It is my contention that Atheism defined for this purpose herein as the "absence of belief in gods" is the natural state of humankind, as I presume it is for all natural life on the planet. A baby is born into this world pure and unadulterated, and only becomes a Theist, if it becomes a Theist at all, through either family indoctrination, or as a result of the effects of social osmosis from the wider community or peer group or through some other earthly, natural cause in contradistinction to some supernatural cause.
If the above is the case then couldn't it be asserted that Atheists are Natural, and Theists Unnatural. We are Pure, and Unadulterated in that respect whereas Theists are Impure?!