You may care to read my research article at Aulis online, Humankind's Origins, entitled (by the publisher) 'More light on Neanderthals'. Certain ailments or adaptations occur more often among people born at times of less solar activity and others among people born at times of more. Autism tallies with less activity, which is typical of ice ages, so autism and tallying conditions may be adaptations to these. In ice ages there is less greenery, so people are scarcer and have to be able to get on without socializing, but this may not mean that the number of sunspots at birth shows whether or not a person is autistic. Some people have a greater inherited bias towards autism than others in being more nordic so may be autistic in spite of, not because of, the level of solar activity. The level is not coercive but merely sensed as a guide to the climate. On a day of more drizzle, more people are likely to wear raincoats, but even during a thunderstorm some people may prefer not to.