The document discusses several factors related to human sexual attraction and mating behaviors. It describes how symmetry is seen as attractive in faces, and proximity, similarity and reciprocity are important in choosing partners. Relatives have similar scents that are seen as unsexy. Women are choosier than men in choosing mates and look for status and security. Hormones like vasopressin and oxytocin play a role in monogamous behaviors in some species.

1. The Science of Sex Appeal

2. Symmetry
• Research shows that people prefer more symmetrical faces.
• Research shows that there are three major factors:
proximity, similarity and reciprocity. We look for someone
who is physically close, someone who has similar
interests, and someone who will love us back

3. Unsexy Scents
• During their monthly cycle, women’s noses help them
seek out a suitable mate.
• Researchers decided to do an experiment to see how
women reacted to the smell of relatives. They used
tshirts used by different people with the smell of their
sweat on them. Various women would take a survey
and decide if the smell was sexy or unsexy. The
researchers placed one tshirt that smelled of one of
the women’s relatives. The women responded with
unsexy.
• Relatives have a very similar immune system and a very
similar odor to us and that similar odor turns us off.

4. Women are Choosier
• The reason why women are choosier about men is because sex can
be much costlier for them. Men can have sex and walk
away, women can have 9 months of pregnancy and child care.
• Women look for status and wealth in a man. They want security.
• Research shows that a man’s car affects women’s perception of
men and what their personality is like. Women prefer cars that
show dominance and safety.

5. Mating for Life
• Women tend to prefer guys with more masculine faces
when they’re ovulating, and more feminine faces when
they’re not ovulating.
• Some women may be biologically driven to
promiscuity.

6. Shapely Figures
• Recent neuroscience has identified a part of the brain that’s
intensely active when it’s looking at a human body.
• Many factors influence the length of time we look at a body
or the attractiveness of it, like clothes, jewelry, and hair.
• When asked to identify solid figures on a screen as either
male or female, participants looked at the hips and
waist, clear indicators if the figure was male or female.

7. Is Monogamy the Answer?
• What keeps humans from straying from their mate?
• 90% of North American Prairie Voles spend their entire adult lives with one
partner.
• When scientists looked in the brains of monogamous male voles, they found high
levels of a hormone of vasopressin.
• When they scanned the brains of promiscuous male voles, they found decreased
levels of the hormone vasopressin.
• Vasopressin is found in high levels in monogamous men, and oxytocin is found in
high levels in monogamous women.
Oxytocin Vasopressin

8. Voices on Estrogen
• A study shows that women’s voices are more
attractive when they are in the middle of their
cycle, when they are ovulating and most fertile.
• Their voices are slightly higher.