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Autism and Evolution

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Re: Autism and Evolution

#11

Post by hannob »

adsfqwop wrote: post #4

I don't quite buy that autism will be shown to be genetic. I think it's an environmental factor. The rate of increase in autism is pretty much exponential: http://www.nature.com/news/2011/111102/full/479022a/box/1.ht... Now that's a very scary chart if you start to project that curve into the future. Here's another one. Not saying this is the cause, but it is a cause for concern. We have many similar patterns of envi…

> I don't quite buy that autism will be shown to be genetic. I think it's an environmental factor. The rate of increase in autism is pretty much exponential:

You're confusing increase in diagnosis versus increase in autism. This confusion is the whole basis of the "autism epidemic" claim.

Re: Autism and Evolution

#12

Post by QuotedForTruth »

adsfqwop wrote: post #4

I don't quite buy that autism will be shown to be genetic. I think it's an environmental factor. The rate of increase in autism is pretty much exponential: http://www.nature.com/news/2011/111102/full/479022a/box/1.ht... Now that's a very scary chart if you start to project that curve into the future. Here's another one. Not saying this is the cause, but it is a cause for concern. We have many similar patterns of envi…

Another possible explanation for such a rise that I have seen repeatedly given is that the methods and basis for diagnosis changed in the early 90s.

http://www.forbes.com/sites/tarahaelle/2015/01/05/majority-o...

Its also discussed here on Fresh Air by the author of a book on Autism called Neurotribes.

" But because no one really explained to parents exactly what had happened - that the diagnosis had been completely rewritten - that, you know, autism by the end of the 1980s and the early 1990s was not your grandfather's autism, you could say. It was much more broadly defined because no one ever explained to the lay public what had happened with the diagnosis. When the numbers started going up, parents very understandably became very alarmed. And the media was sort of blindsided by the sudden spike in diagnoses."

http://www.npr.org/2016/09/09/493148713/neurotribes-examines...

Re: Autism and Evolution

#13

Post by kijin »

3pt14159 wrote: post #8
adsfqwop wrote: post #4

I don't quite buy that autism will be shown to be genetic. I think it's an environmental factor. The rate of increase in autism is pretty much exponential: http://www.nature.com/news/2011/111102/full/479022a/box/1.ht... Now that's a very scary chart if you start to project that curve into the future. Here's another one. Not saying this is the cause, but it is a cause for concern. We have many similar patterns of envi…

My cousin had debilitating autism that was greatly diminished by removing wheat germ from his diet, so I partially buy the environmental take, but on the other hand it is a disease that is correlated with parental IQ, where a higher IQ leads to more likely incidence of autism. I don't think it's a coincidence that the rise of co-sexed secondary education and finer grained sorting with institutions like Harvard and MI…

Since this thread is about evolution, we might even say that the evolutionary pressures we currently face in the developed world actually favor mild variants of ASD.

It might be because some ASD traits help people become more successful in the information economy. Asperger's people often thrive in well-paid occupations such as programming and data analysis where spontaneous social interaction is widely acknowledged to hurt productivity.

Or it might just be a side effect of a society that places a lot of emphasis on intelligence, making it more likely for a person with high IQ to seek a mate with similarly high IQ. The more smart people "inbreed" among themselves, the more ASD cases we will naturally see.

In either case, since evolution is whack-a-mole, this will lead to not only mild ASD but also more cases of severe autism if they are caused by the same set of genes.

Re: Autism and Evolution

#14

Post by i14ng »

adsfqwop wrote: post #4

I don't quite buy that autism will be shown to be genetic. I think it's an environmental factor. The rate of increase in autism is pretty much exponential: http://www.nature.com/news/2011/111102/full/479022a/box/1.ht... Now that's a very scary chart if you start to project that curve into the future. Here's another one. Not saying this is the cause, but it is a cause for concern. We have many similar patterns of envi…

When the autism diagnostic criteria were broadened in the DSM, the people making that change predicted that we would see this rise in diagnostic rates. That was the intent, to help a broader range of people. It's played out slowly as clinicians and schools were retrained. There's also been an increasing incentive to diagnose as autism in addition to intellectual disability when possible, because insurance companies and schools will do a lot more if it's labeled autism.

