alcohol, smoking, drugs, overeating, absolutely covering every meal in salt, etc. Something that brings up their background level of dopamine.
You do get positive effects from this - it's not all doom and gloom! - quick learners, jack of all trades, outside the box thinking, anything that might give a better dopamine response than the day to day routines
Might also explain all the "ADHD people were great as cavemen" stories that pop up now and then - nothing gives more dopamine than "holy fuck, I survived", the modern day doesn't really have many of those moments.
Feels like this would also explain why someone with ADHD can take stimulant medication and not bounce off the walls like a normal person would on the same medication - their background level of dopamine is being brought up to normal levels by the medication which in turn allows the rest of the system works as it does in normal people.
[0]: I actually found this theory while looking into AI stuff, haha: https://deepmind.google/discover/blog/dopamine-and-temporal-...
The quick summary from https://en.wikipedia.org/wiki/Dopamine
> Within the brain, dopamine functions partly as a global reward signal. An initial dopamine response to a rewarding stimulus encodes information about the salience, value, and context of a reward. In the context of reward-related learning, dopamine also functions as a reward prediction error signal, that is, the degree to which the value of a reward is unexpected. According to this hypothesis proposed by Montague, Dayan, and Sejnowski, rewards that are expected do not produce a second phasic dopamine response in certain dopaminergic cells, but rewards that are unexpected, or greater than expected, produce a short-lasting increase in synaptic dopamine, whereas the omission of an expected reward actually causes dopamine release to drop below its background level.
It's worth remembering that ADHD drugs can be an affordance even if we accept a social model of disability and a neurodiverse view of humanity. But the systems we have built drastically exaggerate the degree to which ADHD is "inherently" disabling, e.g. not opening your mail can land you in prison. Yes of course there's more to that than it just being "mail" but the mechanism itself is more dangerous to someone with ADHD traits than someone without them.
The same goes for autism by the way: arguably there are many benefits to autistic traits (which seems odd to explain on a site like this when for the longest time programmers online used to joke that we're all autistic and when the "aspie supremacist movement" is literally a thing) but at the same time it can be extremely disabling simply due to "how we do things", e.g. having to use the phone to book an appointment or being in a noisy office full of other people in order to get paid.
It's interesting to consider not only what we could do to provide affordances and accommodations more equitably but also who else would benefit from this as a kind of inverse collateral damage.
https://www.sciencedirect.com/science/article/pii/S014976342...
I eye some risks people with ADHD have, like higher risk for STIs. Sure, Russel Barkley things people with ADHD getting STI's makes them "disabled", but evolution gives a bit two thumbs up to people with ADHD having unprotected sex. Barkley then brags treating ADHD will reduce STIs, by you know, reducing the amount of unprotected sex with multiple partners that they're having. If anything listening to Barkley's advice is likely to make the average person less reproductively successful.
I don't know, I don't like Barkley and his pro-pharma fan club. It's correct that medicating people with ADHD will profoundly change their behaviour. But I don't see any reason to call the prior way people ADHD people behaved as "disordered" and "a disability" and the new way they behave on stimulants to be curing them of a horrible disease or whatever. That description is not scientific - it's subjective what we do or don't consider a disability or disorder. If you prefer life on addy, good for you, keep using addy. I find the entire way we decide to describe behavioural and neurological differences as disabilities and disorders to just be thinly veiled bigotry often taking the form of self-hatred.
I think this is the case for those with severe ADHD. They can't really function at all in modern society, it's a severe impediment.
Vast majority of ADHD (esp. adult adhd cases, where childhood symptoms were not obvious) are nothing like that. I think this is where the idea of it being a phenotype comes in, for the mild/moderate ADHD cases.
It's the best of both worlds.. as best as I have got it so far in 35 years anyway, not perfect, but it mostly works - I can earn enough to survive without having to actually forage in bushes, and I get to learn stuff that's interesting but not immediately useful for that all-natural dopamine fix.
The not immediately useful stuff often combines with future problems and becomes a "genius" solution, haha. If you ever want to be called a genius all you have to do is plug two seemingly separate things you know into each other.
While my Elvanse dose is merely half of yours it always seems to affect my nervous system for much too long, keeping me unable to sleep before 3am on weekdays on the average.
Around here many are deemed to get ritalin first or other similarly weird substances which has way more side effects for some than good ol' amphetamine.
As someone with ADD, I wish I could agree. Adding to that, ADD can also be reasonably economically productive if the field of work aligns with the requirements of the condition. IT usually happens to be one of them. Productive squirrel chasing, if you like. Just work on a different issue for a bit, learn something new, etc.
https://www.youtube.com/watch?v=ORq8VNIjDRA
there are some strong suggestions that those traits have been selected against quite a few times.
As for schizophrenia, see it is an exageration of rule-seeking and pattern-seeking behaviour, an over-imparting of consciousness and intention to the world, a (disregulated) sense of significance. But each of these are vital for survival and procreation in less extreme degrees.
As for BP, hypomania seems plainly adaptive in some cases (eg., esp. having sex a lot, working a lot, ...); and "hypo-depression" likewise (eg., low opporunitites for winter work, retreating, conserving, less risk takign, etc.).
It also seems adaptive that we would swing between these, so we can better explore the mood-space of motivation.
You just extremize that and you get disfunction
I can’t find the article after searching on hn.algolia.com but IIRC there was no real evidence for this, it was just a theory.
I think of this with homosexuality. What is the possible evolutionary advantage to homosexuality? Well there's lots of reasons why we would want humans to be attracted to both men and women, so they're reproduce, and it's not hard to see how genes that cause that could make people gay.