Adolescence is too large a segment of the human lifespan to consider as a single unit. Certain characteristics separate early, middle, and late adolescence (Group for the Advancement of Psychiatry, 1968). Early adolescence is a period of some turmoil associated with dramatic physical changes. Rapid mood swings, regression with the reappearance of early childhood behavior and dependency, angry rebellion against parents and other adults, and a tendency to be with members of the same sex, are all in evidence at this time. By late adolescence, a more comfortable distance from parents is typical, with the adolescent accepting their own inner life.
The transition
toward an adult way of life is noticeable, with a shift to opposite-sex relationships, an
interest in intimate and complete erotic experiences with members of the opposite sex,
progress in the selection of career choice, and perhaps even a marriage partner.
According to Ramsey (1943), exceedingly few males modify their attitudes on
matters of erotic experience or change their patterns of overt behavior in any
fundamental way after their middle teens. They may change certain details of activity
in their erotic lives, and some individuals may acquire entirely new attitudes on
matters of sex, but they form the exception rather than the rule.
There is no evidence that it is possible for any male who is not physically
incapacitated to be able to get along without some kind of regular sexual outlet from
the time of adolescence until old age reduces his responsiveness and his capacity to
function sexually (Kinsey, 1948, p. 218-262). Among unmarried males, the frequency
of orgasm is at a maximum somewhere between the ages of sixteen and eighteen.
Among married males, there is no age at which sexual activity is more frequent than
it is among the males in their late teens and early twenties (Kinsey, 1953, p. 14). More
females than males get along without sexual outlet in their teens.
The source of first ejaculation for males, which often occurs between ages
thirteen and fifteen, are: masturbation, nocturnal emissions, heterosexual coitus, and
homosexual encounters; with spontaneous ejaculations, petting to climax, and
intercourse with animals as less frequent stimuli for the initial experience (Kinsey,
1948, p. 190).
Adolescents today are reaching puberty three years sooner-in some
communities five years sooner-than they once did, and this may affect the onset of
various kinds of sexual activity (Tanner, 1968). The trend toward earlier maturation
is perhaps best shown by statistics in the age of menarche, the first menstrual period.
The age of the first appearance of pubic hair is an index, but is a less reliable index
of puberty. Girls have experienced menarche earlier during the last 100 years by
between three and four months per decade.
On this basis, puberty is attained from
two, two and a half, to three years earlier than it was a century ago. Age at menarche
in Norway dropped from 17 plus years of age in the 1840s to about 13.4 years of age
in the 1950s. In Germany, the average age in 1795 was 16.6 years, but by 1920, it
was 14.5 years. In the United States, the age was about 14.2 years in the 1900s,
13.5 in the late 1930s, while data from the mid-1960s indicate a drop to about 13
years. This trend toward earlier menarche may continue for at least another decade
or two.
More than 99 percent of the boys in the Kinsey sample began regular sexual lives
immediately after first ejaculation. In this respect, the male is very different from the
female, for there are many women who go for periods ranging from a year to ten or
twenty years between their earlier sex experiences and the subsequent adoption of
regularity in sexual activity. The male in the course of his life may change the sources
and objects of his sexual outlets, and his frequency may vary through the weeks and
months and over a span of years, but there is almost never a complete cessation of
sexual activity until such time as old age stops all response (Kinsey, 1948, p. 192).