Saddleback Journal of Biology - Saddleback College

Spring 2010 Biology 3B Paper
Table 2. Average ratio and selection percentage of male subjects in study 2 for long-term relationships.
Subject
#1
Subject
#2
Subject
#3
Subject
#4
Subject
#5
Average
Symmetry
Ratio
(%)
Selection
Percentage
(Menstruating)
Selection
Percentage
(Nonmenstruating)
98.58 98.97 96.48 98.68 98.07
38 12 12 26 12
36 14 4 25 21
Discussion
Favorable body odor has been shown to be
linked to a higher degree of bilateral facial symmetry,
and a high degree of bilateral facial symmetry is
linked to good genetics. When looking for a mate,
women should take these cues into consideration.
Research has shown that women will have peaks in
there degree of sexual desire, during these peaks
women are believe to place greater selection
pressures on those they would choose for a mate
(P.C. Regan 1996). This study looked at if these
peaks in sexual desire would affect the women’s
choice in male subjects based on olfaction, causing
the women to choose individuals with higher degrees
of bilateral facial symmetry. However in our study it
has been shown that the peak in sexual desire during
the week of menstruation does not have an effect on
the females’ choice of male mates for a long-term
relationship.
In the first study there were two individuals
who were chosen significantly more by the
menstruating group (subject #4 and #5). These two
individuals did not have a high degree of bilateral
facial symmetry and were very rarely chosen
compared to the amount of the times other male
subjects were chosen. Therefore with a larger sample
size of women this apparent anomaly may disappear.
This anomaly also appeared in the second study with
one individual (subject #3). This is believed to be an
anomaly since it is only seen in the individuals that
were selected a total of three times or less.
The second study there was one individual
who was chosen significantly more often for a shortterm
relationship. This individual did not have the
highest degree of bilateral facial symmetry but he
was within one percent difference from the male with
the greatest degree of symmetry. This finding was
unexpected since it is believed that women will put
greater selection pressures on mates during the week
of menstruation and that they would choose the
individual with the greatest degree of facial
symmetry. To elaborate on this study it would be
beneficial to do an extended study where female
subjects are followed for many months to see if they
would select the individual with greater symmetry
more often when they are menstruating and on there
peak time of sexual desire.
This study supports the findings from
previous research; women prefer the body odor of
male subjects that have a high degree of bilateral
facial symmetry. However it appears that the
menstrual cycle does not affect a women’s selection
of male mates based on their body odor. The peaks in
hormones that have been studied may not have a
strong effect on the women’s olfaction and therefore
they are not more susceptible to olfactory cues for
good genetics.
In this study it was noted that when males
are within 1% difference in the degree of facial
symmetry there was no significant difference in their
selection count for a long-term relationship or a
short-term relationship. When the degree of
symmetry is this close, the males who have more
masculine features may have a more masculine scent
that is preferred by women (Cornwell, R. E. et al.
2004).
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Saddleback Journal of Biology
Spring 2010