1. Reham
Jalal
-‐
1
1
A
comparative
study
of
racial
preference
for
mate
choice
in
multicultural
vs.
monocultural
communities
Abstract
A comparative study for finding the difference of racial preference in mate choice was
conducted. The results observed, demonstrated that multicultural communities asserted mostly to
disassortative mating. Whereas, monocultural communities mostly showed positive assortative
mating. Differences between the two groups were statistically relevant with p value – 0.02 (chi-
squared test, df =1, p-value = 0.0289). Further, biological causation for these differences were
explained through the evolutionary perspective of increasing Darwinian fitness.
Introduction
Preference in mate choice has been of interest since Darwin’s evolutionary theory of
fitness. In which, natural selection favours the most “fit” traits from a wide variety of genotypes
(genes) and phenotypes (expressed genes). In particular, those that contribute to the highest
survivability and fecundity (reproduction) of an organism. Fitness could also be branched out into
inclusive fitness, where it is measured not only through individual success of survivability and
fecundity, but those of related kin as well (Smith 1978). A lot of behavioural patterns of humans,
have evolved from this. For example: altruism, the “selfless” care of parents towards their
offsprings. This is understood as proper care of ones oung ensures their survivability until age of
fecundity. This in turn maximizes parental fitness, as it increases the likelihood of passing their
genes onto subsequent generations (Wilson 1975). Another interesting behaviour is positive
assortative mating, where individuals select their potential partners based on similarity of traits.
(Beckman and Elston 1962; Spuhler 1968). Some selective traits as seen from social studies
include ethnicity, religion, socioeconomic status (Burgess and Wallin 1953; Kalmjin 1998).
However, race and ethnicity in particular, is of most interest in evolutionary biology, as they can
be explained through natural selection working towards increasing inclusive fitness (Thiessen and
Gregg 1980). Individuals select to mate within the same race or ethnicity, because they share the
most similar phenotypic traits, and it becomes advantageous for both the partners. As similarity
in phenotypic traits often mean they have underlying same genes, this increases their relatedness
to each other, therefore also enhances replicate genetic transmission to their offsprings at a
reduced reproductive cost (Jiang et al. 2013). However, in nature, this is not entirely the case, as
we see excessive inbreeding, specially those with the closest of genes (ex. nuclear families) leads
2. -‐
2
to he onset of the opposing vectoral force of negative assortative mating (Lindzey 1967). This is
because, excessive homozygosity in genes can in turn lead to deleterious effects in alleles which
are lethal and reduce fitness. Therefore, natural selection favours the evolutionary stable choice
of homogamy, in which ethnicity is a good indicator of genes which are not exactly similar yet,
related. That at the end results into optimal genetic transmission in the subsequent generation,
while co-currently avoiding inbreeding depression (Thiessen and Gregg 1980).
However, in the past decades, globalization of the world through migration and exposure
of varied cultures to each other with advances in technology such as internet, raises questions of
this natural pattern of assortative mating. As, different cultures reach a more communal ground,
and reduce cultural gap (Adam et al. 1997), role of ethnicity might be less impacting in
assortative mating. Recent study done by Chiswick and Houseworth 2009, on the US census for
studying the patterns of ethnic intermarriages amongst immigrants and locals, have found that
frequency of inter-cultural marriages were greater in older immigrants than recent. To support
this, another assessment done on second generation Sweden immigrants, also showed an
increased pattern of inter-ethnic marriages, so long other selective factors such as education
remained constant (Celikaksoy et al. 2010). Both these findings are based on social sciences
studies and no biological causation were given. Therefore, I would like to explore this idea
further under evolutionary perspective, and test whether individuals who were specifically raised
in multicultural communities would still assert to positive assortative mating, similarly to those
who lived in monocultural communities. Regardless, of their variant exposure to different races
and communal upbringing, because of the evolutionary importance of increasing genetic
homology between parents and offsprings.
Methods
This study was done by taking a survey for preferred choice of ethnicity for a committed
and long-term partner/spouse, amongst two groups of individuals as follows: 1) Individuals raised
in a multicultural community. 2) Individuals raised in a monocultural community. For testing the
following hypotheses:
Ho - There is no difference of preferred mating pattern (assortative/disassortative) within
the two communities.
HA - There is a significant amount of difference in the preferred mating pattern
(assortative/disassortative) within the two communities.
