Masculine Biology 53

human evolution, the length of this developmental period has grown extensively
because of the increased complexity of human social systems as they relate to
reproduction. Thus, according to Geary, “one important function of childhood is
to provide the experiences needed to refine those competencies that are associ-
ated with intrasexual competition and other reproductive activities in adulthood”
(p. 256). The different pattern of male physical development, play interests,
exploratory behavior and styles, social behaviors such as coalition-formation
for dominance, aggression, and motives “can be readily understood in terms of
sexual selection in general and intrasexual competition in particular” (Geary,
p. 256). For Geary, male sex differences and behaviors “have almost certainly
been shaped by sexual selection, and the majority of these differences have
resulted from male-male competition over access to mates” (p. 257).
Behaviors, such as risk-taking in order to achieve social status and social domi-
nance in groups are more evident in boys than girls (Geary, 1998, pp. 245–246).
Because of the different sexual reproductive strategies adopted by males and
females, a distinctive “pattern of cognitive competencies in the structure and
functioning of many of the brain systems” (Geary, p. 301) evolved in males
and females. Generally, the result is that females demonstrate greater “cog-
nitive competencies associated with one-on-one social relationships,” (Geary,
p. 301) including a greater facility in the use of verbal and written language
than males, while males generally exhibit “cognitive competencies associated
with representing and acting on the large-scale physical environment” (Geary,
p. 302). Those cognitive competencies include solving three-dimensional
geometry problems (Geary). Geary noted that there is more variability in
cognitive performance among males than among females and attributes this
variability to the fragility of boys as a learning group. According to him,

In difficult contexts (e.g. poor health care, inadequate nutri-

tion, and so forth), the prediction is that more boys will be
adversely affected than girls, which, in turn, will result in
an overrepresentation of boys among the lowest scoring
individuals and an underrepresentation of boys among the
highest scoring individuals. (Geary, p. 316; Halpern, 1997)

Consequently, boys are more susceptible to stress related factors and

environmental conditions in modern society than females are (Geary, 1998).
54 CROSSING INTO MANHOOD: A MEN’S STUDIES CURRICULUM

In the past decade, there has been dramatic growth in the development
of the biological sciences as they relate to providing a foundation for
understanding much gender-based behavior, causing some observers to
label this “a revolutionary age in biology” (Fukuyama, 1997). These develop-
ments have had enormous influences on the social sciences, too. Evolutionary
psychologist, David Buss (2004), in an interview with The Evolutionist, an
Internet-based magazine made the following comment:

Five years ago, none of these texts had anything about

evolution. There’s been a massive change; an acceptance
of at least certain aspects of evolutionary psychology that
have never been accepted before. Psychologists in gen-
eral tend to be very empirically minded and so they want
to see the data, and at least the more reasonable ones are
persuaded by data. There are still people that, despite the
evidence, will claim that the sexes are identical... . That
position is getting harder because these results have now
been replicated by independent investigators. But I’ve been
pleased with the overall speed with which these things
have been accepted. I thought it would take a lot longer.
(www.1se.ac.uk/Depts/cpnss/darwin/evo/buss.htm)

In his book, The Evolution of Desire: Strategies of Human Mating

(2003), Buss used a 37-country cross-cultural study to prove that men
and women have markedly different mate-selection strategies: males seek
young, attractive women who will be sexually faithful, but females prefer
males who have material and financial resources, power and high social
status. This difference in mate-selection strategy, according to Buss, is the
result of innate psychological mechanisms that have become hardwired
in the human species as the species has adapted to its environment over
the course of human evolution. Furthermore, Buss (2000) contended that
jealousy is an adaptive emotional behavior that facilitates the human spe-
cies in coping with reproductive threats. Research by molecular biologists
and neuroanatomists, focusing on the chemical and neuronal wiring in the
brain, has localized in the brain such psychological phenomena as lust or
fear, in addition to the ability to appreciate music or the facility to make
choices (Fukuyama, 1997). Neuroanatomist, Laura Allen wrote the following
 Masculine Biology 55

about her research on the human brain: “As I began to look at the human
brain, I kept finding differences. Seven or eight of the ten structures we
measured turned out to be different between men and women” (Sommers,
p. 89). In the future, as the human genome is decoded and understood, more
biological determinants for human behavior are likely to be elicited.

