Men are not from mars and
women are not from venus:
we are the same species and from the
same planet get used to it!
Agustín Fuentes
U of Notre Dame
THE BIG MYTH
What do you make of the two
versions of Genesis?
1-27 So God created man in his [own]
image, in the image of God he
created him; male and female he
created them.
2-5 And every plant of the field before it was in the earth,
and every herb of the field before it grew: for the LORD
God had not caused it to rain upon the earth, and [there
was] not a man to till the ground.
…
2-7 And the LORD God formed man [of] the dust of the
ground, and breathed into his nostrils the breath of life; and
man became a living soul
18 And the LORD God said, [It is] not good that the man
should be alone; I will make him an help meet for him.
19 And out of the ground the LORD God formed every
beast of the field, and every fowl of the air; and brought
[them] unto Adam to see what he would call them: and
whatsoever Adam called every living creature, that [was]
the name thereof.
20 And Adam gave names to all cattle, and to the fowl of
the air, and to every beast of the field; but for Adam there
was not found an help meet for him.
21 And the LORD God caused a deep sleep to fall upon
Adam, and he slept: and he took one of his ribs, and closed
up the flesh instead thereof;
22 And the rib, which the LORD God had taken from man,
made he a woman, and brought her unto the man
“Men are equipped to impregnate women. There is no cost to a man in
impregnating someone. Women, on the other hand, are equipped to be
impregnated and produce babies. As soon as a woman gets pregnant she has
just signed on for a 20 year tour of duty taking care of the resulting child. Her
goal, going back millions of years, is to help that baby survive. For a woman
pregnancy carries an extremely high cost. Furthermore, the woman’s mind
and body also know, instinctively at some level, that a baby needs two people
to survive. Women are therefore designed to wait for a strong commitment
prior to getting pregnant. In our culture that commitment is called
"marriage," and women are smart to wait for it. Many men seem to have
little or no such programming. This basic anatomical difference, by itself,
leads to rather strong differences in priorities between men and women. In
addition, men and women clearly have different programming in other parts
of their brains. For example, men are much more aggressive, in general, than
women, while women tend to be much more nurturing. Men are more
individualistic, while women are more social. Men tend to rely more on
rational thought, while women rely more on feelings. These observations are
generalizations, of course, but they are fairly obvious. You can see these
tendencies in children at play. Girls play with dolls and work with each other
socially, while boys wage mock wars with one another. Neither mode is
"better" than the other. They are simply different, and they have their own
places”
•
Marshall Brain (1997) The Teenagers guide to the Real World BYG Publishing.
sexuality?
• “When it comes to the matter of desire, evolution
leaves little to chance. Human sexual behavior is not a
free-form performance, biologists are finding, but is
guided at every turn by genetic programs.” –Nicholas Wade
(journalist) in the New York Times April 10, 2007
BUT
• “Although sex is a biological urge, it is rarely
experienced in the same ways by people everywhere: it
is differently practiced and felt depending on the social
and cultural settings in which it occurs” Hastings Donnana and Fiona
Magowan (Anthropologists) F. (2010) The Anthropology of Sex Berg Publishers
But…data?
• “The gender similarities hypothesis holds that males and females
are similar on most, but not all, psychological variables. That is, men
and women, as well as boys and girls, are more alike than they are
different….Results from a review of 46 meta-analyses support the
gender similarities hypothesis. Gender differences can vary
substantially in magnitude at different ages and depend on the
context in which measurement occurs…. The question of the
magnitude of psychological gender differences is more than just an
academic concern. There are serious costs of overinflated claims of
gender differences. These costs occur in many areas, including
work, parenting, and relationships.”
– Janet Shibley Hyde (2005) The Gender Similarities Hypothesis
American Psychologist Vol. 60, No. 6, 581–592
male and female biology: we’re made
of the same stuff
•
•
•
•
Hormones! Variation on a theme
Genitals! Variation on a theme
Bones/body! Variation on a theme
Growth and development patterns! Variation
on a theme
• Biology and Perception:
variation versus differentiation
Brain?
