Elements of Parental Choice: The Evolution of Parental Preferences in Relation to In-Law Selection

Evolutionary Psychology
www.epjournal.net – 2007. 5(1): 70-83
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Original Article
Elements of Parental Choice: The Evolution of Parental Preferences in
Relation to In-Law Selection

Menelaos Apostolou, Department of Psychology, University of Warwick, Coventry, CV4 7AL, UK. E-mail
address: m.apostolou@warwick.ac.uk

Abstract: With the exception of modern post-industrial societies, parents have primarily
been in control of the mating decisions of their offspring. The selection of in-laws has
important fitness consequences for parents. It is hypothesized, therefore, that parents have
evolved specific preferences that enable them to select in-laws that will maximize their
inclusive fitness. To test this hypothesis, data from 297 parents were collected. It is found
that parents place differential emphasis on different in-law traits and that their preferences
vary according to the sex of the in-law. In addition, parents are in agreement when they are
selecting an in-law and their preferences are not contingent upon their sex.

Keywords: parental in-law preferences, parental choice, mating preferences, mate choice
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Introduction

A substantial literature on human mating has been developing in the last few
decades, and which is based on the assumption of free female choice in the mate selection
process over the period of human evolution (i.e., Buss and Barnes, 1986; Buss et al., 1990;
Buss, 1995, 2003; Daly and Wilson, 1983; Gangestad and Simpson, 2000; Symons, 1979,
1989; see also Buss, 2004, 2005 chapters on mating). The theoretical framework of this
literature is based on the parental investment (Bateman, 1948; Trivers, 1972) theory of
sexual selection (Darwin, 1871), which stipulates that the female, by investing more in her
offspring, becomes the scarce resource to which males are seeking access. The female,
therefore, is in the position to exercise choice and to select those males who will maximize
her fitness. It is theorized, for instance, that females have evolved preferences for specific
male traits such as the ability to acquire resources that would be beneficial for them and
their offspring (Buss, 2003; Symons, 1989). Because some of these traits are unobserved, it
is also hypothesized that males have evolved adaptations to reliably signal these traits to
females (Miller, 2000).

This line of reasoning relies on the assumption that males and females are free to
interact with one another when selecting mating partners. However, the ethnographic
record points to a different conclusion. In pre-industrial societies, free mate choice was an
exception to the general rule of mating being controlled by close kin, rather than the
individuals themselves (Broude and Greene, 1983; Frayser, 1985; Stephens, 1963;

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Elements of Parental Choice
Westermark, 1925; Whyte, 1978). It seems, therefore, that free female choice may not be
the appropriate model for studying the evolution of human mating behavior (Cronk, 1991).

By investing more in her offspring, the female becomes a valuable reproductive
resource for males (Trivers, 1972). Parents can then manipulate this resource to maximize
their inclusive fitness (Hamilton, 1964). As mating is a matter of arrangement between
families rather than between offspring, an effective manipulation of the female offspring
also demands a degree of manipulation of the male offspring. Additionally, because males
also provide parental investment, parents have an incentive to control their male offspring.
Furthermore, the large amount and extensive time of parental investment, along with the
fact that parents are physically stronger than their offspring, are some of the reasons why
the former can effectively control the mating of the latter (Alexander, 1974; Flinn and
Low, 1986; Trivers, 1974). However, the offspring are not pawns in the hands of their
parents, and they can evolve adaptations to psychologically manipulate their parents as
well (Trivers, 1974). But parents can also evolve adaptations to counterbalance such
manipulation (Stamps, Metcalf, and Krishnan, 1978). Consequently, the balance tilts in
favor of the parents who can still control parental investment and are still physically
stronger (Dawkins, 1989). Nevertheless, parental choice has its limits and the offspring can
still exercise choice even under strong parental control. Such mating choice can be
exercised mainly within the institution of marriage, where the offspring can divorce the
partners that their parents have selected for them. Extramarital relations is another way by
which offspring choice can be exercised (Apostolou, 2006).


This model of parental choice fits the mating patterns found among modern
foragers. In a sample of 190 such societies, in only 4% of them were individuals free to
select their mate with little or no influence from their parents (Apostolou, 2006). Because
most of human evolution took place when all humans where living as hunters and
gatherers, a period often called the Environment of Evolutionary Adaptness (EEA) (Lee
and DeVore, 1968; Tooby and Cosmides, 1990), a systematic study of modern hunters and
gatherers can provide ecologically valid information for life during that period (Ember,
1978). Consequently, because parental control over female mating is typical of these
societies, it was inferred that parental choice rather than female choice has been the
primary sexual selection mechanism in the humans (Apostolou, 2006).