CURRENT NEUROBIOLOGICAL RESEARCH

Perhaps the best known advocate for neurobiological differences in males and
females is Michael Gurian (The Wonder of Boys: What Parents, Mentors
and Educators Can Do to Shape Boys into Exceptional Men, 1996; Boys
and Girls Learn Differently: A Guide for Teachers and Parents, 2001;
What Could He Be Thinking?: How a Man’s Mind Really Works, 2003). In his
research, Gurian asserted that although there are some socialized differences
between the sexes, “there is a primal nature to ‘man’ and ‘woman’ on which
culture has only a minor effect” (2003, p. xxii). While all human brains possess
three similar parts called the brain stem, the limbic system, and the neocortex,
the difference between the male and female brain lies in the size of particular
parts of the brain and how these parts are connected and function together
(Gurian, 2003).
Gurian & Blum (1998) cite current neurobiological research for their
assertions, two of which will be highlighted in this work. The first is the
work of Drs. Ruben and Raquel Gur of the University of Pennsylvania
School of Medicine, who use modern technologies of Positron Emission
Technology (PET) scanning and Magnetic Resonance Imaging (MRI) to
measure how and to what extent males and females use their brains for cer-
tain tasks. One of the findings they discovered is that females use more parts
of their brain than males (Blum, p. 53; Gur, et al. 1995). In another study, the
Gurs did MRI scans on 116 healthy men and women and found evidence
that women have relatively larger brain sections that control aggression
and monitor behavior, while men have relatively larger sections of the brain
that promote aggression. According to Dr. Ruben Gur, “This study provides
neurobiological evidence that women have more brain tissue that’s used cen-
soring aggressive and angry responses, while men have more brain tissue of
the type that initiates aggression and impulsive, angry responses” (VanScoy,
2004, www.hon.ch/News/HSN/509404.html).
56 CROSSING INTO MANHOOD: A MEN’S STUDIES CURRICULUM

Another husband and wife research team, Sally E. and Bennett A. Shaywitz
of the Yale University School of Medicine also used MRI imaging while
giving 19 males and 19 females a rhyming task to complete. According to
their findings published in Nature (1995)

We find significant sex differences in activation patterns

during phonological tasks: in males, brain activation is
localized to left inferior gyrus (IFG) regions; in females
the pattern of activation is very different, engaging more
diffuse neural systems involving both left and right IFG
regions. These data provide the first clear evidence of sex
differences in the functional organization of the brain for
language and indicate that these differences exist at the
level of phonological processing. (pp. 607–609)

This research confirmed the findings of the Gur research team, indicat-
ing that females use both sides of their brain hemispheres more readily than
males. Scientific evidence continues to amass that points to male and female
brain differences that influence behavior and cognition (Halpern, 1997). For
a more complete list of cognitive sex differences, see Appendix B.

MALE BRAIN STRUCTURE

A considerable amount of scientific research has been conducted comparing
male and female brain structures. Pulitzer prize-winning science journalist,
Deborah Blum, in her book Sex on the Brain: The Biological Differences
between Men and Women (1998), discussed the differences between male
and female brain structures. From a size perspective, male brains are generally
15 percent larger than female brains, which have an impact on intelligence,
with males being more adept at spatial reasoning (Blum, pp. 38–39). Another
size differential noted by Blum is that the anterior commissure, a narrow
strip of nerve fibers that connect the two hemispheres together, tends to
be slightly larger in women than in men. Hence, the designation that men’s
brain functioning is more “lateralized,” that is, more brain activity tends to
take place in one hemisphere than the other while undertaking a task (Blum,
p. 46). A third difference between the male and female brain is that the
male brain tends to shrink faster with age with the most visible difference
 Masculine Biology 57

