Mei Lun hid in the bamboo forest, while her twin sister, Mei Huan, ignored human onlookers and ate bamboo slowly in the Chengdu Research Base of Giant Panda Breeding in Sichuan province on Tuesday morning, as they met visitors for the first time after a monthlong quarantine.

The pair of panda cubs, who returned to the base from the United States one month ago, have adapted to their new home, despite the elder sister's shyness in the face of humans, researchers said.

"Mei Lun and Mei Huan are healthy. They ate a kind of biscuit made in Zoo Atlanta and now have buns the base makes specially for pandas," Wu Kongju, a senior keeper and researcher, said at a news conference on Tuesday.