All participants consented in sharing their information for the study and remaining
anonymous. The subjects were randomly sampled from the diverse campus of University of
3. Reham
Jalal
-‐
3
3
Calgary in person, and then by advertisements online in Canadian public forums. Canada is an
ideal place for studying effects of multiculturalism because 20.6% of their population are
residents who are born outside Canada (Statistics Canada 2011). Similarly, for sampling subjects
from monoculture communities, individuals, who moved recently to Canada and lived in a
monocultural environment most part of their lives were locally surveyed. Along with those that
never moved out of their countries were surveyed through Google Poll. To reduce confounding
variables, preferred choice for ethnicity were asked exclusively, discounting correlation of other
traits such as socioeconomic/educational status, religion/political views and differences in
responses from genders. Further all the sampled individual participants were restricted from ages
18-35 to ensure similarity in maturity levels for making independent life choices. All the
collected data from the two communities, were further classified by assortative and disassortative
mating, as represented by the dummy table below.
Table 1: Dummy table for preferred choice for mating amongst multicultural and
monocultural communities.
Since, differences of preferred mate choice within the two communities, are independent
categorical variables, it met the assumption of a chi-squared test, which was picked for statistical
analysis. As, we have four levels of measurement (assortative~multicultural;
disassortative~multicultural and assortative~monocultural; disassortative~monocultural) more
than 20 (minimum sample size = 4 cells x 5 ) were sampled, with total sample size being N= 73.
Lastly, the statistical test was done through R-Project for Statistical Computing.
Results
All the experimental results were collected from the raw data (Appendix Table 1a & b)
and inserted into the contingency table below, for demonstrating the differences in proportion
within the two measurement groups. Also, pie charts showing percentages of specific preferences
Multicultural Monocultural
Assortative Mate Choice (Ethnicity)
Dissassortive Mate Choice (Ethnicity)
4. -‐
4
for mating within the two groups, which were further classified to assortative and disassortative
mating are demonstrated in Fig 1a and b, respectively.
Multicultural Monocultural Total
Assortative Mate Choice (Ethnicity) 20 18 38
Disassortative Mate Choice
(Ethnicity) 27 8 35
Total 47 26 73
Table 2: Contingency table for preferred choice for mating amongst multicultural and
monocultural communities.
Figure 1a: Pie chart showing percentage of specific preferences of race in mate choice within the
two communities.
5. Reham
Jalal
-‐
5
5
Figure 1b: Pie chart further classifying the different percentage of data. In particular all that were
same race, and same or similar race were grouped under assortative mating. Likewise, those that
were different or open to any race were classified under disassortative mating .
As observed from the results above, multicultural communities had a more variant
response than monocultural communities. Whereupon they showed above 50% of their
population preferring absolute disassortative mating. Followed by 22.4% of the population
showing absolute assortative mating. Further 14.3% showed same or similar race preference and
even a smaller 10.2% preferring an absolute different race. On the other hand, monocultural
communities were less variant as 65.7% preferred absolute assortative mating. Followed by
25.7% asserting to absolute disassortaitve mating. The rest 8.6% were same or similar and
different race. Together, the total percentage of disassortative mating (open to any race or
different race) in multicultural and monocultural community were found to be 57.4 %, and
25.7% respectively. And total percentage of population asserting to assortative mating (same race
and same or similar race) were 69.2%in monocultural communities and 42.6% in multicultural
communities.
Lastly, the differences in these results were proven by the chi-squared test, which showed
there was a statistically significant difference of preferred mate choice within multicultural and
monocultural communities. With only 2% probability of the observed results solely occurring by
chance. Therefore, we safely reject null hypotheses (chi-squared test, df =1, p-value = 0.0289).
6. -‐
6
R-output
Pearson's Chi-squared testdata: selective
X-squared = 4.7735, df = 1, p-value = 0.0289
Discussion
The results showed that individuals raised in monocultural communities are significantly
less reluctant to pick partners with dissimilar racial characteristics, and more inclined to
assortative mating than those raised in multicultural communities. This rejects the null hypothesis
which stated that both the communities should have shown similar assortative mating pattern.