occurring in the frontal lobe (Blum, p. 51). According to Dr. Reuben Gur,
“Men lose tissue in the frontal lobe at such a rate that by the time they reach
middle age, even though they start with larger brains, their frontal lobe is
the same size as the frontal lobe of women” (Blum, p. 52).
Michael Gurian (1996; 1999a; 2001; 2004) cites a number of brain
structure differences between the male and female brain. In males the
corpus callosum, the nerve structure that connects the right hemisphere
of the brain with the left and that facilitates communication between
the two hemispheres, is approximately 25% smaller in males than in
females (Gurian, 1999a, p. 39; 2003, pp. 11–12). The result is that males
have a more difficult time connecting feelings and thoughts to words,
thereby causing males to “have a more difficult time making language out
of experience than women do” (Gurian, 2003, p. 12). A second brain struc-
tural difference is that the frontal lobes, which are responsible for “many
social and cognitive functions related to emotional relationships,” (Gurian,
1999a, p. 39) are smaller in males and develop at a slower rate in male
than in female brains. Because the corpus callosum and frontal lobe brain
structures are smaller, males are more attuned to and adept at spatial activi-
ties, such as hunting and tracking “objects moving through space” as well
as a proclivity for other complex skills involving spatial abilities such as
“mechanical design, measurement, direction, abstraction, and manipulation
of physical objects” (Gurian, 1999a, pp. 38–39; 2003, p. 11; Halpern, 1997,
p. 1094) than women. A third structural difference is in the amygdala, a
brain structure deep within the limbic system that regulates emotional reac-
tions and aggressive responses. This structure is larger in males, thereby
helping males be aggressive. Furthermore, there are fewer synaptic link-
ages from the amygdala to other brain structures such as the frontal lobe
that controls emotions, resulting in “less impulse control and moral deci-
sion making” (Gurian, 2003, p. 14). Another structural difference is the
memory center, known as the hippocampus, which is larger in the female
brain than in the male brain (Gurian, 2003). Additionally, the female brain
possesses more synaptic linkages between the hippocampus and the other
emotive centers than the male brain does, resulting in females having bet-
ter memory capacities for physical and emotional details than males (Gurian,
2003, pp. 14–15). Finally, the cingulate gyrus, a feeling and emotion structure
58 CROSSING INTO MANHOOD: A MEN’S STUDIES CURRICULUM

within the limbic system, is used more extensively by the female brain at rest,
while the male brain at rest has greater synaptic transmissions to the fight-or-
flight brain stem (Gurian, 2003, p. 15). Consequently, women think things
out before engaging in action, whereas males tend to react impulsively when
the fight-or-flight mechanism is triggered (Gurian, 2003, p. 16).
Chemical composition is different between the male and female brains. The
hypothalamus secrets two brain chemicals: serotonin, which regulates mood
and emotion among other things, and oxytocin, which influences the capacity
to bond and maintain healthy interpersonal relations. Studies have shown that
males have less of these two brain chemicals than females; consequently, males
tend to act more impulsively and engage in less bonding (Gurian, 2003, p. 12;
George, 1997, p. 302). For a more complete list and explanation of Gurian’s
gender brain differences with their effects, see Appendix A.

THE ROLE OF TESTOSTERONE

The hypothalamus also secrets testosterone, a powerful hormone that
influences male aggression and sexual behavior. In addition to causing
increased aggression conditioned on the need for asserting or maintaining
dominance or control (Geary, 1998; Clare, 2000), testosterone influences
the size and formation of many brain structures, including the corpus callosum
(Gurian, 2003, p. 8) as well as an influence on “sex-typical patterns of cog-
nitive performance” (Halpern, p. 1095), such as significantly improving
visual-spatial skills. The biological difference between males and females
is caused in large part by the large infusions of testosterone secreted by
the hypothalamus prenatally, at puberty, and throughout life. In males, tes-
tosterone has a virilizing effect that includes the development of the penis
and the scrotum, the deepening of the male vocal chords, and the growth
of facial and body hair. It also promotes the development of male muscle
mass and strength, greater bone density, and overall height. According to
Clare (2000)

The normal woman produces about 200 micrograms of

testosterone and 120 micrograms of estrogen each day, a testos-
terone / estrogen ratio of about 1.6 to 1. The normal male produces
about the same amount of estrogen daily (100 micrograms) but
 Masculine Biology 59

a comparatively huge amount of testosterone—5100 micrograms

per day—giving a testosterone/estrogen ratio of 51 to 1. Not
only do men have very much higher levels of testosterone than
women, they have them at their highest just after puberty and
in the early and mid-twenties—when male antisocial activity
and aggression is at its peak. (p. 20)

Gurian emphasized that adolescent males experience testosterone surges

five to seven times a day, making the hormone a prime mover in the male’s
biology and brain structures (Gurian, 1999a, p. 93).
Coupled with the unique male brain structures and the influence of
testosterone, the following three principal behavior patterns exhibited by
males were identified by Gurian:

1. the search for instant or quick gratification, whether in eating

quickly, jumping from activity to activity, or quick sexual conquest;
2. the tendency to move quickly to problem-solving, even in emotionally
complex experiences;
3. the tendency to find activities through which his body will build physi-
cal tension—like sports or other concentrated, single-task experiences—
then release the tension with an “Ahhh.” (Gurian, 1996, p. 11)

Additionally, Gurian identified other testosterone-driven effects. These

include the male proclivity toward dominance patterns, less inclination to
consider and evaluate the consequences of physical and social aggression
toward others, a delayed reaction and response to emotions, a tendency
toward exhibiting mechanistic, most efficient, behaviors, and uniquely
male structures such as sports and games to prompt emotional develop-
ment and expression (Gurian, 1996, pp. 33–36).

