Volume 6, Spring 2008 - Saddleback College

Fall 2007 Biology 3A Abstracts
both variables (r 2 = 1.3 x 10 -1 ) rejects the null
hypothesis (Fig 2). Results supported our
hypothesis that there would be a positive
correlation between appearance and scent ratings
of males when rated by females.
Average
Rating
Appearance
Average
Rating
Scent
Person
1 3.86 3.33
Person
2 2.46 3.33
Person
3 2.73 2.8
Person
4 3.33 2.6
Person
5 2.53 2.73
Person
6 3.06 2.53
Person
7 2.13 2
Person
8 2.33 2.8
Person
9 3.46 3.26
Mean 2.87 2.82
Table 1. Displaying mean values for each
individual’s appearance and scent ratings. Values
calculated based on ratings by 15 females. Mean
values are shown at the bottom of each column,
with an overall mean difference of 0.05 between
the two variables..
Mean Ratings
3
2.5
2
1.5
1
0.5
0
1
Appearance and Scent Values
Appearan
Scent
Figure 1. Positive correlation of mean ratings
between appearance (Filled bar) and scent
(Slashed bar) of male individuals. (N 1 =9) based on
ratings from females (N 2 =15). An r value of 3.6 x
10 -1 shows positive correlation between the two
variables.
Average Rating
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
0
0 2 4 6 8 10
Individuals
Figure 2. Mean ratings of scent and facial
appearance in each individual on a scatter plot.
Trend line shows linear correlation (r 2 = 1.3 x 10 -
1 ) between both variables.
Discussion
The findings of this experiment support
the hypothesis that a correlation exists between the
attractiveness of a man’s facial features and the
attractiveness of his body odor. There is a
statistically significant relationship between these
two factors in determining a male’s level of
attractiveness to potential mates. This is shown by
the correlation coefficient value of (r = 3.6 x 10 -1 ).
Positive correlation is considered as any r-value
such that 0 < r < 1. An r-value of 1 would indicate
100% positive correlation between each of the
variables being compared.
Mate preference in H. sapiens has
evolved in part because it produces MHC
heterozygous offspring with enhanced levels of
immune competency, which guards against a
greater range of pathogens. Because MHC alleles
are co dominant, the greater the difference
between the alleles carried by the parent’s the
greater the scope of antigen recognition by their
offspring’s immune system (Brown, 1997).
Passing on beneficial genes to offspring largely
influences a females mate choice and her judgment
of male attractiveness. Genetic dissimilarity is
conveyed through both a man’s body odor and his
facial features. Potential mates pickup these visual
and pheromone cues, perceiving genetic
dissimilarity as attractive. The attractiveness of a
man’s facial features and the attractiveness of his
body odor carry overlapping information; women
prefer the smell of facially attractive men
(Rikowski & Grammer 1999). There is a direct
correlation between the attractiveness of a man’s
odor and his facial attractiveness as perceived by
females.
d
Average Rating
Looks
Average Rating
Smell
100
Saddleback Journal of Biology
Spring 2008