WHEN Yao Xueqiang married an ethnic Paijiao woman after leaving the army more than 20 years ago and settling in her Mangang Village, the marriage was the beginning of the Han man's bonding to her tribe.

And that knot was tied by his needlework: Yao, the only tailor in the village, has helped preserve the traditional costumes of this almost-unknown ethnic tribe in China.

Mangang Village, with fewer than 180 Paijiao people, is secluded in thick tropical forests in Mengla County of southwest Yunnan Province near the border with Laos.

But seclusion has not protected it from waves of modernization that began to sweep China in the early 1980s. Along with highways, televisions and telephones came cheap colorful cotton and polyester clothing.

As a result, weaving and sewing were no longer essential and, except for festivals and special occasions, costumes were abandoned in favor of store-bought clothes.

Yao's arrival, however, made a difference. A soldier stationed with frontier defense troops only two kilometers from Mangang, Yao met Yila, his wife-to-be, during his trips to the village to buy vegetables for the garrison.

After their wedding, they returned to Mangang after spending six months in Yao's hometown in Sichuan Province. Yila was afraid that her brothers could not take proper care of their parents and wanted to return home.

Yao's mother-in-law's clothes were almost the only models that Yao had when he decided to try a different design for the traditional costumes of the Paijiao.

Instead of the traditional, loose raglan sleeve, he made more fitted sleeves that are technically more difficult. He also reproduced the traditional costumes for Paijiao men based on his father-in-law's description.

Yao, age 45, became a popular tailor and in time he was the only tailor making traditional Paijiao costumes in Mangang.

As a result of Yao's suggestion and design, the Paijiao people - who worship oxen - are now wearing horn-like headwear, instead of coiling their hair into the traditional horn shape, which is time-consuming and has now been abandoned.

Little is known about the tribe and occasional media reports describe them as mysterious. It has no written language but a code of symbols that is becoming forgotten.

According to legend, an unmarried Paijiao girl was driven from her home by her parents because she was pregnant. She gave birth to a boy on the mountain. The cry of the baby attracted a cow, which nursed the newborn.

To pay homage to his bovine savior, the boy coiled his hair into a horn shape, and other tribe members followed.

This is why the tribe is called Paijiao, which means a pair of horns.

Yao doesn't consider his work cultural preservation.

"I did it because I learned tailoring and was interested in costumes," he says.

Yao's traditional clothing is only worn on festive occasions and shirts, skirts, trousers, jeans and sweaters are commonly worn today.

Even Yao's father-in-law, Boben, who is in his 70s, wears a dark gray shirt, pants and a navy-blue baseball cap. He looks just like an elderly Han man, except for his sun-tanned skin.

Yao's 44-year-old wife Yila wears close-fitting shirts with short sleeves and long, straight colorful skirts, typical of the women of the Dai ethnic group of Xishuangbanna, the prefecture that administers Mengla.

If no one succeeds Yao - the last tailor - there will be no one making traditional Paijiao costumes.

Both of his sons have different futures in mind. His eldest, 19-year-old son left Mangang three years ago and now works at a shoe factory in Chengdu, Sichuan. The other son, Yao Chu, who is taller than 1.8m, wants to become a fashion model, but not of Paijiao costumes.

"I've never worn traditional Paijiao clothes. I don't think they look cool. I like trendy, fashionable clothes," says the young man who is half Paijiao, half Han.

In China, a child born of a mixed marriage between two ethnic groups can choose either ethnic identity of the parents. If the choice is between a Han and a minority, parents usually choose minority status for the child who can enjoy preferential policies in education and family planning.

The eldest son left home after middle school because he wanted to be independent and experience urban living. He worked in a Beijing garment factory before going to Chengdu last year.

He isn't concerned about losing the traditions of his community, saying that if he forgets his Paijiao mother tongue, his peers will carry on.

His grandfather Boben, however, is sad that young people show so little interest in their heritage. He says few can play the traditional bamboo musical instrument, the qike, let alone play it in festival rituals and perform historical sagas.

Boben says the Paijiao people in Mangang are migrants, whose ancestors lived in Laos. They moved to Xishuangbanna in 1944 and in 1967 settled in their village. In 2005 the community was recognized as a sub-tribe of the Hani group.

Before the founding of the People's Republic of China in 1949, people often moved across China's borders with its Southeast Asian neighbors.

According to Boben, more than 400 Paijiao people live in Laos, which is only a two hours' motorcycle ride from Mangang.

Ai Meng, deputy director of the Ethnic and Religious Affairs Bureau of Xishuangbanna, says ethnic cultures in this prefecture are under threat as more young people get a better education and migrate to cities.

"The problem is they are separated from the very soil that has nurtured their ethnicity when they go to middle or higher schools in towns and find jobs in cities, where modernity prevails," says Ai, an ethnic Blang.

Chen Ping, a researcher at the cultural center of Mengla County, has been studying the Paijiao community since 2003, and says the tribe's traditions are on the verge of extinction.

"Without prompt actions, the traditions of Paijiao will die soon," she says. "The Paijiao people's own consciousness of maintaining ethnic uniqueness is very important. Only this kind of awareness can help save their culture."

Chen, an ethnic Dai, is now working with Yao Xueqiang's wife Yila, and her father Boben, to collect the secret codes of the Paijiao people, who have no written language. The people used to weave various plants into different ciphers to express certain ideas.

"The codes once served as their written language, which I believe is the root of Paijiao culture. If they were lost one day, Paijiao culture would come to an end. Unfortunately, only a few people know these code words, so we have to be quick," Chen says.

The county performance troupe in Mengla is helping to preserve Paijiao's dancing by choreographing performances for a village dance group.

Chen plans to propose Paijiao traditions be listed as an intangible cultural heritage, but getting recognized is difficult. Heritage status would attract attention and funding for protection programs but the application process is complicated and costly and the area is poverty stricken.

Applications require a 15-to-20-minute video introduction, costing at least 1,500 yuan (US$230), plus at least 80 images for slide presentations.

Yunnan has established an intangible heritage listing system at provincial, city and county levels, and more than 70 items are listed as national heritage.

"The Paijiao people are aware their culture is dying out, but feel helpless to prevent it," says Chen. "So, I hope I can give a hand, though I'm not sure if it will work."