Polyester aside, the disco dancers of the ’70s may have been on to something.

According to a new study that used motion-capture technology to analyze and accurately recreate the moves of dancing Jamaican teens, people appear able to pick genetically superior partners based on the way they dance.

The research, done jointly by computer scientists at the 91̽»¨and anthropologists at Rutgers University, represents the first time scientists have been able to link skillful dancing to established measures of human desirability and attractiveness.

The work appears as the cover story in Thursday’s issue of the journal Nature.

“This suggests a completely new way in which dance will be looked at and analyzed in the future,” said Zoran Popović, associate professor in the 91̽»¨Department of Computer Science & Engineering and a co-author of the study. “It’s the first time it has been shown that people can discern genetic quality from dance and movement itself.”

The project also opens a new chapter in the use of motion-capture technology and computer animation, Popović’s primary fields of study. The techniques have been used in rehabilitative and sports medicine and, more familiarly, in creating feature movie animations and special effects.

“But use of motion capture as a tool for analysis and archiving of movement in indigenous cultures has not been attempted — this is the first time it’s really been taken into the field and used as an anthropology tool,” he said. “So there is excitement not only in terms of scientific discovery, but also in terms of having a new scientific tool that can answer many questions pertaining to human movement and its role in human evolution and society.”

In conducting the study, researchers traveled to Southfield, Jamaica, where dance is culturally important to both sexes. That area also has a group of youths whose development has been tracked for body symmetry over the past decade. Evolutionary biologists have established close links between symmetry and such traits as longevity, strength and reproductive success in many animal species, including humans.

The researchers analyzed 183 members of that group, age 14 through 19, attaching infrared markers to the teenagers at 41 body locations. They filmed each teen for one minute, dancing to the same popular song, with special cameras that tracked the markers to record in detail how the dancers moved.

Popović and his colleagues processed that raw data to create dancing animations that duplicated the movements of the dancers. They then asked teen peers to evaluate how well the computer-generated figures danced. The figures were the same size, faceless and gender-neutral so evaluators had to base their answers on movement rather than other considerations, such as physical attractiveness.

The study showed that the dancers who rated best tended to be those with greater body symmetry. And symmetry is correlated with better genes, Popović said.

`”At least since Darwin, scientists have suspected that dance so often plays a role in courtship because dance quality tracks with mate quality,” said Lee Cronk, associate professor of anthropology at Rutgers and project leader. “By using motion-capture technology, we can confidently peg dancing ability to desirability.”

Scientists also broke down the results by gender. They found that symmetrical men scored better than symmetrical women, and that female evaluators rated symmetrical men higher than male evaluators rated symmetrical men.

That’s not surprising, according to William Brown, Rutgers postdoctoral research fellow and a study co-author.

“In species where fathers invest less than mothers in their offspring, females tend to be more selective in mate choice and males therefore invest more in courtship display,” Brown said. “Our results with human subjects correlate with that expectation. Attractive men are putting on a better show, and women are noticing.”

In addition to Popović, Cronk and Brown, co-authors of the study include graduate student Keith Grochow and recent doctoral graduate Karen Liu, of the UW; and professor Robert Trivers and graduate student Amy Jacobson of Rutgers.

The work was supported by Rutgers and the UW, the Ann and Gordon Getty Foundation, the Biosocial Research Foundation and the National Science Foundation.

Polyester aside, the disco dancers of the ’70s may have been on to something.

According to a new study that used motion-capture technology to analyze and accurately recreate the moves of dancing Jamaican teens, people appear able to pick genetically superior partners based on the way they dance.

The research, done jointly by computer scientists at the 91̽»¨ and anthropologists at Rutgers University, represents the first time scientists have been able to link skillful dancing to established measures of human desirability and attractiveness.

The work appears as the cover story in Thursday’s issue of the journal Nature.

“This suggests a completely new way in which dance will be looked at and analyzed in the future,” said Zoran Popović, associate professor in the 91̽»¨Department of Computer Science & Engineering and a co-author of the study. “It’s the first time it has been shown that people can discern genetic quality from dance and movement itself.”

The project also opens a new chapter in the use of motion-capture technology and computer animation, Popović’s primary fields of study. The techniques have been used in rehabilitative and sports medicine and, more familiarly, in creating feature movie animations and special effects.

“But use of motion capture as a tool for analysis and archiving of movement in indigenous cultures has not been attempted — this is the first time it’s really been taken into the field and used as an anthropology tool,” he said. “So there is excitement not only in terms of scientific discovery, but also in terms of having a new scientific tool that can answer many questions pertaining to human movement and its role in human evolution and society.”

In conducting the study, researchers traveled to Southfield, Jamaica, where dance is culturally important to both sexes. That area also has a group of youths whose development has been tracked for body symmetry over the past decade. Evolutionary biologists have established close links between symmetry and such traits as longevity, strength and reproductive success in many animal species, including humans.

The researchers analyzed 183 members of that group, age 14 through 19, attaching infrared markers to the teenagers at 41 body locations. They filmed each teen for one minute, dancing to the same popular song, with special cameras that tracked the markers to record in detail how the dancers moved.

Popović and his colleagues processed that raw data to create dancing animations that duplicated the movements of the dancers. They then asked teen peers to evaluate how well the computer-generated figures danced. The figures were the same size, faceless and gender-neutral so evaluators had to base their answers on movement rather than other considerations, such as physical attractiveness.

The study showed that the dancers who rated best tended to be those with greater body symmetry. And symmetry is correlated with better genes, Popović said.