The evidence from modern foragers places under question the research on human
mating, which is based on the assumption of free female choice. But, a revision of previous
research and the advancement of research require a more thorough understanding and
description of the parental choice mechanism. Towards this objective, the present research
explores the preferences that parents have when they are selecting in-laws.

The evolution of parental preferences


An adaptive problem that parents have to solve is to select in-laws that will
maximize their inclusive fitness. Evolutionary pressures over in-law selection were
substantial during human evolution, because the selection of an in-law could bring
tremendous survival and reproduction advantages to the parents and their family. For
example, in most of the pre-industrial societies, for the marriage to proceed, the son-in-law
gives to the bride’s family a substantial amount of wealth (bridewealth) or works for the
parents for one or two years (brideservice) (Murdock, 1967). Apart from these immediate
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Elements of Parental Choice
benefits, the son-in-law has long-term obligations to provide food and support to his
parents-in-law, sometimes for as long as they live (i.e. the Seri in Central America: Felger
and Moser, 1985, p. 6). Additionally, a marriage is an alliance between families, and such
alliances can bring substantial benefits to the parents and their family. Last but not least,
the selection of an in-law who has high genetic quality, for example resistance to parasites,
or genes that make him or her attractive to the opposite sex, can bring genetic benefits to
the parents in terms of higher survival or reproductive success of their grandchildren.

Potential in-laws vary in all these dimensions (some are hard working, some are
not; some have good genetic quality. some do not, etc.), so they will also differ in their
value as in-laws to the parents. Parents are expected to have evolved preferences for
selecting as in-laws those individuals with the most beneficial traits for them. For example,
parents who have a preference for an in-law who is a good provider are more likely to
choose such an individual, and thus are more likely to acquire a valuable resource for
themselves and their kin. Because of the fitness gain that this preference has generated for
the parents and their kin, it increases in frequency in future generations. Eventually,
parents who have such preferences replace those who do not. Thus, the first hypothesis to
be tested is that parents, when selecting in-laws, have stronger preferences for some traits
and weaker preferences for others.

The second hypothesis to be tested is that parental preferences are contingent upon
the sex of the in-law. Because males and females have different specializations and roles,
parents will value different properties in a son-in-law than in a daughter-in-law. For
example, in the majority of pre-industrial societies, females are responsible for
housekeeping; thus, qualities associated with maintaining a household will be more valued
in a female than in a male. Furthermore, males and females differ in their post-marriage
obligations towards their parents-in-law and this will affect the latter’s preferences.
Because of the asymmetry in parental investment, parents, by controlling their female
offspring, can extract resources from their son-in-law on a long-term basis. They cannot do
the same with their male offspring. It follows that parents will place more emphasis on the
resource acquisition capacities of their son-in-law. Finally, males and females are
biologically different. A female’s reproductive capacity is highly constrained by her age,
but this constraint is much more relaxed in males. Consequently, parents will look for
younger daughters-in-law than sons-in-law.

Parents are expected to differentiate their preferences according to the sex of their
in-law, but their preferences may also be dependent upon their own sex. However, most of
the traits that an in-law may have are equally beneficial to both parents and their kin. It is
hypothesized therefore that parents will not differ in their in-law preferences.
In summary, three main hypotheses are tested: first, parents prefer certain
characteristics more than others in an in-law; second, parental preferences differ according
to the sex of the in-law; and, finally, parents do not differ in their in-law preferences.
Methods

A total of 297 participants, 225 women and 72 men, almost all UK nationals and
residents, completed an online survey. A private company was employed specializing in
recruiting participants for online research in psychology. The participants were selected
from a large database of people willing to participate in online psychological research and
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Elements of Parental Choice
have registered through the company’s web site. The survey was forwarded to those
participants. All parents received payment for completing the survey in the form of credit
(about US$5) that could be used to purchase goods from online stores. Most of the
participants were married (63%), followed by single (16.8%), engaged (10.8%) and
divorced (9.4%). Data from parents with adopted children were included in the survey as
long as they also had at least one genetic child. The age of the children of the participants
was not recorded.

