Theory on evolution

Post Reply New Topic

Take a closer look at the teenage girls who actually make up teen pregnancy statistics. Then take a closer look at the women on this forum.

That ASmom and her three NT children topic

The youngest is ADD, but NT personality!

I hope for an ASpie grandchild. And for him/her to have children.

I think it is a mistake to confuse genetic diversity with evolution. The former is a propogation of various traits and mutations among individuals of a particular species. Everything from eye colour to (possibly) autistic characteristics has its origin in the genetic diversity of the species.

Evolution, on the other hand, is the macro-level process by which a particularly beneficial characteristics becomes dominant across a species (or a group sufficiently distinct to merit classification as a subspecies). Our cognitive capacity is an evolutionary development that separates us from the other primates. Opposable thumbs are an evolutionary characteristic that separates the primates from other families of mammals.

Over time, genetic diversity, reproductive fitness and environmental suitability will allow certain characteristics to flourish, and cause others to die out. But the timeframes involved are thousands of generations.

Small changes add up. That's the point. What starts as simple diversity of traits in one species ends up as multiple species. Diversity is also very important to natural selection, because a nondiverse species is vulnerable to all sorts of threats. (Example: Cheetahs. Huge problem with lack of genetic diversity; they may die out thanks to a genetic bottleneck that left them with a small gene pool.)

People mistake evolution for a process that makes species better in some sort of ladder, one step better than the next. Not so much. Evolution is diversification. Individual species specialize into ecological niches. It doesn't matter how smart you are or how dextrous your hands are if you can't reproduce and compete with those around you for resources. A "better" species, as far as natural selection is concerned, is not a more complex one but the one that best fits the environment.

So, not only are we not the "next step" in evolution... there is no next step in evolution.

So you are arguing that the traits are novel and beneficial enough that they are persisting against selection(of course they are), yet routinely match up creating a person called autistic? Either that or you think the traits are mutations which are orders of magnitude higher than other mutations. Or something.

Maybe you think that aspies that do find a mate contribute more than typical numbers of children to the gene pool? Or that the clade is relatively recent, and that it will rapidly vanish?

I have to agree that Autism is selected against. But I have to argue that the phenomenon persists(and has for millennia). Perhaps not always linear, but as a combinant result of human mating.

Like a bird with a third wing being born 1 out of 100 times. That birds DNA never survives, but you keep finding three winged birds. Why?

Why do beneficially traited humans keep pairing up to make autistic babies?

The genetics for autism benefit the population as a whole. (I explained this more fully in an earlier post--check the first page.)

RE: Autists are normal, more intelligent...etc.
About 80-90% of autistic adults are currently unemployed. It can even exceed 90%.

RE: Autism genes benefit the population.
Trisomy? Myopia? Schizophrenia? Progeria? Cancer? Dwarfism? ...

RE: Children/parents diagnosed with Asperger's syndrome.
Nothing to be proud of. I'm not expecting parents to display remorses or feel ashamed, especially when they didn't know what they were doing, but don't push it.

RE: Stupid people who have 8 kids will carry our spies forward.
I have not seen couples suffering from mental retardation with 8 children. Most humans are average, intelligence-wise, so within the norm.

RE: Bigger demand for the skills of Aspies in the future.
Collecting Lego bricks?

Quite aware of that. What I was asking Orwell is why those traits dont persist as individual traits in humanity. Rather, they seem to cause people to pair up and produce autistics. Its almost as if autism is being selected FOR not against, but once its produced it proves less viable.

Thanks Orwell, you have in your succinct manner saved me from a lengthy tirade. What interests me; why do so many with aspegers have this delusion?

I wonder the same. See my thread on Dropping the attitude, and maybe the lock one "and with this I may crucify myself..." I ask the same, got mixed responses. Or to be more precise I asked why so many with AS think they are superior.

Even Temple Grandin argues that population genetics would not benefit from NOT having autistic genes floatin about. I agree. Considering the larger picture of evolution is not a discrete concept... yet it's very hard not to think discretely about it--meaning to consider the individuals individually comes naturally.