“At least since Darwin, scientists have suspected that dance so often plays a role in courtship because dance quality tracks with mate quality,” said Lee Cronk, associate professor of anthropology at Rutgers and project leader. “By using motion-capture technology, we can confidently peg dancing ability to desirability.”

Scientists also broke down the results by gender. They found that symmetrical men scored better than symmetrical women, and that female evaluators rated symmetrical men higher than male evaluators rated symmetrical men.

That’s not surprising, according to William Brown, Rutgers postdoctoral research fellow and a study co-author.

“In species where fathers invest less than mothers in their offspring, females tend to be more selective in mate choice and males therefore invest more in courtship display,” Brown said. “Our results with human subjects correlate with that expectation. Attractive men are putting on a better show, and women are noticing.”

In addition to Popović, Cronk and Brown, co-authors of the study include graduate student Keith Grochow and recent doctoral graduate Karen Liu, of the UW; and professor Robert Trivers and graduate student Amy Jacobson of Rutgers.

The work was supported by Rutgers and the UW, the Ann and Gordon Getty Foundation, the Biosocial Research Foundation and the National Science Foundation.

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For more information, contact Popović at (206) 543-4226 or zoran@cs.washington.edu.

The Dance Symmetry Project Web site, which includes video clips of dancing animations, can be found here:

A three-member team of 91̽»¨ students — all local residents and all products of public education — have taken top honors in an international mathematics competition, beating teams from such math powerhouses as MIT, Yale and the University of California, Berkeley.

Again.

It’s the fourth time in three years that the 91̽»¨has placed an undergraduate team in the rarefied top-tier of the Consortium for Mathematics and Its Applications’ annual Mathematical Contest in Modeling. Of this year’s 599 participating teams, just seven, including one from the UW, were judged to be outstanding winners.

“This is just phenomenal that we had another winner this year,” said mathematics Professor Jim Morrow, who acted as adviser for the four 91̽»¨teams that entered the 2004 contest. “We’re very pleased to have such consistently good students. They’re top-notch mathematicians.”

The winning team members are Tracy Lovejoy of Kenmore, Sasha Aravkin of Bothell and Casey Schneider-Mizell of Olympia. All are seniors.

Last year, the 91̽»¨placed two teams in the top category. It was the first time in the then 19-year history of the competition that one university had teams win for both problems that comprise the contest.

In a way, the 91̽»¨had a second win this year as well, said Selim Tuncel, chairman of the mathematics department. A member of one of last year’s winning Husky teams, Bellevue native Jeff Giansiracusa, is now at Oxford University in England as a graduate student. He coached this year’s Oxford team, which joined the 91̽»¨as one of the seven champions.

The contest began at 5 p.m. on Feb. 5, when officials posted two problems on the Web. The teams had until 5 p.m. on Feb. 9 to select one problem and devise a solution. Competitors could access sources on the Web or in the library, but could not consult with anyone outside their team.

Morrow arranged for the teams to have 24-hour computer access and isolated spaces to do their work. But once the four-day contest started, they were on their own.

“At the beginning I think we all felt a little pressure because the 91̽»¨had won two years in a row,” Lovejoy said. “We didn’t want to be the ones to break that.”

When the problems were posted, Aravkin said the group debated for a couple of hours over which to attempt. One involved mathematically assessing how unique fingerprints are. The other dealt with lines at amusement parks, and students were tasked with constructing a way to manage the lines that would be efficient and fair to customers. The fingerprint problem seemed more interesting and there were lots of available data — too much data, as it turned out. The task of wading through and sifting all the information seemed daunting given the tight deadline, Aravkin said, so the three decided on the second problem and got to work.

But they soon ran into the opposite problem.

“It’s amazing how little useful data there is on amusement parks,” Aravkin said. “There are a lot of advertisements, but nothing that would be useful to a mathematician.”

Later, group members said, they realized that the dearth of information was probably intentional — amusement parks don’t want competitors to know which of their rides is the most popular and how they manage their crowds.

The group was in a spot, Lovejoy said. He and his teammates needed data, fast.

It was about lunchtime, so he headed to the Husky Den cafeteria in the Husky Union Building. Not to eat, but to watch the lines at the Pagliacci Pizza and Subway sandwich franchises.

“That was all I could think of,” he said. “I counted the number of people in line every minute. I was there for about 20 minutes.”

When Lovejoy got back, they put the data in a graph and it jibed well with the theoretical models they had constructed.

“That was more or less the only real data we had,” he said. “The fact that we went the extra mile to get real data may have been one of the things that set us apart.”

Even though all three of this year’s winners are graduating, the prospects for next year’s contest are good, Morrow said. Two of the other three 91̽»¨teams that competed achieved a meritorious ranking, putting them in the top 10 percent of participants. And only one member of those teams is graduating.

“I think we stand a good chance of continuing our streak,” Morrow said.

Lovejoy agreed.

“They’ll do great,” he said. “They have the advantage of having done it before, they’ll have a better idea of what the judges are looking for, and they are very creative people. I know all of them well.”

All three of the 2004 winners are mathematics majors, each with an additional focus: Schneider-Mizell and Lovejoy are also in the physics program, and Aravkin is studying computer science.

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For more information, contact Morrow at morrow@math.washington.edu, or Tuncel at tuncel@math.washington.edu.

Information about the competition, including the problems contestants attempted to solve and overall results, are available at

Information on the local teams, including copies of the winning papers, is available at