The survey was divided into two parts. In the first part of the survey, demographic
data were collected (Table 1) and then the following hypothetical scenario was given:
“You have two children, one male and one female, and you live in a society where
marriages are arranged. It is your duty as a parent, through negotiations with other parents,
to find an appropriate spouse for both your daughter and your son.” Then, the participants
were asked to rate a set of characteristics in a potential daughter-in-law and son-in-law. In
the second part of the survey, a similar scenario was presented, but the participants rated a
different set of characteristics. Additionally, the participants were asked the following set
of questions: how many grandchildren you desire; how old you would prefer your daughter
to get married; how old you would prefer your son to get married; would you prefer your
son-in-law to be older, younger, same age, no preference, as your daughter; would you
prefer your daughter-in-law to be older, younger, same age, no preference, as your son.

Two instruments were used to assess parental preferences. The first one was
initially developed by Hill (1945) and was later used by Buss et al. (1990) and by Buss,
Shackelford, Kirkpatrick, and Larsen (2001) to assess mate preferences. This instrument
was employed in the first part of the survey in which participants rated 18 characteristics
(see Table 2). Because this instrument was developed to measure mate preferences rather
than in-law preferences, certain adjustments were made. Love and attraction develops
through courtship, but courtship does not exist or it is limited in arranged marriages. Thus,
in the scenario in which parents choose the marriage partners for their offspring, it is not a
valid option for them to choose in-laws on the basis of whether their offspring loves them.
The “mutual attraction-love” item used in previous surveys was dropped because it applies
only when individuals select their own partners. Additionally, the wealth item was added
to test specific hypothesis. Each characteristic was rated in the following four-point Likert
scale: 3 = indispensable, 2 = important, 1 = desirable, but not very important, and 0 =
irrelevant or unimportant.

The second instrument was developed by Buss and Barnes (1986) and is based on a
larger instrument developed by Gough (1973) to study family planning. Additional items
were added to test specific hypotheses, and a “compatibility” item was dropped because it
was not directly applicable in the current research. The final instrument included 16 items
(see Table 3). Each item was rated in the following six-point Likert scale: +2 = very
desirable; +1 = somewhat desirable; 0 = inconsequential, or neutral; -1 = somewhat
undesirable; -2 = very undesirable.

Missing values accounted for no more than 1.5% of the responses for any item. The
missing values were replaced by the mean or the mode (in frequency data) of the series.
Finally, online responses have been found to be as reliable as laboratory-based responses
(Birnbaum, 2000; Kraut et al, 2004).

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Elements of Parental Choice
Table 1
Demographic information for part one and part two of the survey
Males
Females
Total

M SD
M SD
M
SD
Part
One


Age
43.33
11.89 35.41 10.32 37.33 11.22
Number of 2.07 1.07 2.02 1.11 2.03 1.09
Children
Male
1.28 .91
1.12 .80
1.16
.83
Childrena
Female
1.02 .89
1.03 .90
1.03
.90
Childrenb







Part
Two


Age
42.85
11.97 35.48 10.47 37.32 11.30
Number of 2.09 1.14 2.01 1.09 2.03 1.09
children
Male
1.28
.90 1.13 .812 1.17 .84
Childrena
Female
1.08
.89 1.01 .852 1.03 .86
Childrenb
Note. Some participants who completed the first part of the study did not complete the second part, so the
demographics for each sample are presented here separately.
a Three parents in the sample had male adopted children.
b Five parents in the sample had female adopted children.

Results

Not all parents in the sample had children of both sexes. Although there was no
specific hypothesis about whether the sex of the offspring affects parents’ ratings, this is a
possibility. As such, it was tested with a series of ANOVAs and chi-squares, which
indicated that the ratings that parents have given are not affected by the sex of the children
they have.
To assess whether parental preferences are contingent on the sex of the in-law, a
series of paired-sample t-tests was conducted on each item of the two instruments and on
the age items in part two of section two. To examine the importance that parents attach to
the specific items, these items were ranked according to their means. Bonferroni correction
for alpha inflation was applied by decreasing alpha from .05 to .003 (.05/18), two-tailed, in
part one and from .05 to .003 (.05/16), two-tailed, in part two. Also in the sub-section of
part two, alpha was reduced with the same method from .05 to .01 (.05/5), two-tailed.