Species wide it is in the genome. It matters not if an autistic person reproduces, if any do, the genes are carried forward. When the right mix comes along, another autist is born.

The Broader Autism Phenotype is useful, half aspies with sub clinical traits. They are the ones whos matings produce autists, so the question is, are they spreading their genes beyond the BAP boundries?

They are more common in Science, Technology, and Education. All of these give them something of a closed playground, and one that others wish to join. So they carry the autism genes, and are attractive to the better population. Autism will spread.

A followup on Aspergers type subjects said they went on to lead normal lives, which would include reproduction.

Autism at a disability level will of course reduce reproduction. It does not rule it out. Many have found a place in the world where their lacks are hidden, and their talents profit them.

While looks and social skills do seem to be first pick for reproduction, the good ones are chosen early, and in the declining pool of possible mates, having a good income, a home, does overcome a lack of looks and social skill.

The other choices also have their problems, the athelete and the beauty are the makings of, Married, With Children. Al and Peg were top choices in their high school, star football player and cheerleader.

The single mother is a recent cultural icon, The effects of that pattern are yet to be seen.

The better male workers who have high flying careers, are also the ones who die at 43 of a heart attack, and there are a lot of them. They might be insured for a few years wages, but they leave a wife and children who will be house poor. Single parent, with much higher overhead.

Another model is raising the children, sending them to the university, then divorcing, and marrying some twenty year old trophy younger than your daughter.

A lot of marriage does not produce children or last two years, and many have done that five times.

While autism does breed autism, there are a lot of other things that also breed increased versions, which keeps prisons and mental hospitals full.

Broader Autism Phenotype is one of the more stable groups, Educated, working in Science, Technology, and the Arts. In breeding may produce some less functional types, but they are also well set for out breeding, which spreads the genome.

BAP could also have better employment, they do not make the high incomes of the very social in business, but that teaching job comes with a paycheck and not with a layoff notice.

NT employment, construction, production worker, lower office, have all seen major job cuts, but there is a teacher shortage, the same for nurses, lab workers, medical records, which are growing fields.

So in many ways they might have the more stable jobs, incomes, families, and do a better job of raising the next generation. BAP would also be the most adaptive in raising an aspie who did find a place in life, if your parents are university professors, you will get an education. Being born into a blue collar family, an aspie would have less chance of using their talents and masking their differance.

I would think that the BAP is spreading, more demand for knowledge workers, and what jobs still exist for the uneducated, are being sent abroad or taken by immigrants. This will have much more impact on the social NT model of survival, the rough end of life is falling on the unemployed, an NT group, Their lack of knowledge, skills, focus, is no longer needed, and if the economy picks up, they will not be the workers in demand.

We now have a group larger than the BAP that is unemployed, has had the house foreclosed, and are living with relatives, or in tent cities under bridges. This does not lead to reproductive sucess.

Social skills are only one factor in evolution. Those who lacked them and lived in a hut in the country, missed the Black Death. Those who were rejected for military service missed the glory charge into the machine guns. WWI sent groups by district, and in many, every man died. The Village Aspie was still around.

Traits like not minding eating the same food every meal, like oatmeal, means that oat eaters survived the famine.

When the Vikings came, they slaughtered everyone along the main roads and in the towns, the non social living in the forests survived.

The tecnological who made the iron weapons, were not sent to the front, they stayed home at the forge, making more weapons, and some good money. Vulcan was lame, had a club foot, iron workers were the disabled.

In a world of free men, one group was not, boys with autistic traits were sold. They became the slaves of a master who could hang them for running away, and do anything else he thought of. They were apprentices, bought at six or seven, and bound for seven years of labor. They had no life but to learn one trade, and after a second seven years, when the could chose their master and work for wages, they could stand to be admitted to the guild, and become a master.

Boring life, single focus, fed like an animal, fourteen years, then become a master, and at 21, be allowed to marry a masters daughter. About one in a hundred boys were sold to the guilds.

On the female side, in the old days if you got a girl in trouble, you married her, as the priest, sheriff, and her dad with a shotgun said. Girls were chatel, if you had done the same his sheep, you would be hung.