Brain? Data…
• “…what I found after an exhaustive search, was
surprisingly little solid evidence of sex differences
in children’s brains. Sure, there are studies that
do find differences, but when I looked closely at
all the data—not just the research that confirms
what we already know about boys’ and girls’
behavior but a truly balanced collection of
findings—I had to admit that only two facts have
been reliably proven: boys’ brains are larger than
girls and girls’ brains finish growing earlier than
boys’.” - Lise Eliot (Neuroscientist)(2009) Pink brain Blue brain. Houhgton
Mifflin Harcourt
SG
Brain diifs?
• straight gyrus (SG) and “femininity”
(part of ventral frontal cortex (VFC)
“The origins of the relationship between sexual
dimorphism of SG morphology and social cognition
have not yet been elucidated.” Wood, J.L. Murko,V., and
Nopoulos, P. (2008) Ventral frontal cortex in children: morphology, social
cognition and femininity/masculinity. SCAN (2008) 3,168–176
• CC
• “A meta-analysis of 49 studies published since 1980
reveals no significant sex difference in the size or
shape of the splenium of the corpus callosum,
whether or not an appropriate adjustment is made
for brain size using analysis of covariance or linear
regression…. The wide spread belief that women
have a larger splenium than men and consequently
think differently is untenable.” Bishop, K. and Wahlsten, D.
(1997) Sex Differences in the Human Corpus Callosum: Myth or Reality?
Neuroscience and Biobehavioral Reviews 21(5):581-601
• Biology: we are all Homo sapiens AND we are a sexually
reproducing species --sexes are like as much, if not more, than
they differ.
• Modern gender context: substantial differences between men
and women, but very few of those elements match the actual
biological patterns in our species.
• There are important Real patterns:
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Males are often larger with denser muscles than females
aspects of our skeletons are variations on a theme but have an impact
Fat distribution and use
Reproductive aspects: gestation and lactation
• males and females are no the same…BUT biological
differences between the sexes are much smaller than the
behavioral differences between the genders.
Behavior and potential?
• “It does appear that on many, many different
human attributes-height, weight, propensity
for criminality, overall IQ, mathematical
ability, scientific ability-there is relatively clear
evidence that whatever the difference in
means-which can be debated-there is a
difference in the standard deviation, and
variability of a male and a female population.”
-Lawrence Summers (former president of Harvard University) remarks at NBER Conference
on Diversifying the Science & Engineering Workforce January 14 2005
Behavior and potentialthe misrepresented dataset
• Maccoby and Jacklin 1974 meta-analysis
– 2,000 reports of gender differences
– Vast majority of societal assumptions about
differences were not supported
– Found core differences in four specific areas: verbal
ability, visual-spatial ability, mathematical ability, and
aggression.
…we tend to forget that Maccoby and Jacklin’s main
point was of gender similarities.
•
Maccoby, E. E., & Jacklin, C. N. (1974). The psychology of sex differences. Stanford, CA: Stanford
University Press
Shibley Hyde’s data
Janet Shibley Hyde (2005) The Gender Similarities Hypothesis American Psychologist Vol. 60, No. 6, 581–592
• 46 previous meta-analyses of male-female differences (published between
1980-2004) consisting of nearly 5000 reports and assessing 128
psychological measures.
• gender similarities hypothesis supported if “most psychological gender
differences are in the close-to zero (d ≤0.10) or small (0.11 < d <0.35)
range, a few are in the moderate range (0.36 <d <0.65), and very few are
large (d <0.66 <1.00) or very large (d >1.00).”
• Results: 78% of the d measures are small or close to zero (38% d ≤0.10,
and 40% 0.11 < d <0.35). Most between male and female differences are
extremely slight.
• Where are the large gender differences? Males scored noticeably higher
(d>0.35) in grip strength, sprinting, throwing velocity and throwing
distance, masturbation, views on casual sex, physical aggression, and
mental rotation of objects. Females scored noticeably higher on indirect
aggression, agreeableness, and smiling.
one can easily see that the vast majority of the
assumed male-female differences in the
psychological and skill variables overlap,
extensively. This is even more impressive when
you consider that this graph is the overall
mean of the entire dataset and that 78% of the
actual measures have even less difference and
more overlap than shown in the graph!
Aggression: aha, differences!