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Table 2
Means and ranks of preferences concerning potential in-laws for the first part of the
survey

Son-in-law
Daughter-in-law
Rank Characteristics
Mean SD Traits
Mean SD
1
Emotional
stability 2.46
.59 Emotional
stability
2.38
.55
Dependable
Dependable
2
2.45 .61

2.37 .62
character*
character*
3
Good
health
2.03
.65 Good
health
2.06
.66
Desire for home,
4
Pleasing
disposition
1.95
.63

2.03 .80
children
Desire for home,
5
1.91 .80

Pleasing
disposition
1.98 .60
children
Ambition,
6
1.86 .72

Sociability
1.76 .68
industriousness*
Education,
Good cook,
7
1.84 .68

1.68 .79
intelligence*
housekeeper*
Education,
8
Sociability
1.83
.61

1.61 .72
intelligence*
Good financial
Ambition,
9
1.59 .69

1.53 .69
prospect*
industriousness*
10
Refinement*
1.39
.71 Refinement*
1.52
.71
Good cook,
Similar education
11
1.18 .71

1.18 .82
housekeeper*
background
Similar education
Favorable social
12
1.17 .84

1.17 .78
background
status
Good financial
13
Wealth*
1.12 .68

1.16 .68
prospect*
Favorable social
14
1.10 .75

Good
looks*
1.05 .73
status
Similar religious
Similar religious
15
1.08 1.03

1.00 .99
background
background
16
Good
looks*
.90
.68 Wealth*
.92
.67
Similar political
17
.71 .79

Chastity
.74 .89
background
Similar political
18
Chastity
.59 .85

.66 .77
background
* The rating of the trait differs significantly according to the sex of the in-law (p<.003).


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Parental preferences

When selecting in-laws, parents prefer certain traits over others. For both in-laws,
parents place keen emphasis on personality characteristics, such as dependable character
(ranked 1st in Table 2), and kind and understanding (ranked 4th in Table 3). Similarly,
strong emphasis is placed on being employed, which ranks 3rd for the son-in-law and 5th
for the daughter-in-law (Table 3). Perception of compatibility of the in-laws with the
parents also receives a high ranking (4th for the son-in-law and 3rd for the daughter-in-law
in Table 3). Additionally, good health is strongly preferred in an in-law, ranking 3rd for
both in-laws in Table 2 and 2nd in Table 3, again for both in-laws.

Traits associated with resource acquisition abilities, such as industry, intelligence,
financial prospects, and good earning capacity rank near the middle of parental
preferences. Physical attractiveness is among the least preferred characteristics in an in-law
(ranks 16th for the male and 14th for the female in Table 2 and 12 for both in Table 3).
Similarity in education, religion, and political background are at the bottom of parental
preferences (Table 2). Likewise, being religious, and creative and artistic are traits that are
not given much consideration by parents. Finally, being wealthy is ranked low in the
hierarchy of parental preferences, 13th for the son-in-law and 16th for the daughter-in-law
(Table 2).

Sex differences between in-laws

Parental preferences are contingent on the sex of the in-law (Table 4). More
specifically, parental preferences for resource acquisition traits are stronger for a son-in-
law than a daughter-in-law. This is the case in part one of the survey, in which parents
place more emphasis on such traits of the son-in-law, like ambition and industry [t(296) =
2
8.12, p<.001 (two-tailed), ?
p = .182], education and intelligence [(t(296)=6.63, p<.001
2
(two-tailed), ?p =.130)] and good financial prospects [(t(296)=10.79, p<.001 (two-tailed),
? 2
p =.283)]. This is corroborated in part two, in which significant differences were found in
2
good earning capacity [(t(259)=11.35, p<.001 (two-tailed), ?p =.332)], intelligence
2
[(t(259)=3.42, p<.01 (two-tailed), ?p =.043)], and college graduate [(t(259)=6.52, p<.001
2
(two-tailed), ?p =.141)]. Consequently, in most of the traits correlated with resource
acquisition capacity, the son-in-law receives a significantly higher rating than the daughter-
in-law. Also, it seems that it is the potential to acquire resources rather than the resources
per se that matters for the parents. In part one, although parents place more emphasis on
the wealth of the son-in-law than that of the daughter-in-law [(t(296)=5.39, p<.001 (two-
2
tailed), ?p =.090)], wealth ranks low for both in-laws.

