Is Autism Part Of The Evolutionary Process Of Homo Sapiens?

Genesis

To begin, Autism is a neurological developmental disorder. It has been found in the fossil record of humans dating back to the Mousterian period (110,000 BC). This development does not mean that these individuals were related to those diagnosed with Autism now; it means that Autism is an intrinsic part of the evolutionary process.

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The frequency of this gene has increased over time because those who had it survived longer than those without it. The ones who survived were able to pass their “autistic” genes onto their offspring. There are other factors that contribute to this increase as well: medical advances and better diagnostic techniques lead to an increased rate of diagnosis compared to times past when individuals exhibiting autistic traits may have escaped detection fallen under different diagnostic categories.

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In archaeology, though, finding a fossil with obvious signs of Autism is not unheard of. In fact, some believe that individuals with Autism have been underdiagnosed in the past because of poor interpretation on behalf of medical professionals.

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In time, however, this “under-diagnosis” becomes less and less likely to occur. Evidence suggests that Autism was a planned adaptation for Homo sapiens originally. Oftentimes these individuals did not find mates and spent their lives among themselves until they died. For modern humans, rates of Autism are estimated at over 1% of the population–a far cry from the 0.2% found in ancient populations across all historical periods. Not only does its presence indicate high genetic variability, but it shows us how adaptable the human brain is, even in its disorders.

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One theory suggests that Autism is essentially a discovery of modern psychology. The way it manifests itself today may be different from how it did so in the past because social interaction was far more limited than it is now. In fact, Autism wasn’t added to the Diagnostic and Statistical Manual of Mental Disorders until 1980–seven years after homosexuality was removed from it. It’s clear from this example that our views on what does and does not constitute a disorder have changed over time since both homosexuality and Autism are biologically-based conditions that some societies consider undesirable or faulty.

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Learning about these concepts can help us understand why Autism exists while also learning more about ourselves. We aspire to learn how we became who we are today. It’s only natural that one way to do this is by looking into the past. Even if it doesn’t always mean that individuals with Autism were diagnosed in our ancestors’ time, Autism has been part of every living thing–even Homo Sapiens.

References:

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“Autistic Disorder.” Autistic Disorder Fact Sheet NINDS, 14 June 2014, http://www.ninds.nih.gov/disorders/autism/detail_autism.htm.

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