• Males generally display more physical aggression than
females
• Males display slightly more verbal aggression than
females
• There is no difference in the rates of anger displayed by
males and females
• As young girls females display more indirect aggression
than males, but this drops to equal levels by
adulthood.
•
Meta-analyses by John Archer: Archer, J. (2009) Does sexual selection explain human sex
differences in aggression? Behavioral and Brain Sciences 32:249-311 and Archer, J. (2004) Sex
differences in aggression in real world settings: a meta-analytic review. Review of general
Psychology 8:291-322
However….not so clear
•
greater variability in males’ display of physical aggression than in females’ physical aggression: but this is
not true for other types of aggression
•
gender differences start around 2 years of age. Rates of physical aggression peak (2-3 years of age) and
then decline until about 9-11 years of age in both males and females. At 2 years of age and even after
the decline, overall rates of physical aggression are generally higher in males.
•
On average, males do seem to show more physical aggression than females in same-gender conflicts
and in general use of aggression.
•
nearly half of males who displayed high rates aggression in early childhood retained that aggression
pattern into middle adulthood, whereas only 18% of females who displayed high aggression in early
childhood maintained it into middle adulthood. BUT both males and females who displayed low
aggression during early childhood had the same pattern of retention into middle adulthood (38% and
36% respectively).
– differential socialization for males and females is especially interesting given that there does not
seem to be a link between physical aggression and the testosterone spike in males at puberty,
which might have been an explanation for the maintenance of increased high aggression into
adulthood by males.
•
Huesmann, L.R, Dubow, E.F., and Boxer, P. (2011) The transmission of aggressiveness across generations: biological, contextual, and social learning processes. In
Shaver, P.R. and Mikulincer, M. Eds. Human Aggression and Violence: causes, manifestations, and consequences. American Psychological Association Pp.123-142 and
Archer, J. (2009) Does sexual selection explain human sex differences in aggression? Behavioral and Brain Sciences 32:249-311
aggression differences between males and females
in heterosexual partner relationships…hmm.
•
•
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Little differences between genders in rates of physical aggression in heterosexual couples
Except: overall use of physical aggression slightly higher in females than males.: women were
significantly more likely to commit most acts of physical aggression, except for using weapons and
actually beating up partners
However, males were higher in extreme violence (serious psychical aggression resulting in injury)
and women were more likely to receive serious injuries .
•
“this relative equality between the sexes in acts of physical aggression was confined to nations
where women have higher levels of societal power…. The magnitude and direction of the sex
difference followed a measure of societal gender empowerment and beliefs about gender roles.”
–John Archer
•
meta-analyses of cross cultural partner physical aggression demonstrates a direct tie to the
Gender empowerment index: the lower the female empowerment rating the higher the male bias
in partner based physical aggression.
•
worth noting that overviews of crime statistics from North America and Europe indicate that
males are more likely to be involved in violent crimes and same-gender homicides. Nearly 80% of
those involved in weapon based crimes are male and about 97% of same-gender homicides
involve males.
Gender?
•
The Psychologists Wendy Wood and Alice H. Eagly argue for a biosocial approach
to gender that attempts to fuse biological and cultural developments together to
better understand certain patterns in gendered difference.
•
anthropological records of hundreds of societies: gender roles, division of labor
and patterns of sex/gender differences over time.
•
gender emerges from the combination of our bodies, cultures and individual
experiences. Our bodies are shaped by our evolutionary histories, resulting in
some important differences, but so are our brains resulting in important
similarities in behavior and potential.
•
Wood and Eagly found that there is variation in the roles males and females play
across societies, with high degrees of overlap in many areas, but greater
differences being found in aspects of those societies that deal directly with size
and strength or giving birth and taking care of young children, and that other
patterns become associated or emerge from, these differences.
•
Wood, W. and Eagly, A.H (2002) A Cross-Cultural Analysis of the Behavior of Women and Men: Implications for the Origins of Sex
Differences. Psychological Bulletin 128(5):699–727.
The fact that aspects of our societies are biased towards male control is not part of our
evolutionary heritage, it is part of our cultural reality.
• “The Global Gender Gap Report 2010 : over 96% of the gap on health
outcomes, 93% of the gap on educational attainment, 59% of the gap on
economic participation and 18% of the gap on political empowerment
have been closed. No country in the world has achieved gender equality.”