Furthermore, to be able to keep a household is valued more in a daughter-in-law
than in a son-in-law. In part one, good cook and housekeeper is more important for the
2
daughter-in-law than for the son-in-law [(t(296)=10.47, p<.001 (two-tailed), ?p =.270)].
This is corroborated in the second part of the survey, in which good housekeeper is also
rated as more important for the daughter-in-law than the son-in-law [(t(259)=7.58, p<.001
2
(two-tailed), ?p =.182)]. Chastity is also valued more in females than males [(t(296)=4.19,
p
2
<.001 (two-tailed), ?p =.056)], but ranks low in the preferences of the parents. In addition,
in part one good looks matter more for females than males [(t(296=4.88, p<.001 (two-
2
tailed), ?p =.075)], but this is not corroborated in part two, because no significant
difference was found for the physical attractiveness item.

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Table 3
Means and ranks of preferences concerning potential in-laws for the second part of the
survey

Son-in-law
Daughter-in-law
Rank Characteristics
Mean SD Traits
Mean SD
Kind and
Kind and
1
1.60 .60

1.58 .59
understanding
understanding
2
Healthy
1.42
.61 Healthy
1.43
.58
Compatible with you
3
Have a job
1.32
.60

1.30 .78
as a parent-in-law
Compatible with you
4
1.30 .76

Easygoing
1.27 .66
as a parent-in-law
Good earning
5
1.30
.65
Have a job
1.21
.90
capacity*
Good family
6
Easygoing
1.29
.58

1.19 .91
background
7
Intelligent*
1.18
.62 Wants
children
1.08
.75
Good family
8
1.13 .91

Intelligent*
1.06 .59
background
9
Wants
children
1.11
.76 Good
housekeeper* 1.05
.66
10
Exciting
personality* .89
.55 Exciting
personality* .80
.58
Good earning
11
Good
housekeeper*
.71 .60

.74 .61
capacity*
12
Physically
attractive .70
.62 Physically
attractive .67
.62
College/University
13
.67 .74

Good
heredity
.54 .69
graduate*
14
Good heredity
.64
.67
Creative and artistic
.51
.64
College/University
15
Creative and artistic
.56
.61

.40 .62
graduate*
16
Religious
.11
.79 Religious
.05
.79
* The rating of the trait differs significantly according to the sex of the in-law (p < .003).


Parents also have different age preferences when they are selecting a son-in-law
than when they are selecting a daughter-in-law (Marginal Homogeneity = 89, p < .001).
When selecting a son-in-law, 17.7% of the parents prefer someone who is older than their
daughter, 28.1% of the same age as their daughter, and 54.2% indicated no specific
preference. There was not a single case of parents preferring a son-in-law who is younger
than their daughter. On the other hand, when selecting a daughter-in-law, 15.8% of the
parents indicated a preference for a younger female than their son, 29.2% for one of the
same age, 54.6% indicated no preference, and there was just one case in which an older
daughter-in-law was preferred. Also, parents prefer their daughters to get married at an
2
earlier age than their sons [t(259) = 6.75, p<.001 (two-tailed), ?p = .150].
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Table 4
A summary of traits that are rated differently according to the sex of the in-law

Differences

Differences
Characteristics
t
Characteristics

(296)
p
? 2 a
t(296) p
? 2 a
Part one
p
Part two
p
Dependable character
3.00 .003 .030 Good earning capacity
11.35 .000 .332
Ambition,



8.12 .000
.182
Intelligent
3.42 .001
.043
industriousness
Education, intelligence 6.63 .000
.130
Good housekeeper
-7.58 .000 .182
Good financial

College/University

10.79 .000
.283
6.52 .000
.141
prospect
graduate
Refinement
-3.29 .001 .035 Exciting personality
3.52 .000 .046
Good cook,



-10.47 .000
.270
Good heredity
3.03 .003
.034
housekeeper
Wealth
5.39 .000 .090



Good looks
-4.88 .000 .075



Chastity
-4.19 .000 .056



a The effect size is indicated here by the partial eta-squared, which is the proportion of total variance
attributable to the within-subjects factor.

Parents want the same

To test whether male and female parents differ in their in-law preferences, a series
of 2x2 mixed ANOVAs was conducted with the sex of the in-law as a within-subjects
factor and the sex of the parent as a between-subjects factor on each item of the two
instruments in each study. In section two of part two, an independent samples t-test was
conducted on the number of grandchildren desired. Also, a 2x2 mixed design ANOVA was
conducted, with the preferred age of the offspring as the within-subjects factor and the sex
of the parent as the between-subjects factor. Finally, a chi-square analysis was conducted
to investigate the association between the sex of the parent and the age of son-in-law and
the sex of the parent and the age of daughter-in-law, respectively. A Kolmogorov-Smirnov
test was conducted on the difference in the ratings of the two in-laws and the sex of the
parent. As before, Bonferroni correction for alpha inflation was applied.

