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Facial symmetry
A person’s face is key to how
attractive others find them.
Humans and monkeys prefer
symmetrical faces—symmetry
is an indicator of good health
and genetics. Many species also
favor sexually dimorphic faces,
males preferring feminine faces
and vice versa. These factors
interact: higher facial symmetry
increases a face’s perceived
femininity or masculinity.European
When shown composite faces with high
or low symmetry, European observers
judged high-symmetry faces to appear
more feminine or masculine.Hadza
Similar results were found in the Hadza
people, an indigenous Tanzanian ethnic
group. This suggests that the link between
symmetry and attractiveness is universal.69%
62%
31%
37%
85%
60%
15%
39%
FEMALE MALE
KEY
Symmetrical
faceAsymmetrical
faceOXYTOCIN REDUCES
ACTIVITY IN THE
BRAIN’S FEAR CENTER
Hypothalamus
triggers
production of
sex hormones
by testes or
ovariesIncreased levels
of testosterone
and estrogenIncreased
libidoSEX^ H
ORMONES
Lust
Lust is the primeval urge to engage in
sexual relationships, driven by the sex
hormones testosterone and estrogen.
While they increase libido in men and
women respectively, they alone do
not induce lasting connections.Percentage of
people who
found face
sex-typicalPercentage of
people who
found face
sex-typical
Attachment
The hormones oxytocin and vasopressin
have multiple effects—including making
us feel more protective of our object of
attraction and attentive to their needs.
They stimulate long-term bond formation
but can increase distrust of others.DOPAMINE
NORA
DRENALINE
Brain
produces
oxytocinOxytocin
levels
increased Feelings of
bonding and
contentmentOXYTOCIN
Brain
produces
vasopressinVasopressin
levels
increasedFeelings of
bonding and
attentivenessVASOPRESSIN
US_114-115_Sex_and_love.indd 115 20/09/2019 12:36