This will be a really brief treatment of what, for me, being the parent of an adolescent daughter, is a very hard film to watch. Sure...some of the performances are sub-par; but, the pain that is the theme of the film goes right to the heart of a major element of human experience that has been illuminated by evolutionary paychology.
The central reference here is work by Draper & Harpending, focusing on the variability in reproductive behavior engaged in by women/adolescent females as a consequence of the parental care they were exposed to in their "life histories." In the absence of a competent adult male in the development of a female (whether biological father or not), it is more probable that an adolescent female will experience "early menarche, first sexual intercourse, first pregnancy, and shorter duration of first marriage". Additionally, parental separation during adolescence was "the strongest predictor of number of sex partners." Pay attention here. It's not just the social behavior of female adolescents that is affected by the father-absent variable.....it is the physiological behavior as well - early menarch. The body is "saying", "best prepare for sexual activity early." Why?
The answer appears to be that the lack of male parental provisioning signaled by the absence of a stable male father figure (not necessarily the biological father), gives the developing female information about what resources she can expect from adults. In the absence of such a figure, selection would have favored earlier puberty (and the attendant sexual behavior) such that these resources could be more likely obtained by a sexual partner in the absence of the male parent.
In this brutally honest film, you will be hard-pressed to find a stable father figure (but, an abundance of ineffectual mother figures). This is an almost hermetically sealed female world. Here and there, you can hear pleas for an adult male to make his presence known and to devote some attention to these people. But, the biological father is cluelessly attached to his work and the mother's boyfriend is irreversibly damaged by addiction. Everywhere you look, all you see is damaged women....and the children that are left behind to look for some certainty....somewhere.
From 1976 until 1980, I worked with "emotionally disturbed" adolescent girls about this age. The screaming, the crying, the smashed self-worth.....the cutting. Evolutionary psychology has, at long last, given me some ability to understand that which I once lost sleep over.
Thirteen - Trailer