In all the tests that were conducted, the sex of the parent did not achieve statistical
significance, with the only exception of the good looks item in part one of the survey, in
which there was a significant interaction between the sex of the in-law and the sex of the
2
parents [(F(1,295)=10.58, p=.001, ?p =.035)]. Nevertheless, this was not corroborated in
part two, in which no such interaction was found for the physically attractive item. It can
be concluded that male and female parents do not differ in their in-law preferences.
Discussion

In summary, parents have stronger preferences for certain characteristics in an in-
law and these preferences are contingent upon the sex of the in-law. Also, male and female
parents are in agreement on what they are looking for in an in-law.

A possible criticism is that preferences measured here may simply reflect
individual mating preferences rather than parental in-law preferences. Similarly, of course,
it can be argued that given the indication of strong parental control over mating in our
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Elements of Parental Choice
evolutionary past, there was no pressure for mate preferences to evolve. So what was
measured in previous studies on individual mate preferences was in-law preferences. From
the present data, it is evident that in-law and individual mate preferences are distinct. More
specifically, it is known from previous research that males and females differ significantly
in their mate preferences (Buss, 2003). For example, females value earning capacity in a
mating partner more than males. If in-law preferences were simply individual mating
preferences, we would expect that male parents would rate earning capacity in a daughter-
in-law less than female parents would in a son-in-law. In other words, we would expect
significant interactions to exist between the sex of the parent and the sex of the in-law in at
least six items (physical attractive, college/university graduate, good earning capacity,
good looks, good financial prospects, ambition and industriousness), and up to 11 items, as
indicated by previous research (Buss, 2003; Buss and Barnes, 1986; Buss et al., 2001).
With the exception of good looks in the first instrument, such significant interactions were
not found. It has to be then that the in-law preferences measured here are not simply
individual mate preferences.

The results presented here are consistent with an evolutionary framework, but
alternative explanations based, for example, on social learning, cannot be excluded at this
stage, at least not before cross-cultural research has been conducted. More specifically, as
this study is confined to only one culture, the specific cultural contributions in parental
preferences cannot be controlled. Nevertheless, parental preferences have mainly been
optimized by natural selection during the EEA and as such are likely be roughly consistent
across cultures. This prediction awaits further research, but current evidence is consistent
with this prediction. Specifically, parental in-law preferences in the UK are similar to those
among modern hunter and gatherer societies. In hunter and gatherer societies, parents have
specific preferences when they are selecting in-laws. Resource acquisition properties are
important for both in-laws, but more emphasis is placed on those of the son-in-law. When
parents are selecting a son-in-law, they are looking for a good hunter who is industrious
and has a good family background. When they are selecting a daughter-in-law, parents are
looking for an industrious individual from a good family. Parents prefer younger
daughters-in-law and older sons-in-law. Physical attractiveness is less important as a
selection criterion for the parents. Finally, although male parents are reported to have more
decision making power than their wives, when it comes to marriage arrangements, both are
in agreement on their selection criteria (Apostolou, 2006).

Parents may control whom their offspring will marry, but their offspring often have
control over how long the marriage will last. Among hunters and gatherers, divorce, which
applies to both males and females, is almost as universal as marriage (Apostolou, 2006).
Betzig (1989) found that, across cultures, the third most frequent cause of divorce is
cruelty and maltreatment, and bad temper is also frequently reported as a reason for
divorce. There is no point to arrange a marriage that will be dissolved soon after it takes
place. Thus, parents should prefer in-laws with personality characteristics that will increase
the probability of a successful and lasting marriage. A marriage with a kind and
understanding individual, who is emotionally stable and has a dependable character, will
be more successful than a marriage with an individual who does not share these
characteristics. Furthermore, love and attraction between partners is likely to decrease the
probability of divorce. But parents cannot select an in-law based on such properties. What
they can do instead is to select someone with such traits that will make feelings of love and
Evolutionary Psychology – ISSN 1474-7049 – Volume 5(1). 2007. -79-

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