[ExI] addiction and alcohol

[Stathis Papaioannou]

On 30 April 2015 at 14:50, Keith Henson <hkeithhenson at gmail.com> wrote:
> On Mon, Apr 6, 2015 at 9:34 AM, Keith Henson <hkeithhenson at gmail.com> wrote:
>> On Mon, Apr 6, 2015 at 5:00 AM,  William Flynn Wallace
>> <foozler83 at gmail.com> wrote:
> snip
>
>>> Stathis Papaioannou wrote:
>>
>>> Evolution has not had long enough to act on addiction, which is a
>>> maladaptive hijacking of a physiological system.
>>
>> Let me supply a hint.  Every characteristic in living things is the
>> result of positive selection unless it is a side effect of something
>> that is (or was) under positive selection.
>>
>> Which is the capacity to be addicted?  Direct or a side effect?
>
> It was either to easy a question or too hard.
>
> Addition is a side effect of substances that activate the brain reward
> system by being similar to natural brain reward chemicals.  Given the
> relatively low percentage of the population that can be addicted at
> all, makes it likely that the ability to be addicted is under
> selection.
>
> Alcohol is another substance that has been with some groups of people
> long enough to have weeded most of the genes that make people
> susceptible.  Peoples with no history of exposure to alcohol do poorly
> when it becomes available.
>
> It would be politically incorrect to study the subject, however
> informal information makes a case that the drop in some groups
> incidence of addiction to alcohol can be accounted for by changes in
> gene frequencies over the last few generations.

Getting old and weak is maladaptive, but evolution has not eliminated
ageing because people reproduce before age affects their ability to do
so. It could be the same with addiction.


-- 
Stathis Papaioannou