So we've seen that shift. The diagnostic criteria changed a lot, not just a little, over time.

By coincidence, Wakefield launched his fraudulent crap about vaccines a few years after the criteria were broadened, and that became the popular explanation rather than the fact that the criteria changed. Belief in his BS is perhaps fading but it's still around.

The "epidemic" was predicted and an intentional outcome of the DSM criteria change, though.

If you hang out with a bunch of families with autistic kids, it's very obviously inherited in a large fraction of cases, because the kids are so much like their parents.

Another large fraction is likely genetic in the sense of "de novo" mutation, rather than inherited genes. There's likely also a group of environmental cases, mostly prenatal environmental factors.

Because social function depends on many coordinated aspects of human cognition, any condition that has a fairly global effect on the brain can create traits meeting the autism diagnostic criteria. The criteria are very broad, with many different ways to meet them.

It's important to realize that autism is a broad category, not a single condition, and no proposed single gene or environmental factor ever seems to relate to more than a few percent of cases. https://intellectualizing.net/2013/12/17/book-rethinking-aut...

Some of those causes could well be new to the modern world, but the changing diagnostic criteria do explain most of the expansion in diagnoses already, so there isn't a lot of evidence that we need to be looking for something novel to explain the increased diagnoses.

Re: Autism and Evolution

#15

Post by xutopia »

adsfqwop wrote: post #4

I don't quite buy that autism will be shown to be genetic. I think it's an environmental factor. The rate of increase in autism is pretty much exponential: http://www.nature.com/news/2011/111102/full/479022a/box/1.ht... Now that's a very scary chart if you start to project that curve into the future. Here's another one. Not saying this is the cause, but it is a cause for concern. We have many similar patterns of envi…

What if the markers are recessive and the social fabric today means more people with the recessive genes procreate?

Re: Autism and Evolution

#16

Post by euyyn »

i14ng wrote: post #14
adsfqwop wrote: post #4

I don't quite buy that autism will be shown to be genetic. I think it's an environmental factor. The rate of increase in autism is pretty much exponential: http://www.nature.com/news/2011/111102/full/479022a/box/1.ht... Now that's a very scary chart if you start to project that curve into the future. Here's another one. Not saying this is the cause, but it is a cause for concern. We have many similar patterns of envi…

When the autism diagnostic criteria were broadened in the DSM, the people making that change predicted that we would see this rise in diagnostic rates. That was the intent, to help a broader range of people. It's played out slowly as clinicians and schools were retrained. There's also been an increasing incentive to diagnose as autism in addition to intellectual disability when possible, because insurance companies a…

Can you give more details on the "some of them are obviously inherited, because the kids are so much like the parents" part? Kids everywhere are so much like their parents, so the reasoning, as written, is nonsense.

Re: Autism and Evolution

#19

Post by T0T0R0 »

Cozumel wrote: post #2

Similar: https://www.sciencedaily.com/releases/2016/08/160815064944.h... Schizophrenia emerged after humans diverged from Neanderthals

The incredible part about that detail would be that in any other animal much of Schizophrenia's symptoms would be subclinical, in that language and socialization expresses most of Schizophrenia's detriments.

The paper is really about emergence and transmission of the disorder, and not so much about why humans find faults in those afflicted by it. But consider solitary animals, or apex predators. That they'd be schizophrenic, and construct distorted understandings of the world around them probably wouldn't matter, as long as they manage to hunt for food and produce offspring. No one would care about what a bear thinks of the origin of the universe, or how realistic its outlook of its own future is.

I realize that Schizophrenia has other debilitating effects, but it also affects people in varying degrees.

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