Even to the trained eye, Tuan Tuan and Yuan Yuan look identical.
The man who has seen more giant pandas than anyone else, Wei Fuwen , secretary general of the China Zoological Society, cannot tell them apart.
Professor Wei prowled the treacherous mountains of Sichuan and Shaanxi provinces for nearly three decades, tracking hundreds of wild panda families, often just by droppings or broken bamboo.
Sometimes a panda just stumbled across his path.
'Unfortunately, they all look the same; so even if a giant panda is keen enough to meet a human twice, I could not recognise it as an old friend,' he said. 'You would have to be superhuman to tell the difference between them at a glance.'
But Tuan Tuan and Yuan Yuan's keeper, Qu Chunmao , can spot the difference a mile off. The two giant pandas looked as different as they could be, Ms Qu told Xinhua yesterday.
One of the easiest ways to tell them apart, she said, was to compare heads: Tuan Tuan's is round and big, and Yuan Yuan's is small with a somewhat pointed chin.
