Traditionally, pubertal timing has been viewed as the product of genetic and nutritional factors. Belsky, Steinberg, and Draper (1991), however, have proposed that menarche (the first menstrual cycle) is determined to some degree by social cues that are experienced by individuals during childhood. They contend that pubertal onset and patterns of adult sexual behavior reflect reproductive strategies that are contingent upon the social milieu in which an individual develops. Young girls who are reared by mothers with no single long-term partner tend to enter puberty earlier, become sexually active earlier, and have more sexual partners than girls coming from households having both mother and father. According to Belsky et al. (1991), the ability of these individuals to form lasting and strong pair bonds and their earlier sexual maturation reflect evolutionary strategies designed to cope with environments where resources are inadequate or unreliable and adult pair bonds are not enduring. Thus, growing up in a fatherless home during the first five to seven years of life triggers a kind of quantitative reproductive strategy. A quantitative strategy pays off by producing more offspring to offset the disadvantages posed by a lack of male provisioning for the young.
Ellis, McFadyen-Ketchum,
Dodge, Pettit and Bates (1999) conducted a longitudinal study to test Belsky’s
evolutionary model of menarcheal timing. These researchers observed 173 girls
and their families for eight years to determine if more negative-coercive
family relationships in early childhood provoke earlier reproductive
development in adolescence. It was found that the quality of a fathers'
investment in the family was the most important aspect of the proximal family
environment relative to influencing a daughter’s pubertal timing. Girls reared
in father-absent homes reached menarche several months earlier than their peers
in father-present homes. The longer the paternal absence, the earlier was the onset
of puberty. However, if the father was present but had an abusive relationship
with their daughter then the daughter’s menarche was also earlier. The greater
the time spent by fathers in child care and the greater the level of father-
daughter affection, the more delayed was the onset of menarche.
The proximate mechanism for
delaying the onset of menarche is probably the chronic release of stress
hormones. Extremely high levels of stress delay pubertal onset, but chronically
moderate levels such as those associated with the experience of a fatherless
household produce the opposite effect. Mothers can affect their daughter’s
pubertal timing by creating a stressful home environment. In a short-term
longitudinal study of 87 adolescent girls (aged 11-13 yrs), it was found that a
history of mood disorders in mothers predicted earlier pubertal timing in
daughters (Ellis and Garber, 2000). In families where the mother was involved
with a male who was not the biological father, interpersonal stress accounted
for almost half of the variation in daughters' pubertal timing.
Ellis and Garber (2000) have proposed that in addition to family stress, a second path to early pubertal maturation in girls is the presence of a stepfather. They hypothesize that pheromones emitted by adult men other than the biological father, such as stepfathers or the mother’s boyfriends activate physiological mechanisms that accelerate pubertal onset in young girls. Their research showed that Stepfather presence, rather than biological father absence, best accounted for earlier pubertal maturation in girls living apart from their biological fathers.
In addition to entering
puberty earlier, girls who are reared by mothers with no single long-term
partner become sexually active earlier, and have more sexual partners than
girls coming from households having both mother and father (Belsky et al.,
1991). The inability to form lasting pair bonds in these individuals may in
part be due to the typically impaired orgasmic potential characteristic of many
women reared in father absent households (Thornhill & Gangestad, 1996).
Individuals who grew up in a two-parent
household with a reliably investing and nurturing father during their first
five to seven years of life develop a very different set of social expectations
about the nature of other people. Their pubertal timing is delayed, thus
insuring that they remain in the nest for a longer period of time. And when
they reach sexual maturity their patterns of mating are oriented toward a more
qualitative reproductive strategy. They are involved with a fairly limited
number of sexual partners throughout their lifetime and in young adulthood most
become strongly pair bonded to one other individual. Thus they display a
reproductive strategy oriented toward producing a limited number of offspring
with maximal investment from both parents.