• There is a gender gap in economic and political power that constructs and
helps maintain gender roles and inequality.
• USA?
– 19th place (up from 31st out of 134 in 2009), with an overall gap index
of 74%
– overall score reflects the percentage attainment by females relative to
males in the areas of interest.
• parity in educational attainment (we are tied for #1) and
participation in the workforce (we are tied for 6th place).
– But…income and wage inequality we are 64th
– political empowerment – we are 40th
•
The Global Gender Gap Report 2010 Hausmann,R., Tyson, L.D., and Zahidi, S. (2010) World Economic Forum
• Men make more money for similar work, hold more
positions of power and predominate in political roles.
This is a global pattern, but not an evolutionary one.
There are no patterns of biological or behavioral
differences between males and females that make
males run companies or societies better. These are
aspects of societal structures that act to maintain
broadly held ideas about gender. When children grow
up within them, they acquire the templates that are
around them. These contexts set the stage for our
biosocial development to produce what we experience
on a day to day basis.
Sexual behavior?
2010 National Survey of Sexual Health and Behavior, a nationally representative study of 5,865adolesecnts and adults
Center for Sexual Health Promotion at the University of Indiana- Journal of Sexual Medicine volume 7, supplement 5.
•
Masturbation: Patterns statistically similar, males slightly higher and females in 20-29 age group reported the highest
rates of solo masturbation.
•
Vaginal intercourse: This measure varied substantially across the lifetime but females and males almost identical in
frequency except with later ages
•
Partnered non-coital behavior: Again almost no differences in frequencies
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Anal intercourse: in men and women the numbers are almost identical except that females report slightly higher
frequencies of anal sex over a larger age range (18-69) than males.
•
Two interesting differences :
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Same-sex sexual behavior:. Across all age categories about 8-10% of men reported engaging in same-sex sexual
activity during their lifetime, with higher numbers (13-15%) reported in the 40-59 age groups. About 5-9% of women
report participation in same sex sexual behavior during their lifetime, with much higher figures (up to 17%) for the
20-39 age group. One key difference between males and females is that a higher percentage of males reported samesex encounters in the past month or year than did females (except for females 20-24 and 30-39).
•
decline in sexual activity with age (especially over 60) in both sexes. However, the female decline is bit larger than
the males’. This is a pattern observed in other studies where as females age their overall participation in sex goes
down (on average). This is especially acute in married couples with females’ participation in sexual activity with their
partners negatively correlated with the length of time married.
•
See Lindau, S.T., Schumm, L.P., Laumann, E.O., Levinson, W., O'Muircheartaigh,C.A., and Waite, L.J. (2007) A Study of Sexuality and Health among Older Adults in the United States. New England Journal of
Medicine 357(8):762-774 and Brewis, A. and Meyer, M (2005) Marital coitus across the life course. Journal of Biocultural Science 37:499-518
Socio-sexuality?
• “In the present study, the most consistent finding was that
men scored higher on sociosexuality than women across
cultures. Several different theories were evaluated
concerning why men and women differ in this way. They all
received at least some empirical support. As a result, we
are left with the relatively unsatisfying conclusion that
sociosexual sex differences are predictable from several
theoretical perspectives, none of which is conspicuously
superior to the others…At present, it appears that multiple
perspectives are required to more fully explain the cultural
and gender-linked variance in sociosexuality.” --David P. Schmitt
(Psychologist) (2005) Sociosexuality from Argentina to Zimbabwe: A 48-nation
study of sex, culture, and strategies of human mating Behavioral and Brain
Sciences 28:247–311
Basic conclusions
Not that there are no differences…rather that
we need to carefully construct our questions
and collect data…
common sense and cultural schemata are
“real” but they are not biological facts
We really are the same species…that means
something
categories of interest: what are we
asking and why are we asking it?
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Male-Female patterns
Gender patterns
Masculine-feminine issues
Human patterns
Sex
Age
Health
Sexuality
Economic status
Political power
Athletic ability
• No simple or single explanation…the answer cannot
be “because we are different”
So why do many find this funny?
And what does it say about us?
Tackling myths is difficult but really
important
Being human is pretty complex,
but thanks for listening