Human evolution theory utilizing concepts of neoteny & female sexual selection
An etiology of neuropsychological disorders such as autism and dyslexia, and the origin of left handedness.
[citations removed] [Vermont 1981-1985] "In our sample of alcoholic men: (a) significantly more LH men were first-born; (b) significantly more men either LH or having a LH first-degree relative had an alcoholic father; (c) the RH men showed a slightly increased frequency of having an alcoholic mother or maternal grandfather; and (d) the RH men, particularly those having a maternal family history of alcoholism, were born more frequently than expected in summer and fall. This report indicates that the LH individuals in our sample were hospitalized more frequently than expected during October, a finding possibly related to Irwin's hypothesis. ... Twenty-four percent (10/42) of the LH individuals (seven of 32 men and three of 10 women) were hospitalized during October, vs 7% (19/278) of the RH individuals. .... The RH admissions were distributed equally throughout the year (7-10% per month; expected value, 8%). Stated another way, 13% of the sample were LH and so the expected percent of LH admissions during any month is also 13%. During October, however, 34% (10/29) of the admissions were LH, vs 11% (32/291) during the rest of the year (P<0.005, as above). The only other month with an excess of LH admissions was May, during which 23% (6/26) of the admissions were LH." London, WP (1986) Month of hospitalization of left-handed substance abusers. Neuropsychologia 24: 455)