INTERPERSONAL RELATIONS AND GROUP PROCESSES

DAVID T. LYKKEN AND AUKE TELLEGEN

time when the respondent first concluded that the spouse
would be her or his choice. If mate selection is a lawful process,
then the same individual who has recently selected one of a pair
of MZ twins ought to feel at that time a substantial attraction to
the MZ cotwin. If mate selection depends on some set of rather
general demographic, physical, and psychological characteris-
tics of the chosen (as well as on the characteristics of the
chooser which, in this case, are held constant), then the fiancee
or fiance of one DZ twin, similarly, ought to feel a weaker but
significant bias in favor of the DZ cotwin who shares half his or
her spouse-to-be’s genes plus family environment, ethnicity,
and socioeconomic status.

Method

A slightly different questionnaire was sent in the same mailing with
the Choices questionnaire to each twin’s spouse. This also included
five questions with five answer alternatives. The first three questions
asked each spouse to compare the twins’ choices in clothing, house-
hold furnishings, and vacations, just as in the twins’ own question-
naire. The spouses also were asked to evaluate the twins’ similarity in
their choices of friends. Finally, each spouse was asked to report his or
her feelings about their spouse’s cotwin when they first got acquainted.
Once again, confidentiality was emphasized and the spouses were
asked not to show their answers to their twin spouse but to seal them in
a provided envelope and return them to us. The data were analyzed as
for the previous questionnaire and are presented in Table 5.

Results

The data in Table 5 generally confirm the proposition that
MZ twins tend to be similar in most of their choice behavior,
not only by their own report but also as reported by a spouse.
There are some differences. Male twins, according to their
wives, are not as similar in their choices of household furnish-
ings as female twins are reported to be by their husbands. It
seems reasonable to infer that wives tend to have more say in
household furnishing than husbands do. Conversely, male twins
are more similar than female twins in their choice of vacations,
at least as reported by their respective spouses. We infer that, in
this population, the men tend to have more say than the women
do in selecting vacation activities. The spouses of both sexes
consider that the MZ twins tend to have a preponderance of
similar friends, and fewer spouses of MZ than of DZ twins rate
the twins’ friends as dissimilar.

On the question about mate selection, we find two striking
differences from the results in Table 4. The first, that nearly

Table 5

Percentages of Evaluations by the Spouses of Adult Twins of the Similarity in the Twins’ Choice
of Clothes, Household Furnishings, Vacation Activities, and Friends

and the Spouses’ Attitudes Toward Their Spouse’s Cotwin

Note. I = Percentages rating “similar” vs. “dissimilar” or “liked” vs. “disliked” differ at p < .05 by
chi-square test. > or < = monozygotic (MZ) and dizygotic (DZ) percentages differ at p <. ,05.

• Scale was almost identical-quite similar-average-not similar-very different-can’t answer. “Similar” =
percentage of respondents choosing the first two alternatives; “dissimilar” = percentage choosing not
similar or very different. ^b Scale was could have fallen for my twin-in-law-really liked my twin-in-law-no
strong feeling-would not have chosen my twin-in-law-would rather have stayed single-can’t answer.

“Liked” = percentage of respondents choosing could have fallen for my twin-in-law or really liked my
twin-in-law; “Disliked” = percentage choosing would not have chosen my twin-in-law or would rather have
stayed single.

<<   <   6   7   8   9   10   11   12   >   >>