These results are best understood as most factors such as lifestyle, education, socioeconomic
status, are homogenous in monocultural communities, costs of fitness for both parent and
offspring are more strongly affected with increase in homology of the gene loci alone. On the
other hand, in multicultural communities, phenotypic similarity in traits play a less significant
role in mating selection. Because, although mating with those with dissimilar genetic traits
decreases similarity of parents with their offspring, inclusive fitness which also depends on the
fitness of the offspring is unaffected or even so maximized. This is because there are plenty of
other factors in a multicultural environment that are non-homogenous with the parent culture, so
the parents must work towards minimizing those differences for better chance of offspring
survivability. For example, newcomers who come to this new culture, do their best to assimilate
to it. Mating with someone of this foreign culture, not only increases the relatedness of the
newcomer in this new population socially, but also makes the offspring biologically relate to the
locals genetically. In turn decreasing perhaps unbeneficial intercultural sensitivity which could
(Bennett 1986) have negative effects on offspring survivability. Further, this point could be
explained if seen from an evolutionary perspective where natural selection works towards
reducing phenotypic variances within an entire population (Kingsolver et al. 2001). So, for
parents who selected partners with significantly dissimilar phenotypic traits than themselves but
those who are closer to the genetics of the major population, they were in turn acting towards
creating a more refined homozygous gene pool for the entire population, in the subsequent
generations. Another interesting reason could be seen in patterns of preferences that 14.3%, of the
sampled population for assortative mating from multicultural community showed, whereupon
7. Reham
Jalal
-‐
7
7
people preferred if not partners of their own race but genetically closer races than the extreme
foreign. For example, a significant amount of south east asians preferred arabs, or other related
races over caucasians or far east Asians (Appendix 1a). This shows partial positive assortative
mating, where individuals didn’t choose individuals with completely dissimilar phenotypic traits,
but those who showed closer phenotypic similarity from a set of really heterozygous options.
Thus, still abiding by the law of natural selection for maximising fitness.
Conclusions
Overall, a successful experiment was done in showing the differences in the pattern of
mating within multicultural and monocultural communities. There was a significantly greater
chance of disassortative mating in multicultural communities and a greater chance of assortative
mating in monocultural communities. These differences were statistically relevant (chi-squared
test, df =1, p-value = 0.0289). Further, biological causation of this were explained to be due to
increasing overall Darwinian fitness in both communities. Whereupon, multicultural communities
benefitted by reducing phenotypic variances of the gene pool within the entire population by
disassortative mating. And monoculttural communities benefitted by increasing inclusive fitness
through assortative mating. This experiment could be further expanded to other areas in the world
and see if similar patterns are seen.
Acknowledgements
I would like to give my acknowledgements to all the participants in the study.
Specifically, to the local students of University of Calgary and international participants from the
regions of Southeast Asia, Middle East and Australia. All of whom, wilfully consented on being
surveyed. Professor JingJing Wu, from the department of Mathematical Science, U of C, under
whose supervision I was able to conduct this study. Lastly, my peers in the Faculty of Science, for
proof-reading my paper and giving me constructive feedback, without whose assistance I would
not have been able to produce this work.
8. -‐
8
Literature Cited
Adam N, Awerbuch B, Slonim J, Wegner P, Yesha Y. 1997. Globalizing business,
education, culture, through the internet. Communications of the ACM. 40(2).
Lindzey G. 1967. Some remarks concerning incest, the incest taboo, the psychoanalytic
theory. American Psychologist. 22:1051-1059.
Bennett MJ. 1986. A developmental approach to training for intercultural sensitivity.
International Journal of Intercultural Relations. 10(2): 179–196.
Burgess EW, Wallin P. 1953. Engagement and Marriage. Philadelphia: Lipincott. pp:
819.
Celikaksoy A, Nekby L, Rashid S. 2010. Assortative mating by ethnic background and
education among individuals with an immigrant background in Sweden. Journal of
Family Research. 22: 65-68.
Chiswick BR, Houseworth C. 2011. Ethnic intermarriage among immigrants: human
capital and assortative mating. Review of Economics of the Household. 9(2): 149-180.
Immigration and Ethnocultural Diversity in Canada. 2011. National Household Survey.
Statistics Canada. Catalogue number: 99-010-X2011001.
Jiang Y, Bolnick DI, Kirkpatrick M. 2013. Assortative mating in animals. The American
Journalist. 181(6).
Kalmjin M. 1998. Intermarriage and Homogamy: Causes, Patterns and Trends. Annual
Review of Sociology. 24: 395-421.
Kingsolver JG, Hoekstra HE, Hoekstra JM, Berrgan D, Vignieri SN, Hill CE, Hoang PG,
Beerli P. 2001. The Strength of Phenotypic Selection in Natural Populations. The
American Journalist. 157(3).
Smith JM. 1978. Optimization Theory In Evolution. Annual Review of Ecology,
Evolution and Systematics. 9: 31-56.
Spuhler JN. 1968. Assortative mating with respect to physical characteristics, Eugenics
Quarterly. 15(2): 128-140. DOI: 10.1080/19485565.1968.9987763
Beckman L, Elston R. 1962. Assortative mating and fertility. Acta Genetica Sinica.
12:117–122.
Thiessen D, Gregg B.1980. Human assortative mating and genetic equilibrium: An
evolutionary perspective. Ethology and Sociobiology. 1(2): 111-140.Wilson EO. 1975.
Sociobiology. Cambridge: Harvard University Press.
