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.
"The almost universal distribution of the trend towards a gradual decrease of the brain size after the Perigord-Aurgnacian subphase seems to suggest that it may belong to the category of changes: new anagenetic or ecosensitive. In the first case, i.e. a new anagenetic evolutionary trend, a complete reversal of the direction of natural selection should be assumed. Otherwise speaking, the small brained individuals have been favoured against the big-brained ones. However, such an explanation can not be easily accepted since it would be in distinct contradiction with the following facts: the cultural evolution has been proceeding non stop and is even conspicuously accelerated in the last millennias; there is a lack of dependence on the mode of life which might include the possible selective agents. (Wiercinski, Andrzej (1979) Has the brain size decreased since the upper paleolithic. Bulletins et memoires 13 (6) (4): pp. 425)