Finger Length and Longevity

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Finger Length and Longevity Kadi
Schantz Sponsored by Dr. Howard M. Reid,
Psychology Department
Abstract The ratio of index finger length to
ring finger length (2D4D) is an indicator of the
level of testosterone exposure in the womb. For
adult males, this ratio has been found to be
related to a number of variables, including
higher physical aggression. In the current study,
we are examining a possible relationship between
finger length and longevity. Specifically, men
are consistently reported to have a shorter
average life span than women. We predict that
those men who live to be elderly will exhibit
more symmetrical finger lengths, and thus will
have digit ratios more characteristic of women.
Introduction The ratio of second to fourth
finger length (2D4D) has been shown to differ
for men and women. Specifically, men tend to
have shorter index than ring fingers while these
fingers have been found to be of more even length
in women. This has been reported to be due to the
inhibitory effect of testosterone on the growth
of the index fingers of the male fetus.
Researchers have related the ratio of index and
ring finger lengths to numerous aspects of life.
For instance, Bailey and Hurd (2005) reported
that men with a more masculine finger length
ratio had higher physical aggression scores than
men with more feminine finger length ratios.
Bailey and Hurd (2005) also found a relationship
in men between a more even finger length ratio,
which is characteristic of women, and higher
rates of depression. This had been predicted,
for women have been reported to exhibit higher
levels of depression than men in numerous studies.
Research Question Since it has also been
noted that women generally live longer than men,
we are examining whether men with more feminine
digit ratios (more even index and ring finger
lengths) have an increased likelihood of reaching
old age than men who have more masculine digit
ratios (shorter index than ring fingers).
Methods Participants One hundred three
students (60 women and 43 men) enrolled in a
variety of courses at Buffalo State College have
taken part in a pilot study. We now plan to
collect data from fifty (25 male and 25 female)
young adults and an additional fifty (25 male and
25 female) elderly subjects. Materials and
Procedure The proposed research involves
measuring the lengths of the second and fourth
fingers of two different age groups, young adults
and the aged. This will be accomplished using
the procedure of Manning, Fink, Neave and Caswell
(2005). Specifically, subjects will place each
of their hands palm down, with the fingers
together, in a photocopy machine. Subsequently,
the lengths of the fingers will be measured from
the photocopies by raters who are blind to the
purpose of the study.
Participants will also be asked to fill out a
questionnaire consisting of questions regarding
health and lifestyle choices such as drinking,
smoking, nutrition, and exercise. The
questionnaire also includes the BEM Sex Role
Inventory. This is a commonly used measure in
psychological studies and evaluations. The BEM
will be used to examine whether there is an
association between masculinity/femininity and
2D4D in the elderly males. Results Old age
homes have been contacted and data will soon
begin to be collected. Discussion The ratio
of index finger length to ring finger length
(2D4D) has been found to be related to a number
of characteristics, particularly for men. As
would be expected, those men with a masculine
digit ratio (relatively shorter index than ring
fingers) have been reported to be more
aggressive. Also, those men with a more feminine
digit ratio (more even index and ring finger
lengths) have been reported to exhibit higher
levels of depression, a trait which is more
characteristic of women. We predict that those
men who live the longest will also exhibit more
symmetrical finger lengths. Surprisingly, no
research has been reported that examines such a
relationship.