Study indicates mixed race, physical symmetry correlate
By David Zisser
Nov. 3, 2002 9:00 p.m.
A recent study by UCLA Assistant Adjunct Professor of Biology
Jay Phelan concluded that biracial people are perceived as more
attractive than “uniracial” people because they have
more symmetric features.
Symmetry, according to Phelan, reflects an organism’s
developmental stability and is strongly associated with longevity,
health and fitness.
Small random deviations from perfect symmetry in bilateral
traits such as hands, ears and feet result in what is termed
Since only one gene codes for both the left and right side of an
organism, the two should, theoretically, be identical ““ or
If they are not identical, something has gone wrong, according
Asymmetries, then, can be viewed as developmental noise.
“The gene instructions are not being played out the same
way for both sides,” Phelan said.
There are two reasons for asymmetry. Either the gene is
imperfect or the environment was tough, making proper development
An example of the environment’s effect on development is
fetal alcohol syndrome, which can result in a 3 to 4 percent
difference on both sides of the body, according to Phelan.
Symmetry, he found, was greater in heterozygous organisms. In
other words, organisms are more symmetrical ““ and therefore
potentially more “fit” ““ when their genes have
two different alleles (for instance, one dominant allele and one
recessive allele rather than two dominant or two recessive
Crossing organisms from different populations, he believed,
would result in “hybrid vigor.” The theory was that
their heterozygosity was making them stronger and healthier.
Genes produce enzymes that assist in bodily processes. When two
slightly different enzymes are produced by heterozygous genes, the
organism is “covered under a wider range of
conditions,” he said.
Most humans are heterozygous in about 20 percent of their
Assuming that biracial people are more heterozygous since they
come from different populations (despite the debate surrounding the
relative amounts of genetic variation within and among
populations), Phelan started by measuring the symmetry of 99 UCLA
student volunteers who were either biracial or uniracial.
Biracial people were defined as those whose mother and father
were of different races, but each of their parents were uniracial.
Both parents of the uniracial subjects were of the same race.
Phelan’s study concluded that biracial people were
significantly more symmetrical than “uniracial” people.
All 25 of the least symmetrical subjects were from uniracial
groups, which were either Asian, black, Hispanic or white. Seven of
the eight most symmetrical subjects were from biracial groups
(Hispanic-white, Asian-white, black-white or Asian-Hispanic).
In addition, Phelan found that symmetry was about the same for
all uniracial people no matter which group they were in, and about
the same for all biracial people, regardless of racial
Phelan, however, did not want to stop merely with symmetry. He
hypothesized that those who were more symmetrical would also be
perceived as more attractive.
To determine attractiveness, 30 people then rated photos of the
subjects who had been measured for symmetry on attractiveness,
ranking them from one to seven (seven being the highest).
The results: Biracial people were perceived as significantly
more attractive than “uniracial” people.
According to Phelan, this means that symmetry, and its
correlate, attractiveness, are indications of fitness.
They are important for reproductive success because people are
selected as mates partly based on such characteristics.
Becky Sweet, a fourth-year molecular, cell and developmental
biology student, participated in the study as a first-year because
it was a fundraiser for her sorority.
“Biracial people have certain disadvantages, (so)
it’s nice to know we have certain advantages as well,”
said Sweet, who is half Filipino and half white.
While she finds the research interesting, Sweet hopes that it
will lead to more scientific studies.
“What genes control symmetry?” she asked as a
potential research question.
The fact that biracial people are more symmetrical and
attractive is “a nice conclusion,” she said, “but
Emily Shin, a third-year psychology student and president of the
UCLA Hapa Club, also appreciates Phelan’s work.
“I think that it’s really great that people are
doing research on hapa people, generally a group that’s
marginalized,” Shin said.
She added, however, that there is some dissent in the hapa
community about research like Phelan’s, which perpetuates the
stereotype that hapas are on average, more attractive people.
“It makes hapa people, especially hapa girls, feel very
objectified,” Shin added.
Like Sweet, Shin expressed interest in what kind of studies will
come out of Phelan’s work.
Phelan is well aware of the controversy surrounding his work,
particularly his use of race as a category for grouping
In the meantime though, Phelan hopes to follow up on his work by
looking at the parents of his subjects for this study.
He hopes to confirm that the parents are of normal symmetry, and
not symmetrical anomalies, in order to validate the idea that
heterozygosity is responsible for the increased fitness and
symmetry of biracial people.