Autism is still around because it has some strong survival traits. I would say it is a growing segment of the gene pool.

999 out of 1000 times, yes. The 1000th time, you get Einstein. It's worth it.


Trisomy is usually not inherited. It happens when the chromosomes replicate themselves.

Myopia is not severe enough to be selected against in any environment that does not depend on extremely acute vision. Humans are already half-blind as it is, and we haven't needed everyone to have very good eyesight for hundreds of years now.

Schizophrenia is associated with creativity, invention, and art. In small doses, these genes benefit a population, similarly to autism.

Progeria has several variations, most of which are due to new mutations, not heritable.

Cancer isn't one illness; it's multiple illnesses. Most of these are not heritable either. Besides, cancer almost always affects the individual after the reproductive years are nearly or completely over.

Dwarfism also refers to quite a lot of conditions, most of which do not reduce the lifespan or the ability to reproduce. Most kinds are also the result of a new mutation, though the most common kind can be inherited. Between the new mutations and the fact that most kinds of dwarfism do not affect intelligence, lifespan, or the ability to have children, it's no surprise there are plenty of little people around.

Well, at this point I have to bring up the fact that autism is not a discrete condition like Down's Syndrome or a third wing on a bird. When certain traits exist in certain intensities, it is termed autism or Asperger's. Engineers (even non-autistic engineers) disproportionately produce autistic children when they reproduce. Note however that engineers, mathematicians, programmers etc also tend to have fewer children (on average) than the general population. Callista's argument can give a partial answer to why autistic traits might persist, but I would question how much standard population genetics can apply to humans- my very normal sister would gain no Darwinian advantage from me becoming a highly-paid engineer. Our social structure doesn't really work like that anymore.

The causes of autism appear to be genetic, but are still unknown. Natural selection (really sexual selection, as modern civilization has rendered natural selection moot in our species) would not generally favor either autistics or individuals (like my parents) with sub-threshold autistic traits. I mentioned before that older fathers are more likely to have autistic children than younger fathers, so this could be a contributing factor.

Historically, human socieities have tended to function so that benefit to a member of a familial group can often result in reproductive benefits for other members of the familial group. If this can be claimed to no longer be true with respect to a particular population, that population's genetic heritage will none the less be one where such transferrable benefits have featured historically, and so the current gene pool will likely reflect that rather than the more novel situation of non-transferrable reproductive benefits.

However, aside from transferrable familial advantage, there is also heterozygote advantage (such as seen with alleles for sickle cell, and such as presumably has occured historically in respect of tay-sachs).


Natural selection is not moot. Less than a century ago, there was a massive culling due to influenza. The time since that is in evolutionary terms negliable, and we have no assurances as to how long it will be before we are struck by another such epidemic. Meanwhile, at the species level (rather than at the "selected societies" level), maleria continues to be an important selection mechanism in areas where it is endemnic. AIDS is also endemnic to many places/populations, and people vary in their vulnerability to infection. ..etc...

In so called "first-world" nations, there are no doubt many selective pressures if you stop and consider. Take for instance the problems with hormones leaching from plastics and effecting reproductive fitness (for instance lowering sperm counts in males). That everyone is equally vulnerable to damage to their reproductive functioning from such polluting hormones is highly unlikely; people who are more resistent to negative effects on reproductive functioning from hormones commonly leaching into our environment from modern manufactured consumables, have a reproductive advantage over those who are more vulnerable to such reproductive disruption. As these hormones will probably over the future be present in ever higher levels, this selective pressure is likely to become more significant over time. ...etc...

I believe that genes for autism have always been around. I think when life was simpler, such as in hunter gatherer society, it may not have been as much of a problem. Societies were smaller and people stayed near their family units anyway. Someone who was good at skilled work or hunting would have been tolerated even if they didnt fit into the tribe so well socially. They would have also been protected by their family group.

But now our society is more socially complex so I think it is harder and people with autistic traits stand out more. Also people are expected to move away from their families to become an adult. In more traditional societies, a child's parents pretty much arrange their adult life: the arranged marriage, the family business... now that isnt happening anymore guess who stands out like a sore thumb.