Dancers wearing panda costumes perform during an activity celebrating three panda cubs' first appearance at the Qinling Research Base of Giant Panda Breeding of Shaanxi Academy of Forestry in Xi'an, northwest China's Shaanxi Province, Nov. 11, 2019. Three panda cubs including a pair of twins met the public for the first time since they were born in July and August this year at Qinling Research Base of Giant Panda Breeding of Shaanxi Academy of Forestry in Xi'an on Monday. Their names were also officially announced as Qin kuer, Jia Jia and Yuan Yuan. (Xinhua/Li Yibo)

A visitor takes photos of the panda cubs during their first appearance at the Qinling Research Base of Giant Panda Breeding of Shaanxi Academy of Forestry in Xi'an, northwest China's Shaanxi Province, Nov. 11, 2019. Three panda cubs including a pair of twins met the public for the first time since they were born in July and August this year at Qinling Research Base of Giant Panda Breeding of Shaanxi Academy of Forestry in Xi'an on Monday. Their names were also officially announced as Qin kuer, Jia Jia and Yuan Yuan. (Xinhua/Li Yibo)

Three panda cubs including a pair of twins make their first appearance at the Qinling Research Base of Giant Panda Breeding of Shaanxi Academy of Forestry in Xi'an, northwest China's Shaanxi Province, Nov. 11, 2019. Three panda cubs including a pair of twins met the public for the first time since they were born in July and August this year at Qinling Research Base of Giant Panda Breeding of Shaanxi Academy of Forestry in Xi'an on Monday. Their names were also officially announced as Qin kuer, Jia Jia and Yuan Yuan. (Xinhua/Li Yibo)

A pair of twin panda cubs makes their first appearance at the Qinling Research Base of Giant Panda Breeding of Shaanxi Academy of Forestry in Xi'an, northwest China's Shaanxi Province, Nov. 11, 2019. Three panda cubs including a pair of twins met the public for the first time since they were born in July and August this year at Qinling Research Base of Giant Panda Breeding of Shaanxi Academy of Forestry in Xi'an on Monday. Their names were also officially announced as Qin kuer, Jia Jia and Yuan Yuan. (Xinhua/Li Yibo)

Three panda cubs including a pair of twins make their first appearance at the Qinling Research Base of Giant Panda Breeding of Shaanxi Academy of Forestry in Xi'an, northwest China's Shaanxi Province, Nov. 11, 2019. Three panda cubs including a pair of twins met the public for the first time since they were born in July and August this year at Qinling Research Base of Giant Panda Breeding of Shaanxi Academy of Forestry in Xi'an on Monday. Their names were also officially announced as Qin kuer, Jia Jia and Yuan Yuan. (Xinhua/Li Yibo)