Yak samples are displayed during the exhibition on Tibetan yaks in Guangzhou, capital of south China's Guangdong Province, Dec. 28, 2017.(Xinhua/Liang Xu)

Visitors view exhibits during the exhibition on Tibetan yaks in Guangzhou, capital of south China's Guangdong Province, Dec. 28, 2017. (Xinhua/Liang Xu)

A girl of Tibetan ethnic group, who studies in Guangzhou, poses for photos with a picture displayed during the exhibition on Tibetan yaks in Guangzhou, capital of south China's Guangdong Province, Dec. 28, 2017. (Xinhua/Liang Xu)

Visitors view a sample of yak head displayed during the exhibition on Tibetan yaks in Guangzhou, capital of south China's Guangdong Province, Dec. 28, 2017. (Xinhua/Liang Xu)

Wu Yuchu, curator of Yak Museum in southwest China's Tibet Autonomous Region, introduces the works displayed during the exhibition on Tibetan yaks in Guangzhou, capital of south China's Guangdong Province, Dec. 28, 2017. (Xinhua/Liang Xu)

A visitor views exhibits during the exhibition on Tibetan yaks in Guangzhou, capital of south China's Guangdong Province, Dec. 28, 2017. (Xinhua/Liang Xu)