IMPLICATIONS FOR THINKING, FEELING, AND ACTING

Based on the foregoing discussion, several implications can be drawn regarding
the construction of a gender studies curriculum for late adolescent boys.
The growing scientific data documenting the sex differences between
males and females as they relate to behavior, learning, and cognition
make it clear that there is a need to address positively the distinctive
60 CROSSING INTO MANHOOD: A MEN’S STUDIES CURRICULUM

needs of boys. Like girls, boys have a unique and distinctive learning style
that is predicated on their male-specific brain structures and on their chem-
ical, hormonal, and social needs. Educators who work with males need to
understand and appreciate boys’ distinctive ways of acting, thinking, and
behaving. Additionally, Michael Gurian stated that there is a need for more
gender education to help students learn about themselves and how they
tick (2001).
This conclusion flies in the face of the current gender-equity movement
which disapproves and seeks to eliminate typical, healthy male behaviors,
such as rough-and-tumble play and natural boy-type aggressiveness, and
replace it with feminine activities and a feminized educational curriculum
(Sommers, 2000). According to Sommers, those educators who embrace
the ideology of the gender equity movement state that these healthy
male behaviors “are not natural but are artifacts of culture,” and they
“embrace the belief that gender-fair schools will require a new peda-
gogy that upsets and neutralizes many behavioral conventions associ-
ated with being a boy or a girl” (Sommers, p. 85). Anthony Pellegrini,
an early-childhood education professor at the University of Minnesota,
saw the elimination of rough-and-tumble play and recess as profound
insensitivity to boys’ biologically driven natural play needs (Pellegrini
et al., 1995). A revisioning and a rethinking of the manner in which the
educational and social needs of boys are addressed in the school setting
is needed.
The first implication for a gender studies curriculum is the need to address
boys’ unique male biological, hormonal, and brain structures. Such a cur-
riculum can take the brain structures and hormones listed in Appendix B
as a starting point to address with boys their distinctive biological heritage
and make up. By educating boys about their distinctive male biology and
making them aware of how their own internal processes work, teachers
can assist boys in becoming more self-regulating of their hormones and
biologically-driven behaviors.
Advocating a male-friendly focus on the biological uniqueness and differ-
ences between males and females, however, does not mean that one sex is
smarter or better than the other. Such valuations have no place in a mascu-
line gender studies curriculum. Halpern (1997) researched this issue and
 Masculine Biology 61

concluded with the following:

Some of the differences favor females and some favor males.
It is about as meaningful to ask “Which is the smarter sex?”
or “Which has the better brain?” as it is to ask “Which has the
better genitals?” Bigotry does not stem from the fact that
there are group differences; it arises in the evaluation of the
differences, when group members decide that the traits and
abilities associated with other groups are inferior to the ones
found in their own group. (Halpern, 1997)
The use of biological differences in an attempt to advance a political
agenda or to be politically correct is an abuse of the information itself and
an abuse on the gender on which the data are used (Halpern, p. 1098).
A second implication for a gender studies curriculum is the context in
which such a curriculum is to be taught. Halpern (1997) suggested that
there may be social reasons for considering single-sex education classes.
Sommers (2000) cited a 1998 report by British headmasters entitled “Can Boys
Do Better?” that advocates for one-sex classrooms among other gender-specific
strategies. Stephen Webb (Webb, 2001) called for a reconsideration of all-male
education as one viable alternative to educating boys. Because adolescence
is such “an emotionally-charged period of transition and transformation ...
(f)or some people, this passage is best navigated apart (somewhat) from
the other sex” (Webb, pp. 601+). A masculine gender studies curriculum
seems the perfect setting for an all-male grouping of late adolescent boys.
Webb expressed the rationale for single-sex classrooms by saying, “separa-
tion also creates and encourages a special bonding between members of
the same sex. This is especially important today, when males are often not
encouraged to articulate and express the full range of their human emotions
and needs” (Webb, pp. 601+). Therefore, all male classrooms permit an
honesty that might not otherwise be forthcoming in a mixed sex classroom
setting. The Haverford School in Philadelphia, Pennsylvania, a private, all-
male school, understands and values the unique needs of boys. In 1994, the
school created a resource center for discussing and thinking about boys’
lives. Called The Men’s Studies Project, it employs careful research and
scholarship to help parents, educators, and communities effectively raise,
educate, understand, and support boys. Dr. Michael Reichert, the project’s